+++ #337
Subject: Marking Pens; Aviation Snips
From: Russ Erb

I've been doing some research lately with different marking
technologies.  The initial problem is that you can't use just anything
to mark aluminum.

One definite no-no is using pencil on aluminum. The carbon in the lead
will cause corrosion to start in the aluminum.

The common wisdom is to use Sharpie permanent markers. The markers with
extra fine points make nice marks on aluminum, even on shiny, smooth
Alclad sheets. If you try a water-based marker on AlClad, such as a
marker for noverhead transparencies or washable kid's markers, it is
pretty much useless. The ink does not adhere to the aluminum, but rather
beads up on the shiny surface, much as drops of water would bead
up. Removing the line is fairly easy, too. A paper towel and some
isopropyl alcohol does the job nicely, which also takes off the ink
markings from the manufacturer.

Well, that works great on shiny, smooth surfaces. But what about matte
surfaces, like the typical surface of a 6061 piece, a Scotch-Brited
piece of 2024, an alodined piece, or a primed piece?

In each of these cases, the permanent marker leaves a very nice line.
However, this line is very difficult to remove, regardless of how much
alcohol and elbow grease you use. It's as though the rag or paper towel
can't get down in the microscopic "scratches" to wipe away the ink. I
have also had cases where I thought I had fully cleaned away a marking,
alodined the part, then primed it with Poly Fiber Metal Prime. The
primer seemed to somehow reactivate what little remaining ink was there
(so little you couldn't see it) such that ink came up through the primer
and became visible again. This hasn't been a big problem so far with
internal parts and even on the outside of the flaps and ailerons, since
these parts will be fabric covered and part of the process is to apply
an opaque layer to protect the fabric from UV radiation, hence no marks
will be seen through the fabric.

But what to do for the wings and other parts where marks showing through
the finish would be very unsightly?

On a whim, I decided to try that which didn't work before. Specifically,
to try a water-based marker. I tried it on Alclad aluminum. Sure enough,
it still doesn't work. I Scotch-brited a piece of Alclad aluminum and
tried the marker--it worked acceptably. I tried a piece of alodined
aluminum--it worked acceptably. I tried a piece of primed
aluminum--again it worked acceptably. Somehow the microscopic
"scratches" allows the ink to grip the material better without beading
up, much like paint. For each case, the ink was easily and completely
removeable with water and a paper towel. The downside is that the ink
line is much less durable than the permanent ink line, meaning that
rubbing your hand or anything over the line can easily smudge it or even
erase it. If you're careful not to touch the line, though, it will work
plenty good enough.

Therefore, my recommendation for now is: 1. On shiny Alclad aluminum
(usually 2024), use the permanent marker and clean it off with isopropyl
alcohol.  2. On matte finishes, such as 6061, scotch-brited sections,
alodined pieces, and primed pieces, use the water-based (washable)
marker and clean it off with water. Be careful not to smudge away the
line.

**********************************************************************
"And now for something completely different..."

A few notes on the use of aviation snips (or "tin snips"). I'm not sure
why this doesn't appear in the typical homebuilder's books:

First, get a right hand and left hand version of OFFSET (or "Duckbill")
snips. Usually these have red and green handles. The left and right hand
refers to which direction of curve that the snips will cut, not which
hand you hold them in. The left and right hand snips are mirror images
of each other. Why each one will cut curves in only one direction is
tough to explain, but fairly obvious after using them.

Don't waste your money on the non-offset snips. The offset allows you to
cut for any distance across a sheet without excessive bending of the
sheet.  Try that with non-offset snips and the sheet will run right into
the pivot bolt. I have not found anything yet that could be done by an
non-offset snip that couldn't be done by an offset snip.

To use the snips, do not cut right to the line on the first cut. Doing
so may be very difficult and lead to distorted parts. Instead, rough cut
to within about 1/8" of the desired line. Then go back and finish cut to
the desired line. Doing this will let the thin piece of scrap bend out
of the way while leaving the part undistorted. Additionally, the scrap
doesn't get in the way of cutting curves.

Be prepared to swap back and forth between the left and right handed
snips as required. In general, use the one that works for the current
cut. If it's not working, try the other one.

At least one of the jaws of the snips typically will have small
serrations on it. Presumably these serrations keep the snips from
slipping while cutting. Unfortunately, these serrations will leave marks
on the parts.  You'll want to scotch-brite these marks out to remove the
stress concentrations, just like you would for any other scratch. I have
not tried grinding the serrations off of the snips to see what effect it
would have.

+++ #338
Subject: Re: Marking Pens; Aviation Snips
From: Bruce A. Frank

I lay out and weld aluminum projects every day. Most finished projects
are anodized, powder coated, or alodyned and spray painted. We use the
really fine point Sharpie permanent markers to layout and the heavier
markers to show part numbers and other information. Before the parts go
to the final finish every thing is wiped down with acetone. Acetone
removes all traces of the marker and there are no show or bleed throughs
of the final finish. The most stubborn thing to remove is the glue from
the strapping tape used by the shipper. This is best removed with
mineral sprits followed by acetone.

I have never heard of the carbon in a pencil causing corrosion of
aluminum.  Maybe something in the binder? What is your source of
information about this problem? I have sooted pieces of aluminum in my
shop, cut from pieces that were going to be annealed, that have been
hanging there for years. No evidence of corrosion.

I have stacks of sheet material (2024,6061, & 5053) with the alloy
marked in pencil and I have seen no sign of corrosion. The pencil line
can be buffed off with a cloth or wiped off with acetone.

+++ #340
Subject: Re: Marking Pens; Aviation Snips
From: bearhwk27-

1. For marking on "stuff" search out and try a "Grease" pencil. Good art
supply store will have them. Just sharpen with a pencil sharpener.  Will
wipe off with rag or several solvents.  To make a mark last for a long
time reference mark just cover it with a small piece of clear tape
"Scotch"tape.

2. If you take the serration's off your snips they will not cut and
track as well and you will wish you had not modified them.

+++ #341
Subject: Re: Marking Pens, Pencils are a no no.
From: bearhwk27-

With respect to pencils... I guess that the most recent relearn of this
issue was with the cracks in the C5A wing. Many of the stress cracks
propagated from areas that had pencil marking. The culprit is the
graphite in the pencil lead reacting with moisture.  You will not see
the problem with your naked eye and the application of load to a piece
accelerates the action.

+++ #344
Subject: Re: Marking Pens, Pencils are a no no.
From: Todd Chisum

For parts where you don't want to leave marks, try laying a strip of
Scotch tape (like in your desk top tape holder), then marking on the
tape with a pencil, pen or ??. After you cut, you can peel the tape
off. Scotch makes a version of this tape that peels off very easy with
no residue left behind.

Does the ink in the Sharpie pens cause corrosion if not removed?

+++ #345
Subject: Re: markers
From: Rodney Smith

While on the subject of markers, I have read a couple of places that a
silver pencil is good for marking steel. I bought a couple and found
that the marks were hard to see and very easy to remove just by smudging
with your thumb. Get a little cutting oil on the mark and it disappears
immeadiately. I therefore have been using sharpie markers for marking
steel parts and that has worked out a lot better. The sharpie ink is a
little more resistant to the cutting oil also. For what it is worth I
have seen the same warning about using pencils on aluminum more than
once in print.  Also to further confuse things, at our plant it is a
definite no-no to mark stainless steel piping with ink markers. The ink
supposedly corrodes the stainless steel over time.

+++ #355
Subject: Re: Results: Ink removal experiment
From: Bruce A. Frank

I understand your reluctance to expose yourself to solvents, but
acetone's impact on the body is little different than alcohol. It is one
of those substances that our body makes a little bit of, so it is in our
systems in trace quantities. That being said, one can still become
sensitized to it and react to it with headaches and upset stomachs. It
is a pretty good general cleaning solvent with few of the really bad
side effects of such as Toluol or MEK.

+++ #513
Subject: EAA Chapter 1000 Standard Work Tables
From: Rod Smith

The last few weeks of my time off I have been busy building work
tables. Up to now I have been doing all my building at my work
location. Now I will be starting to build the wings at home so I will be
attacking this project on two fronts so to speak. I have a large garage
but I needed to get it organized and some work tables built. I have
built four tables pretty much to plans as found at :
http://www.eaa1000.av.org/technicl/worktabl/worktabl.htm. These are a
very well designed, very sturdy table 2 x 5' in dimension. You can bolt
them together to make larger tables as necessary. I built one of them 4'
wide. I will mount a roll of aluminum on the end of this and do my
layout and cutting for ribs on this table.  It will be away from the
wall for access to both sides. The other three tables are laid out in a
L around one corner of my garage. I will mount my drill press between
the two on one wall and this will provide a large enough area to
fabricate the wing spars. My hat goes off to Russ and the rest of the
Chapter 1000 gang. Check it out.
 
+++ #519
Subject: Screw Levelers
From: Russ Erb

I didn't bother with levelers, partially because I didn't want to
bother, and partially because it forces all of the load through such a
small area (I like the whole leg resting on the support).  My garage
floor is far from level, so this is an issue.  I just shim up the
appropriate legs with pieces of plywood and aluminum shims (the waste
from lightening holes works well).

+++ #529
Subject: Re: EAA Chapter 1000 Standard Work Tables
From: Todd Chisum

>Do you or others use the screw levelers for the legs and if so where do
>you source them.

You can get what is called "elevator bolts" to level tables with. They
should be available at any fastener supplier, maybe not a hardware store
though. Something I have used on work tables is to drill a hole in the
bottom end of the leg, insert a 5/16-20(?) Tee nut and use a 5/16-20
carriage bolt for a level adjustment, if you can find 3/8 or 1/2 tee
nuts and carriage bolts that would be even better. You will also need
the Tee nuts for the elevator bolts. The elevator bolts have a large,
flat head and a grip area like a carriage bolt for
adjustment. McMaster-Carr also sells the elevator bolts.

+++ #531
Subject: 2nd airplane
From: gdanfor-

In building the Hatz, I found a sand blaster most handy and you can
build your own easily.  Best source for parts is "TIPTOOLS.com".  They
have plans and every thing you need to build a very inexpensive blaster.

+++ #602
Subject: Re: Interested builder
From: Float-by Shooter

> and while not a pro I can get two pieces to stick together. By the way
> are you guys using the tubing notchers, I've seen these tools
> advertised and wondered if they work?

My impression is that most of us here on the list have not yet reached
the point where a tubing notcher would be practical (ie the fuselage).
I've read various opinions on them in the course of my research, and
most people seem to either love them or hate them.  I know that on this
forum we have at least one of each and you will probably get both of
their opinions.

My EAA "Aircraft Welding" book shows what has to be the slickest way to
notch tubing, use a lathe with a large reamer chucked in it, and a
fixture to hold the tubing steady as you feed it into the reamer.  Of
course the problem for most of us is no lathe...

+++ #604
Subject: Re: Interested builder
From: budd davisson

Re: Tubing notchers

Everyone has their own style of putting tubing together and y ou'll
develop yours. Don't get so caught up with gadgetry, however, that it
slows the project. You may find you spend more time setting up a tubing
cutter (if you're talking about the kind that is a hole-saw in a drill
press) to get the angle just right than it is worth. Another problem is
you have to have the length measurement exactly right. By grinding, you
can start a little long and gradually shorten it to get exact fits.

A tried and true method is to dress the edge of a grinding wheel to the
diameter of the tubing being joined. that works really well and is fast.
Some of us just leave the edges of the wheel square and use the edge to
"wipe" the radius in. That happens in nothing flat. I once started
timing how fast I did different operations and found I could fit a
vertical in 14 minutes and a diagonal in 18. Guys that really know what
they are doing are probably much faster. Knowing those times, I could
duck out while waiting for dinner and get something accomplished.

A quick hint: don't mount your grinder on the bench. Make a movable base
for it (I use an old kitchen base cabinet that's only a foot wide and
put wheels on the back edge), so you can always have it right at your
elbow where you're working. Otherwise you waste too much time walking
back and forth to the grinder.

The beauty of gas welding is the bead is always so much wider than the
thickness of the metal that it bridges and melts irregular edges really
well. Although smooth pretty edges are nice, they aren't necessary so
long as the gaps don't get ridiculous and the weld puddle has good
penetration. Just the reverse is true on fittings however. There, the
prettier, the smoother the edges the better.

+++ #606
Subject: New member
From: Mike Guthrie

I have been reading your postings since coming from Bob's builbers
diner, talk about being reinspired. Back in the shop for the winter. A
coment on tube notching you can get small sanding drums for your die
grinder that fit the size of the tube your fitting, I tryed these for
practice welding with good results. The ligihtng holes in the spars are
they flanged?

+++ #611
Subject: Tube Notchers
From: Tim
 
Went down to the basement and grabbed mine, for a closer look. Dean/me
purchased two from Harbour Freight Tools, last July while on Sale. Think
they were was $35.00ea...yeah, thats why we bought one each....This
notcher is probably a copyright rip-off/spin-off of the 'Ole Joint
Jigger' or one of those notchers you see in the back of Sport
Aviation. But the difference being, this knockoff is made in
CHINA....Bottom Line is surprising...High Quality with a very good
finish for CH-CH- China.....I avoid tools from there, Canada does big
trade with the Commies and we see a lot of Shizen coming out of
there...kinda like the early 60's and JA-PAN......How does it Work??????
Haven't a bloody clue, as I have yet to call Charlie at Dillsburg
Aeroplane Works for 4130 tube. This coming summer I plan to tackle my
fuselage....Wouldn't wanna shock cool those cluster welds with a cool
Canadian Winter ;-)
 
+++# 627
Subject: Tubing Notchers and other metal working tools
From: Russ Erb

Okay, I'm finally ready to weigh in on this one.

>Everyone has their own style of putting tubing together and y ou'll
>develop yours. Don't get so caught up with gadgetry, however, that it
>slows the project.

I understand what Budd was saying here, but I feel compelled to say that
there are times that "gadgetry" is a good thing.  I'm currently
assembling my first wing, after completing the flaps and ailerons.  Some
of you may have thought me over-doing it when I built very precise jigs
to route out all of the ribs to their precise sizes.  Sure, it took
extra time to make the tooling, but I could also claim that I was able
to cut out the rib blanks faster than I would have one at a time with
tin snips.  Definitely more accurately and precisely.

The payoff has been that the fit up of the ribs has been incredibly
easy.  Almost plop it up there, and it's in the right position.  Kind of
like the old Fram commercial--you can spend the time now, or you can
spend it later.  There are times that good tooling is worth the effort.

As a friend of mine says, "The reason we build airplanes is so that we
have a reason to buy all sorts of cool tools!"

Reference the horizontal/vertical bandsaw: >You'll never use it as a
horizontal cut-off saw because it is unnecessary.<

I heartily and respectfully disagree!  I've used it this was as much or
more than I've used it vertically.  This is my favorite mode, in fact.
You clamp in the tube (or whatever) in place, turn the saw on, and walk
away.  This is the part I like--when it's done, it automatically turns
itself off!

My preference is, when possible, let the technology make the cut
accurate rather than the art of handling the piece.

As for the tubing notcher, I have one of the Harbor Freight versions.
I've used it some, but not much because it only works down to diameters
of about 3/4", and most parts on the wing steel are smaller than that.
For those, I used the grinding wheel to shape the parts.

Following is an article which I have written for the Bearhawk Reference
CD (available sometime hopefully in 2000) and the EAA Chapter 1000
newsletter.  It contains my experiences and opinions on several
metalworking tools.  The pictures aren't included in this e-mail.

***********************************************************************

Notes on Steel Working Tools

It probably comes as no surprise to you that having the proper tools for
a job makes the job much easier. Perhaps this is why we tend to
accumulate tools so quickly. I haven't checked lately, but I wouldn't be
surprised if my tool expenditures are still ahead of my material
expenditures.

Growing up, I was exposed to two primary building materials: wood and
steel. I found wood very easy to work with, but steel was very difficult
and I came to avoid it whenever possible. Looking back, I can see that
the primary reason I didn't like working with steel was that my Dad's
shop was not well equipped with tools for that purpose (while it was
equipped for wood working). I seem to remember having a hack saw, tin
snips, and a file or two. Not exactly what you would want to start
building an airplane with, unless you have an unnatural aversion to
power tools.

So naturally this childhood aversion would drive me to build an airplane
with a steel tube fuselage and tail, right? Actually it was more of a
case of ignoring those childhood memories and figuring that a few good
power tools would help.

Sure enough, with a better set of tools, steel was significantly easier
to work with. The tools that I use most for steel are a
horizontal/vertical metal cutting bandsaw, a 1 inch belt sander, a
grinder (same one that has the Scotch Brite wheel for aluminum on the
other side), a Moto-Tool with a 1/2" grinding wheel and a fiberglass
cut-off wheel, a 3" metal shear, a tubing notcher, and the usual
assortment of drills and files. Of course there's some sort of welding
equipment for putting together the stuff you've cut apart, but I'll save
that discussion for a different article.

Horizontal/Vertical Metal Cutting Bandsaw

Harbor Freight 
http://www.harborfreight.com/ 
Item 37151 $179.99 

This bandsaw uses 1/2" x 64-1/2" blades, which are available with either
10 teeth per inch (tpi) or 18 tpi. For aluminum bar stock, I've found
that the 10 tpi blade works best. Using an 18 tpi blade results in the
aluminum shavings sticking in the teeth and thus clogging up the blade
to the point that it doesn't cut anymore. With the 10 tpi blade, the
shavings fall out properly.  For steel, I normally use the 18 tpi blade
for steel.

By adjusting a belt on pulleys, the saw can be run at three different
speeds. Guidance is given on selecting speeds, but typically I just run
it on the slowest speed with adequate results.

In the vertical position, it can be used like a conventional bandsaw,
feeding the stock through by hand. This is the best position for
"ripping." Cuts can be made to any length for a width on the inside up
to 2-3/4 inches wide. Because of the 1/2" width of the blade, cuts are
mostly limited to straight cuts. When using the saw in the vertical
position, the best way to keep the saw from falling over or scooting
across the floor is to sit on the base portion like you would sit on a
horse. The only odd thing about this, other than making sure the vise is
out of the way, is that it puts the power switch under your "hinders."

For "cross cutting," it is far more convenient to use the saw in the
horizontal position. In this case, you secure the workpiece in the vise,
lower the saw blade onto it, turn the power on, and walk away to do
something else. The cool part of this design is that it will work away
at sawing through the piece, feeding itself by gravity, then shut itself
off when it is done!


To use the saw in the vertical mode, a work table is provided. However,
this table must be removed to use the saw in the horizontal position
because of interference. It has been shown that the table can be cut
down in such a way that there is no interference, yet still be useable
in the vertical position.

1" Belt Sander

I use a 1"x30" belt sander from Sears. It gives you about 4-1/2 inches
of working space. There are also 1"x42" belt sanders (shown here)
available. I found out about the bigger size after I had bought mine,
but I have not been constrained significantly by the shorter working
area.

My belt sander has a 5 inch disk sander on the other end of the motor,
which I have pretty much never used. I don't care much for disk sanders
because they remove material unevenly. This is mostly because the
tangential velocity of the sanding medium increases as you get further
from the center. (If you have an application where a disk sander is
better than a belt sander, I'd love to hear it!)

I first thought it would be more useful to have a wider belt, such as a
3" or 4" belt like woodworkers use. Even so, I bought the 1" wide belt
sander because 1) it's what "everybody" said to use, and 2) it was less
expensive. As it turns out, it has been quite satisfactory for virtually
everything I've needed to do. I think the difference comes from where
wood is typically "wide" (3/4" or greater), steel is typically "thin"
(under 1/8"). For doing edges and convex curves, the 1" belt is plenty
wide. On the rare occasion that I need something wider or close into an
acute corner, I clamp my handheld 3" wide belt sander upside down on the
work table.

The belts are available at Harbor Freight in 80 grit and 120 grit. Buy
them in the 5 pack package, which is dirt cheap compared to buying them
individually at Sears. I have found these belts to be of good quality,
and they last significantly longer than I would have expected.

I recommend that you use different belts for sanding steel and
aluminum. That way you won't get little bits of aluminum embedded in
your steel or, worse yet, little bits of steel embedded in your
aluminum. Dissimilar metal corrosion, you know. Same reason you don't
use steel wool on aluminum.

Grinder

I use a basic bench grinder, again from Sears. I decided on the 6"
grinder after long and exhaustive research (specifically, I opened the
Avery catalog and determined that their Scotch Brite wheels are 6" in
diameter).

Grinders are similar to table saws, in that they come with guards that
people tend to take off and not use.  Now I'm all for safety, but there
are times when safety devices get in the way and make the job less safe,
or prevent the job from getting done.

I bring this up because I use the guard over the grinding wheel but not
over the Scotch Brite wheel. This was for two reasons.  First,some of
the aluminum parts I used the Scotch Brite wheel on are long enough that
the guard would be in the way. Second, a Scotch Brite wheel is typically
used differently than a grinding wheel. The workpiece is placed on the
part of the grinding wheel that is turning toward you, whereas the
workpiece is placed on the part of the Scotch Brite wheel that is
turning away from you.  Since the guard is designed for grinding wheel
use, it would cover the part of the Scotch Brite wheel that you need to
use.

My guard came with a yellow plastic piece that holds a light bulb and
supposedly serves as eye protection. Because of its color, I find it
makes the part more difficult to see. I usually just move it out of the
way and use goggles or safety glasses.

Moto-Tool

Another extremely useful tool is a Dremel Moto-Tool or one of the many
look-a-likes. Of course, this tool does just about everything but
hammer, but there are two uses that I am inerested in for this
discussion. With a 1/2" grinding wheel, this tool is useful for grinding
all of those inside curves that none of these other tools (except some
files) can get to.

The other use is with the fiberglass cutting wheel. This will cut in
many areas that no other tool will get to. Be sure to get the cutting
wheel made of fiberglass. The emory cutting wheels may be cheaper, but
they have a MTBF on the order of seconds.

3" Bench
Metal Shear

Harbor Freight 
http://www.harborfreight.com/ 
Item 32153 $49.99 

You may have seen a 4 foot or larger shear, which is very nice for
cutting thin sheets of aluminum in one motion. The drawback of these
shears is that they don't have sufficient capacity for steel in
thicknesses larger than about 0.032.

Enter the 3 inch bench metal shear. While the 4 foot shear cuts like a
paper cutter, the 3 inch shear cuts more like a pair of scissors. Don't
be fooled by the 3 inch dimension--the body of the shear is slotted such
that straight cuts of any length can be made. It is also useful for
trimming convex curves down to about 3/4 inch diameter.

The shear capacity is quoted as 12 gauge steel, which is a thickness of
0.1072 inch. I have demonstrated its capability to cut 0.100 4130
steel. Mike Meador has cut up to 0.125 4130 steel, but says you don't
want to feed it a steady diet of such thick material.

An adjustable stop keeps the stock from twisting between the cutters,
which is required to allow the cutters to do their job. This stop is a
little less than 3/4 inch from the cutter, which means that the material
on this side of the cut line has to be 3/4 inch wide or greater for the
shear to work.

The handle for the shear is not permanantly attached, but rather fits on
a hex head like a box end wrench. You could conceivably use a wrench or
socket instead, but the supplied handle seems sufficient for as thick of
material as the cutters can handle. I did find that the handle tends to
work itself off of the hex head with continued use--this could be quite
a surprise if it came off while cutting! The simple solution is to
remember to push it back on before each cut.

Rather than mount the shear directly to a work bench, I mounted it on a
2 foot 2x4 with counterbored carriage bolts. This 2x4 was then set
across the short dimension of a EAA Chapter 1000 standard work table and
held on with bar clamps.

For cutting the thicker pieces, the best technique I found was to hold
the handle with my arm fully extended, step up on lower shelf, and then
lean back, thus using gravity to supply the force to cut instead of
muscles.

When making a cut longer than 3 inches, it is critical to remember what
you learned in kindergarten about using scissors. That is, don't cut all
the way to the end of the blade. Stop before the end of the cutter gets
to the sheet and reposition the sheet. If you don't, the sheet will be
distorted as the cutter continues to shear but the sheet immediately
past the end of the blade is not sheared. Try it with scissors and paper
(no rocks required) and you will see the same result.

(It appears Harbor Freight may have discontinued this item. However,
they still carry other similar items.)

Tubing Notcher

This is the doofus that holds your tubing at a particular angle and then
uses a hole saw to cut the fishmouth end for a "perfect" fit. The most
advertised version of these is the Ol' Joint Jigger
(http://www.jointjigger.com/, $165). Their ad will lead you to believe
that any other tubing notcher is inferior. This may be true, but it
doesn't mean the others are inadequate.  I use one from Harbor Freight
(Central Machinery, Harbor Freight Item 35782, $60) which cost
significantly less. I've used it several times and haven't had any
trouble.

Don't try to save even more money by just using a hole saw from the
hardware store mounted on a 1/4" bit--it won't work (I tried it). Since
the hole saw is cutting the tube without the stabilizing presence of the
center drill bit, the mandrel requires a lot of stability against side
forces. The tubing notcher uses a long, heavy bearing shaft to provide
this stability. This shaft slides in plain bearings, and should be oiled
during use and kept clean from dust and shavings.

The tubing notcher uses bimetal hole saws that are available at many
sources, including your local Home Base or Home Depot. These hole saws
screw on the mandrel with either 1/2 inch or 5/8 inch threads. The
tubing clamp can hold tubes up to 2 inches in diameter. I was able to
get hole saws at Home Base in diameters from 3/4 inch to 1-1/2 inches,
and have seen hole saws available up to 2 inches in diameter. The
minimum practical length of tubing that can be notched is around 4 to 5
inches because of the location of the tubing clamp.

When cutting, be sure to use plenty of cutting oil. Don't try to use
motor oil--it doesn't have the same properties. A good cutting oil is
available from Avery (Rapid Tap Cutting Fluid, 4 oz., #7016, $3.50). Be
sure to feed the saw slowly and lightly into the part. The tooth on the
hole saw is generally excessively large compared to the thickness of the
tubing. As such, if it is fed too fast and with too much pressure, the
tooth can be forced to take too large of bite which will result in
breaking the tooth.

Drill Bits

A discussion of drill bits could fill a book. In short, I recommend
using cobalt bits with 135 degree split points for drilling aluminum and
especially steel. High speed steel bits dull too quickly. The 135 degree
split points reduce "walking" by the drill when starting a hole. Using
cutting oil also speeds the drilling process and helps the bits last
longer.

Cobalt drill bits are available in number sizes and fractional sizes
from Avery. Home Base also has cobalt drills in some fractional sizes.

I am told that titanium nitride drill bits are even better than cobalt
drills. I have not tried any, so I can't say. I have seen titanium
nitride drill bits in fractional sizes available at Home Base.

Files

Some operations still have to be done by hand, and for that you'll need
a set of files. I'd recommend that you have at least one "normal" size
mill bastard (yes, that's what it's called) file, available at your
local hardware store, and a set of specialty files like Avery's Swiss
Pattern Needle File set (12 pieces, #475, $22, or 6 pieces, #476,
$11.50).

In Summary...

I have since found that if you have some appropriate tools, steel not
that difficult to work with. In fact, the belt sander and grinder look
pretty cool when making a big shower of sparks--you feel like you are
really doing something.  However, you'll want a good pair of leather
gloves as the parts do get hot!

+++ #674
Subject: Flute plier results
From: Jenni Thatch

I have composed up in my mind that a taper pin (i.e cone shaped) would
work even better than a cylindrical pin.  I have at my disposition the
equipment to make such a tool but I am curious about your results using
the ones Bob has in Beartracks?  This topic has probably been taken up
before so if you know where I can research it I would appreciate your
input.  Thanks in advance!!
 
+++ #675
Subject: Re: Flute plier
From: csisters-

in response to your inquiry about the fluting pliers the ones in the
news letter work excellent. Except for the end of the nose ribs it takes
very little fluting to straighting the ribs.Dont try to reinvent the
wheel JUST FLUTE IT.

+++ #681
Subject: Re: Flute plier
From: Gary Danford

Flute Pliers made from a pair of Vice Grips work excellent and you can
easily adjust the amount of pressure.  I bought mine from Aircraft Tool
but i'm sure you can make a set easily.

+++ #684
Subject: Re: Flute plier results
From: bearhwk27-

The fluting pliers sold by Aircraft Tools utilizing vise grip handles
are great ! More leverage = easy to use. Adjustable crimp pressure= fast
consistent crimp. If you try to do a conical tool the vise grip pliers
will be mandatory, it takes a lot of force to do a conical flute.

+++ #685
Subject: Re: Flute plier results
From: Float-by Shooter

> The fluting pliers sold by Aircraft Tools utilizing vise grip handles
> are great ! More leverage = easy to use. Adjustable crimp pressure=
> fast consistent crimp. If you try to do a conical tool the vise grip
> pliers will be mandatory, it takes a lot of force to do a conical
> flute.

Since everybody is plugging their favorite fluting pliers, I bought one
from Avery Tools which makes very narrow, good looking flutes.  It is a
non vise grip type, but it has extra long handles to give the required
leverage.

+++ #686
Subject: Re: Flute plier results
From: Bill Cox

I have several pairs of homemade fluting pliers similar to those shown
in the newsletter that have served me well for the past 30 years.  A
couple of years ago I saw the ones that Avery sells and bought a
pair. They make the best flutes of any I've used including the ones made
from vise grips. I started out with the visegrip type in the early
sixties and only used them for a few months until I was shown the
homemade ones similar to the newsletter.

+++ #793
Subject: metal shear
From: Float-by Shooter

I just thought I would share some information with y'all about a metal
shear that I bought, which I don't remember having mentioned before.

I bought it to help with the bodywork project I am currently mired in,
for trimming patch panels and reinforcements.  I needed a shear because
my air shears broke and I was interested in getting a bench shear.  I
wanted to get a nice beverly shear but the cost was too much to justify,
which I am now thankful for.

Instead I bought a rolling shear which is made by Sykes-Pickevant and
isn't nearly as bulky or heavy as the Beverly (though probably not as
powerful).  It has 2 rolling blades, one of which is operated by a
simple racheting mechanism, and has small serrations which grip the
metal and pull it through the shears.  The serrations don't seem to mess
up the edge any worse than my tin snips so they should clean up well
with a scotchbrite wheel.

Last week I used it to shear a couple of 6-7 foot lengths of .040
2024t-3 to repair a delivery truck box (not the ideal alloy, but it was
there and we didn't really need it for anything else) and it worked
perfectly with another person helping me feed it through.  So far I've
only used it on straight cuts but it can handle gentle curves, which may
be of use to those of you still working on ribs.  I'm going to use it
when I get around to cutting out my spar webs, but I don't plan on
putting any 4130 through it.

I bought mine from the eastwood company for 89.99, part number 28034.
http://www.eastwoodco.com/

No relationship except as a satisfied customer.

+++ #1135
Subject: Re: Tex-Montana Express
From: Float-By Shooter

> them but It was what I could find and afford at the time. I have a
> five hourse direct drive air compressor. I have a pneumatic jitterbug
> sander and pneumatic sander and paint gun from body work days. I have

You are extremely fortunate to have an air compressor. I don't think the
sanders will be of much use to you but you will eventually need the
paint gun.

> The tools on my list would be a gas welder, metal brake, and??? 

What kind of metal brake did you have in mind? Any good quality bending
brake is expensive (new), and an 8 footer capable of bending the spar
webs is totally out of the price range of most builders. Some of us have
managed to fabricate our own bending tools for some of the smaller parts
(check the FAQ), but that only goes so far. I think that a good 4 foot
brake would be great for a lot of the other stuff like the .032 4130,
fuel tanks, etc, but then you run into the same problem again, cost. A
new US made 4 foot pan and box brake (16 ga. capacity) runs around $1200
new. I might be able to scrape together enough (I will use it enough on
other projects that it would be worthwhile), but unless I can find a
good deal on a used one I will probably end up making my own. I have a
book which gives instructions for making a 5 foot straight brake
supposedly of 12 guage capacity, but you would need access to an arc
welder of some kind to build it.

> Do you attach the scotch-brite wheels to a bench grinder? 

That is what most people do. I have mine on a purpose built buffing
motor which gives better access around the wheel, but it was something I
already had and wouldn't have bought strictly for the scotchbrite wheel.

> What tools are needed for the riviting? 

Either a rivet gun or a squeezer. The squeezer is quieter and probably
easier to use, but very limited in what you can reach with it. The rivet
gun will do just about everything but takes more practice to get it
right.  If you can only afford one, get the rivet gun, in the 3X size.

> I am guessing that you use a band saw to cut
> up the metal?

A bandsaw is great for the 4130 steel and the thicker aluminum
parts. You will need something else for the thin aluminum sheet. What
you use to cut your ribs and spars is more a matter of personal
preference, some have used routers and special templates, while a lot of
us (including myself) have been perfectly happy with offset tin
snips. One thing which would definitely make your life easier is a small
air shears (since you have a compressor already), use it to rough out
your rib blanks from the sheets, and finish trim with your snips or
router.

Other air tools which can be had reasonably that might help are a cut
off tool and die grinder, but you won't need those until you start
working with 4130.

+++ #1175
Subject: router for aluminum
From: Alan Nauman

I have a 2 hp Ryobi router. I have it mounted in a custom router
table. What type or bits do you use to trim or cut the aluminum parts
with a router? I always thought it would only work on wood.

+++ #1179
Subject: re router for alum
From: stephan pelgar

there are bits made for cutting alum with a router.there like a end mill
with a slight taper and a quick cut flute.i know that ats(aircraft tool
and supply) company sells them.i think there like 10 bucks a piece.as
for regular bits im not really sure if they will work.hope this helps

+++ #1181
Subject: Re: router for aluminum
From: Float-By Shooter

> I have a 2 hp Ryobi router. I have it mounted in a custom router
> table. What type or bits do you use to trim or cut the aluminum parts
> with a router? I always thought it would only work on wood.

When I tried it, I used a laminate trim bit (the kind with a ball
bearing on the bottom) and a template cut to the size of the rib
blank. It worked OK, but was extremely noisy and threw little bits of
aluminum all over the place. Might not be a problem for you, but my work
area is such that cleaning them all up was extremely difficult. Russ' CD
has some good pictures of templates for this method.

+++ #1183
Subject: Re: router for aluminum(YES!)
From: Bruce A. Frank

Wood bits work as well or better on aluminum. I spray my bits with a
little WD-40 to help prevent the aluminum from sticking as it will
sometimes (you can carefully pop it off with a screw driver). Also the
wax that you use on saw blades will help the chips clear from the router
bit more easily. The table saw does an excellent job of cutting
aluminum.

In the metal shop where I work part time (needed access to the tools I
don't have yet to build my plane)all of our sheet aluminum, over about
1/16th inch, is cut on the table saw. All of the aluminum we cut to
shape, like ovals and circles and stencils is rough shaped with the
plasma torch the brought to final spec with a router using regular wood
bits. Carbide bits hold their edge longer but that's important only if
you are cutting aluminum day after day.

+++ #1192
Subject: Re: router for aluminum
From: Tom Kennedy

Try a one piece solid carbide bit used to flush trim laminates.  These
do not have a bearing and will come in two basic versions- one will give
you a flush 90* trim the other has a 7* bevel towards the top.  Either
one of these bits will take out less material that a flush laminate trim
bit with a bearing guide would.  The 7* bevel would be my choice because
it takes out even less material than the 90* bit. With a template there
is no need for a table to rough cut your rib blanks.  Might be able to
use the table as a mill to insure uniform flange width after forming
rib.
 
Both bits go for about 5-6 dollars a piece at:
http://www.grizzlyimports.com/products/index.html
 
 
PS I took back my 2 HP Craftsman (Ryobi) router to Sears for a refund
last Sunday.  The shaft lock was always jamming and the locale repair
shop said this was a common problem.  Got me a 2 HP Bosch!
 
+++ #1193
Subject: Re: router for aluminum
From: bearhwk27-

I have routed everything using a standard 4 flute Titianium coated
carbide end mill.  These are available from most machine tool supply
houses at about $ 11.00 a crack. I have only used 1 for the project this
far. The coating on the cutter keeps from loading up the 2024 material.

+++ #1197
Subject: Re: router for aluminum
From: george velguth

A few questions about your aluminum routing experience:

1. When you say you routed "everything" do you mean all aluminum parts,
or ribs only?

2. How close did you route to finished size, and how did you clean
up/trim to finished size after routing.

3. Did you find it best to overcut or undercut while routing aluminum?

+++ #1212
Subject: Re: router for aluminum
From: bearhwk27-

I routed everything to size and finished dimension. Router templates
were made out of 1/2 thick high density particle board that had the
exact contour needed. The aluminum to be cut was sandwiched between the
template on top and a backer board below. Dowel pins located and
retained the templates and aluminum.  The end mill cutter has a smooth
shank that followed the contour of the template. Parafin wax was rubbed
on the template and aluminum surface for lubrication.  Very little
cleanup of the cut was required and most were burr free.  Final
detailing was via 320 sandpaper.  Ribs,Spar webs,Capstrips, Fueltanks
have been routed.

Hooked the router up to my shop vac and kept the chips to a minimum.
Fast, accurate, noisy.  I would not use a standard router bit or
laminate bit. To rough and coarse.

+++ #1214
Subject: Re: router for aluminum
From: Russ Erb

> I would not use a standard router bit or laminate bit. To rough and
> coarse.

To express an alternate opinion--I used the carbide bearinged laminate
bit. I thought the resulting edges were sufficiently smooth, especially
compared with everything else I could have used. They weren't perfectly
smooth, but were ready to go straight to the scotch brite wheel, which
smoothed everything up just fine.

I like the idea of a bearing rolling on the pattern better than a
spinning shank--no wax required--but that's my opinion. I think either
method will do just fine.

+++ #1217
Subject: Re: Tex-Montana Express
From: pfflyer-

Concerning, the Racers Guide to Fabricating Shop Equipment, I bought one
from Amazon a couple of weeks ago. Don't remember the price, but it
arrived within a few days.  There are well written plans for a hydraulic
press, engine stand, rotiserie (for welding up the fuselage), cherry
picker and automated cutting torch.  Already built my own hydraulic
press but not sure if I want to spend the time building the brake.  Have
access to an 8' brake, but it is challenged trying to bend the 1/8
flange on the 4130 channels.  If I knew it would do a good job on those
pieces, I would build it, but then I wouldn't have access to the other
fellows shear. Nothing is ever simple.

+++ #1228
Subject: Re: router for aluminum(YES!)
From: Stephen Wolfe

Don't know about routing aluminum yet, but I did find a great lubricant.
It's called "B'LASTER", and is available at auto stores and Meijer's.
Has all sorts of estoric claims on the label, and so far, all of them I
tried have worked.  Good for cleaning your guns, also.  ( In case you
want to take a liberal to the range to show him what he's been missing)

+++ #1267
Subject: Router cutters
From: bearhwk27-

In retrospect the main difference between routing with an end mill or a
laminate router may be the actual router itself.  Differences in spindle
speed ( cutter velocity ) and torque are probably a large part of the
equation. So if one is not working...... try the other.

+++ #1430
Subject: Re: Form Blocks by the pound
From: Alan Nauman

I followed the Router Workshop for a long time and that is the method I
used to build my router table also. I looked for the mounting plates but
they were like $30 for a little peice of plastic so I made my own out of
a piece of plexiglass. I set the plate into a sheet of laminated
particle board that is about 2'x4'. I usually just clamp the table down
to a couple of saw horses for a stand. That way I can set the router on
a shelf and put the table against the wall when not in use and it takes
up very little space.

I was going to use a similar method for the form block but I was not
going to use aluminum for the pattern. I have not decided what to use of
the patern but some cheaper wood. I bumped into a sheet of stuff at Home
Depot that I will probably use for the form block. It is 3/4 or 1"
masonite. It has all sides finished and it weights a ton. It didn't have
a price so I don't know the cost but ut had a label and it was called
SUR something. I have never seen or hears of this size and finish of
compressed wood product but it looks like it is just what the
Dr. ordered.

Looking forward to receiving my plans.

+++ #1435
Subject: routers
From: Ernie Romito

I have used a router for building many pieces of furniture. I would feel
more comefortable using a router following a pattern rather than using a
fly cuter. There is a catalog that has hundreds of router bits. They are
usually carbide tipped. It is Eagle America. There bits that have
bearings either on the top or the bottom. Just be careful to keep the
aluminum chips away from your eyes. A router can be capable of making
precise cuts but be really careful.  My machines turn more than
24,000RPM.

+++ #1532
Subject: Re: Ceremonial Removal of the Tags
From: Russ Erb

> Russ, what did you use to stamp the dog tags with the numbers?

I bought a stamping set from Harbor Freight (Item 00800). These are
little pieces of steel with the letter or number on one end, just like
moveable type. Whack it on the end with a hammer to stamp the character.

$8.99 on the Harbor Freight web site.

+++#1533
Subject: Re: Ceremonial Removal of the Tags
From: Alan Nauman

I just picked up the adds at the locak store and the same stamp set is
on sale for 4.49.

+++ #1741
From: Schutt, Barry C  <Barry.Schutt@P...> 
Subject: [Bearhawk] Re: Scotchbrite 

> For all you folks who have completed your wings...
> 
> What are your recommendations for purchasing Scotchbrite pads
> and wheels?  In other words, what worked best for you?  In Mike's
> rib book you can see a photo of Bob with a wheel in his drill
> press.  I'm wondering what colors and sizes worked best.  I'm
> leaning toward 2" purple, and maybe rose pads.  Any thoughts?
> There's a lot of 100 tan pads on eBay, but I think tan would be
> WAY to coarse.

I've found that I use some fine, some medium(rose) and some coarse(tan),
but mostly fine(blue)---get some of each and try them out.

+++ #1742
From: Russ Erb  <erbman@c...> 
Subject: [Bearhawk] Scotchbrite 

> For all you folks who have completed your wings...

I haven't "completed" my wings but feel qualified to answer. I use the
Maroon pads. Works good, and the aluminum oxide grit is corrosion
friendly to aluminum. Buy 'em by the box from Avery (20 pads/box). Get
the 7A medium grade wheel from Avery for your grinder (6"). Not cheap
($43), but given proper care, it should last the project. Buy several of
the smaller wheels--they don't last as long.

+++ #1744
From: Tim Anderson  <fuzzet@h...> 
Subject: [Bearhawk] Re: Scotchbrite 

Maybe it's just me (or my poor handling/stacking skills) but I have a
lot of scrach marks on my rib blanks, during cutting, drilling, forming.
I have been using both maroon pads and/or 400 grit wet/dry sandpaper
(with water).  The pads seem to work good on the edges and the wet paper
does a nice job on the scraches.  I should probably get some fine scotch
pads.  The wet paper does make things a bit messy.

I wish there was a way of appling a thin protective peel off coating to
the alum, to prevent handly scratches.  Oh well.  maybe wrapping the
darn thing in plastic suran wrap would work.  Or maybe there is a
spray-on coating.

+++ #1754
From: Bearhawk390  <Bearhawk390@a...> 
Subject: [Bearhawk] Re: Scotchbrite 

i took a sheet metal coarse from Sportair last year and the instructor
recommended coating your aluminum with ZinkCromate before you start to
work it. i tried it and it works great, only takes a VERY light coating
you can brush or spray on. Available at wicks, if you don't want to use
it as your permanent corrosion protection it will wipe right off with
lacquer thinner when your finished good luck.

+++ #1756
From: Donald Schindler  <t18skyguy@h...> 
Subject: [Bearhawk] Re: Scotchbrite 

Another thing the old pro's used to do was to dip their rivets in Zinc
Chromate before they bucked them. It gave real good corrosion proofing
and after it dried, if you had to drill the rivet out, the chromate
would hold it and keep it from spinning. Im not an old pro Im just old.

+++ #1771
From: Donald Schindler  <t18skyguy@h...> 
Subject: [Bearhawk] Re: Tack welding 

Kelvin, I think that you might just need to do more jigging before you
pick up your torch. If you've never tried Mig welding you may have a
tougher time with a tack than with gas, particularly on vertical tacks
and nearly impossible overhead. To help your jigging get a set of
Lowbuck adjustable tubing clamps(www.lowbucktools.com) they help alot. I
prefer TIG myself but it is a fact that Mig is employed by numerous
aircraft manufacturers(Kitfox, Mooney, Bellanca) for it's speed.

+++ #1785
From: Tony Dean  <tdean@d...> 
Subject: [Bearhawk] Re: Tack welding 

The snippet below raised a question about preparation and setup. I plan
to seal my tubes with line oil and that means that I have to drill holes
for the oil to enter the uprights and diagonals. If you tack weld, do
you drill all the holes for uprights and diagonal tubes before tacking
(I presume you do)? Or, would you simply not oil treat the uprights and
diagonals?

The examples I have seen are ones where the oil holes are drilled and
after the fuselage is completed you turn it up on end and pour hot oil
in one end and let it flow throughout the tubes.

Any ideas? 

+++ #1786
From: Russ Erb  <erbman@c...> 
Subject: [Bearhawk] Re: Tack welding 

> If you tack weld, do you drill all the holes for uprights and diagonal
> tubes before tacking (I presume you do)? Or, would you simply not oil
> treat the uprights and diagonals?

I plan to oil the tubes (another controversial topic if you talk to
Richard Finch). The trick is remembering to drill the little hole before
tacking the tubes in place.

Poly-Fiber sells a good line oil for anyone looking for a source.

+++ #1788
From: Bruce A. Frank  <BAFRANK@w...> 
Subject: [Bearhawk] Re: Tack welding 

I would drill holes allowing communication between all the tubes. I
started with a salvaged fuselage which did not have holes between any of
the existing tubes. For all of the new structure I added I first drilled
an eighth inch hole to allow this free communication between longerons,
diagonals and vertical tubes. For the tubes already in place I drilled
through from the outside of the longerons, up through the clusters, into
each of the tubes. I then welded up the remaining hole in the outside of
the longeron.

+++ #1797
From: Zippydogg  <Zippydogg@a...> 
Subject: [Bearhawk] Re: Tack welding 

I was thinking of interconnecting all the major tubes in the fuselage,
and plug the ends. I would then install a shrader valve (tire stem) and
pressure gage. After welding is complete, but before the first flight,
the time required to "leak down" from some particular pressure would be
measured.  Then periodically, I could accomplish the same test. A
shorter time to "lead down" may indicate a crack. This would also be a
good way to get the tubes completely sealed. IMHO this would be the best
rust prevention measure.

This method was used on the Porsche race car frames in the distance
past.

+++ #1798
From: Russ Erb  <erbman@c...> 
Subject: [Bearhawk] Re: Tack welding 

> I was thinking of interconnecting all the major tubes in the fuselage,
> and plug the ends. I would then install a shrader valve (tire stem)
> and pressure gage. After welding is complete, but before the first
> flight, the time required to "leak down" from some particular pressure
> would be measured.  Then periodically, I could accomplish the same
> test. A shorter time to "lead down" may indicate a crack. This would
> also be a good way to get the tubes completely sealed. IMHO this would
> be the best rust prevention measure.  This method was used on the
> Porsche race car frames in the distance past.

I've heard of this method. In fact, it is mentioned on page 112 of the
EAA "Aircraft Welding" book. What you didn't mention is that it involves
filling the tubes with nitrogen--you have to get the oxygen out for it
to work. Have fun finding those pin-hole leaks that always seem to
exist.

If you use line oil, the stuff has such incredible capillary action that
it will work it's way out of pinhole leaks. Leaving the pin hole leaks
in probably wouldn't be a problem from a corrosion standpoint, but it
would be so ugly to have it come out on your fabric.

Either way, you still have to remember to drill those holes!

+++ #1800
From: Bruce A. Frank  <BAFRANK@w...> 
Subject: [Bearhawk] Re: Tack welding 

After the fabric is on what do you plan to do if the pressure gauge
shows you have a leak? Cut off the fabric? How are you going to find
that leak?  Just put connecting holes in all the tubes and install line
or linseed oil.  The oil will clot and seal any pin holes. You may be
loosing sight of what you're trying to accomplish. Oxygen inside the
tube in a fully sealed system presents no rust problem. A little light
haze rust forms on the inner surface of the tube and that is it. Once
the small amount of oxygen has reacted with the surface of the steel no
further rusting can take place. The object is to prevent "breathing" of
the tube during barometric pressure and temperature changes. Such
breathing carries in fresh oxygen (necessary for rusting) and moisture.

With the system oiled, besides sealing any pin holes, the oil eats up
any free oxygen. With no free oxygen, even with water present, no
rusting takes place. If a small crack eventually forms (no single crack
is going to cause catastrophic failure in these truss style tube frames)
it is likely the internal coating of oil will continue to protect the
tube. It is also likely that remaining liquid will seal that new crack
to continue to protect the tubes.

I have welded tube frames that showed absolutely no leak down over 4
weeks.  But once the frame was put in service the pressure leaked
out. No crack, just a pinhole unclogging from the bumps and
flexing. Linseed oil prevents such a problem.

I once cut apart a gear leg from a TriPacer that had been rebuilt 30
years in the past. It had been oiled when rebuild (though the original
Piper leg was not). When I opened up the rear tube of the leg it
contained about 8 oz of water and 4 to 5 oz of still liquid linseed
oil. There was not one speck of rust in that tube(the plane had been in
dry storage for 15 years).  I actually sawed it full length to be sure
that there was no rust present.  Don't know how the water got there, but
the oil still did its job. Use the oil and don't worry about all those
"what ifs".

+++ #1802
From: Tim Anderson  <fuzzet@h...> 
Subject: [Bearhawk] Re: Tack welding 

General questions on the oiling process.  Correct me if I'm wrong.

1.  Drill all interconnecting holes at tube joint locations (prior to 
welding)  Bruce your drawing is great.
2. weld the frame completely
3.  poor in hot linseed oil to several locations?  How much?
4.  seal up the tubes
5.  rotate the frame to prevent pooling?

But how does one prevent oil pooling at the low spot in the frame when
all the tubes have interconnected drain holes.  On the taildrager, all
the oil will end up in the lower tail (which is probably where any water
or condensation will also pool).  The top of the fuselage will never see
oil after the initial application.

+++ #1804
From: Russ Erb  <erbman@c...> 
Subject: [Bearhawk] Re: Tack welding 

> But how does one prevent oil pooling at the low spot in the frame when
> all the tubes have interconnected drain holes. On the taildrager, all
> the oil will end up in the lower tail (which is probably where any
> water or condensation will also pool). The top of the fuselage will
> never see oil after the initial application.

Line oil (Poly Fiber Tube Seal) has incredible capillary action such
that it will climb up the inside of the tubes against gravity. I can't
tell you why it does that but I've seen it happen. Thus the oil will
stay in the top tubes. Oil pooling at the tail is not a problem (only a
few ounces of weight), and a good place to have it if that's where the
water collects.

+++ #1806
From: budd davisson  <budd@g...> 
Subject: [Bearhawk] tube oiling 

Bruce brought up an important point about internal corrosion: it needs
oxygen to happen. I don't know the percentage, but a major percentage of
the old fuselages weren't oiled on the inside and many just oiled the
longerons. Drilling and oiling all the diagonals is a great preventative
measure but in cutting up and repairing dozens and dozens of old
fuselages, I don't think I've run into internal corosion more than a
couple of times and then it was the result of exterior rust pinholing
the tube and letting air/moisture in. Sloshing line oil in there and
making sure every tube is sealed will make it last into the next
century. Sloshing the oil in and not welding everything as tightly
closed as possible, may let oxygen do it's thing, dispite the oil.

Another thing, is making certain the exterior of every cluster joint is
completely clean before painting it. If a piece of scale flakes off
after painting it, all the line oil in the world won't help, as it'll
start rusting from the outside. We have a local powder coating outfit
that does a terrific job of gently (repeat, gently) blasting a fuselage
and then powder coats it any color you want for $300. I think it's worth
the investment.

Incidentally, safely sand blasting fuselages is an art: don't turn it
loose with your local pool contractor. 

+++ #1815
From: budd davisson  <budd@g...> 
Subject: [Bearhawk] Re: ADEL clamps 

How about bandsawing a wide notch, the width of the bolt, in the nose of
a cheap pair of vice grips and maybe grind the nose down so they are
pretty thin. Clamp over the adel and slip the bolt through the notch.

just thinking. 

+++ #1816
From: Derrick Howard  <derrickhoward@h...> 
Subject: [Bearhawk] Re: ADEL clamps 

You can use waxed tie string(used to tie up wire bundles)looped & tied
through the bolt hole. The wax will keep the clamp closed, still able to
get the bolt in(barely), & you can either leave the string tied, or cut
it away.

+++ #1817
From: Tim Anderson  <fuzzet@h...> 
Subject: [Bearhawk] Re: ADEL clamps 

My thoughts exactly.  Maybe two flat plates welded or BRAZED on the jaws
with a slot for the bolt/nut.

+++ #1822
From: Russ Erb  <erbman@c...> 
Subject: [Bearhawk] ADEL clamps 

One answer to ADEL clamps is just plan to be frustrated. Vise-grips are
a definite plus.

I like the safety wire idea--that never occurred to me.

Here one I developed for a specific condition. My main wiring conduit is
held in with ADEL clamps, and I realized that I had cleverly placed it
through the lightening holes in the nose ribs in such a way that I
couldn't get my arm through the lightening holes in the main spar to
buck the rivets on the nose skins. The conduit was just in the way. I
had already installed all of the brackets to hold the conduit and liked
the way they turned out. There were several options:

1. Leave the conduit in place and use blind rivets to attach the nose
skins (No good--lose most of the cool points gained from flying a
Bearhawk, especially around other Bearhawk builders. Not to mention the
question of 1) rivet strength, or 2) cost of that many cherry max
structural rivets).

2. Cut seven more access panels in the bottom of the wing (Too much
work, also ugly)

3. The answer: Pre-attach the clamps to the conduit using machine screws
and thin jam nuts. This holds the clamps in place. After riveting the
nose skin on, slide the conduit in place, insert remaining end of
machine screw through bracket, and install nylon stop nut. I have
checked and there is sufficient room to do this at each location either
through the lightening holes in the spar or access panels installed for
other purposes.  The intent is that the conduit would never have to be
removed. For the very small probability that it did, a few new access
panels would have to be installed.

+++ #2112
From: bearhwk272  <bearhwk272@a...> 
Subject: Fire in the workshop ! 

Just a friendly safety reminder.  If you happen to own and use a belt
sander, with or without a dust collection system be cautious of the
following.

Sand a bunch of wood for tooling and household projects, sand a bit of
aluminum for the Bearhawk, sand 4130 for flap and aileron hardware....
AND POOF FIRE in the belt sander guard. Various material buildups had
occurred in the pulley hubs and "dead" areas that just managed to ignite
from the steel sanding sparks.

No harm done this time. Hate to think what might have happened if it had
migrated into the dust collector / Shop Vac.

Back to sanding.

+++ #2116
From: Russ Erb  <erbman@c...> 
Subject: [Bearhawk] Fire in the workshop ! 

FIRE IN THE HOLE!!!

Excellent point, Kevin, and one I had not thought about.

I keep a fire extinguisher handy in the workshop.  Its expected use was
primarily during welding, but would be good for this case too.  While
welding I also have another system available--the faucet on the sink in
the shop has a hose thread on the end.  I attach a garden hose to the
faucet, and a spray nozzle to the other end.  Water on full pressure,
with the nozzle in a bucket in case it leaks.  If fire breaks out
(beyond minor scorching of plywood that can be blown out), grab the
nozzle, squeeze, and its gone.  Won't do wonders for the temper of your
weld joint, but at that point the weld is way down the priority scale.
Haven't had to use it yet, but I'd much rather have it there and not
need it than the other way around.  If you don't have a sink available,
you can run a hose in from the back yard.

+++ #2158
From: Bill Cox  <t18cox@f...> 
Subject: Re: [Bearhawk] Other - New Airstrip 

I have a tube notcher (ol Joint Jigger), but usually use a pair of
compound snips and finish with a file. My neighbor uses his quite a bit,
so I guess its what you get use to. His is from Harbor Freight and it's
an exact knockoff at less than half the price.  The welding gets easier
with practice. It sounds like you got the fundamentals. Same with the
riveting, you'll probalbly buck most of your own rivets.  I spent a bit
of time with the Lincoln folks learning to weld Al with the Lincoln
175. I did alright with him looking over my shoulder coaching, will I do
OK on my own? We'll see next week.  Sounds like you made a good haul. I
believe I have every thing for the wings. The skins are on the way from
Airparts.

+++ #2175
From: Mike Eldredge  <meldredge@a...> 
Subject: Re: [Bearhawk] Welding fuse clusters 

What kind of tubing cutter did you buy that you don't think you will use
much?  I ask because I'm considering buying the tubing notcher from
Harbor Freight.  What do they recommend for cutting?

+++#2178
From: Kelvin Gurney  <kgurney@k...> 
Subject: Re: [Bearhawk] Welding fuse clusters 

I bought the expensive one listed in most aviation magazines.  I have
heard the Harbor Freight notcher is an acceptable copy.  I made that
comment because they show a technique using tin snips and a bench top
grinder that combines the measuring, cutting, and fitting into one fluid
operation.  I have played around with my notcher to get a feel for it.
I think there are two disadvantages to the notcher:
       a) Clamping and unclamping the tube every time you want to make a
cut takes time.
       b) Measuring the angle and transferring that angle to the notcher
takes time and is prone to error.

The advantage to their technique is:
       a) It's quicker.  You are making the cuts standing at the fuselage
jig. No clamping and unclamping of tubes.
       b) It's intuitive.  You mark the angle with your thumb and make
small cuts.  Less chance of error.

I think the notcher is useful.  I would guess where you have complicated
clusters the time spent setting it up and running test cuts would pay
off.  It just after seeing the video I realized there was a quicker,
simpler way.

Keep in mind, this is the opinion of someone who has yet to build his
first fuselage.

+++ #2179
From: Bill Cox  <t18cox@f...> 
Subject: Re: [Bearhawk] Welding fuse clusters 

I have the high dollar notcher, my neighbor has the Harbor Freight
model.  They appear to be nearly identical. He builds fuselages for an
ultralight kit and uses his to some extent. He also cuts a lot of tubes
useing a reamer in his lathe. I mostly use the snip, file, grind
method. It seems to go the quickest.

+++ #2180
From: Bob Romanko  <romanko@v...> 
Subject: RE: [Bearhawk] Welding fuse clusters 

For what it's worth.....

In 1981 I went 21 months through my A&P school, and there wasn't a
tubing notcher in site.  I passed my FAA Airframe practical exam with a
cluster weld done entirely with snips and a rounded wheel on a grinder.
Once I got the hang of the technique I can't imagine how I could make a
joint any faster with a notcher.

+++ #2184
From: budd davisson  <budd@g...> 
Subject: Re: fitting tubing 

Yet another opinion, 

Don't complicate your life by a) trying to get absolutely perfectly
symetrical fits and b) by using something that adds time to notching the
tubing.

IN the first place the fits don't have to be perfect. Remember you're
going to melt most of the edge so if it is a little rough, it doesn't
make any difference. The tiny sharp corners caused by the edge of a
griding wheel melt first and smooth out with the rest of the puddle.
What you don't want is tubing touching tubing,because it needs a little
space to expand. A .030-.040 gap, or the thickness of a handsaw blade,
is okay, but it doesn't have to be perfectly even and tight unless
you're tigging, which works better withtight fits.

Setting up the tubing notvcher and all that takes unnecessary time.
Every single person reading this has their own method and Iv'e used most
of them. I finally settled on dressing my grinder wheels to a point, not
a radius. I lay the tubing in place and make a mark that runs across the
diagonal and overlays the cenerline of the longeron or cluster centers.
That gives me the angle to cut it, which I do on a cheap metal cutting
band saw.

Before I cut it, however, I mark the end of the diagonal front and back
(fore and aft on the airframe), paralleling the longerons. This helps me
keep the radii at each end lined up.

I then grind a deep notch on each side of the diagonal where the
centerline marks were with the pointed wheel. I take a short piece of
scrap tubing of the size the diagonal is going to meet and use it to
draw a rough radius around those notches. Then I grind to that mark
using the sharp edge of the wheel to "wipe" the metal away.

If it takes 5-8 minutes an end to do all of this, it is a lot. For those
of you have haven't put a piece of .035/49 to a bench grinder: it
disappears in a hurry.

I fit one end before I notch the other end, that way I can make sure the
notches parallel and the length is right. 

In my mind, it's better to do it fast, rather than perfect, because then
you don't have much time invested in it and you are perfectly willing to
scrap the piece and do it again. If it has taken you 15 or 20 minutes,
between measuring, setting up the tubing notcher (it's easy to get the
centerlines wrong and cut a piece "just a little" too short and be
tempted to use it) per end, you're going to be less willing to start
over.

And don't worry about wasting the piece of tubing. If there is one truth
in scratch building, it is that there ain't no such thing as too much
scrap tubing. You'll use it up for something. 

Like I said, yet another opinion. Take it for what it's worth. 

+++ #2189
From: Bruce A. Frank  <BAFRANK@w...> 
Subject: Re: [Bearhawk] Welding fuse clusters 

I have always found the tin-snip method hard on my hands. I have a Joint
Jigger(a poor quality tool when more than a couple of hundred joints
need to be fish-mouthed) that I use extensively to build engine mounts
and landing gear for the V-6 STOL, but I know all the angles and lengths
so it's a fast process for me.(Actually, I now use a similar tool built
by Elwyn Johnson, when he owned Northwest Aero, that uses hardened parts
and roller bearings. It has produced several thousand notches without a
problem) If you are building a one off fuselage there is nothing faster
than a bench top grinder with wheel dressed to a radius, rather than
flat.  An end of 1/2" or 5/8" diameter .035" or .049" wall tube can be
ground to shape in 30 seconds. It is a fast process. Fit up does not
have to be perfect. Even occasional gaps of 1/8" really present no
problem either with welding procedure or ultimate strength.

I also have found one of those 4.5" right angle grinders, with a hard
wheel that has its edge somewhat rounded from use, to be very handy for
notching tubes while standing right at the fuselage. I consider a file a
tool for fine, rather close tolerance work. Fuselage fit-up does not
require that precise a fit. Once in a while I'll grab a rat-tail file to
remove burrs from the inside of a tube that will sleeve another, but for
the most part files are tedious when there are 300 joints to be made.

Diagonal tubes can be a problem if the verticals and horizontals are
hard in place. An easy method I use when faced with a forgotten
diagonal, or a need to add one when making a change, is to cut a length
of tube about 2" shorter than the needed piece. Cope both ends to fit
the cluster into which each will fit. Then cut another 6" long piece of
the next diameter that will snuggly slip over the first tube. Both ends
of the 6" tube should be cut at a 30 to 45 degree angle and drill
several holes suitable for rosette welding. Cut the first tube in the
middle and insert the pieces, center cut end first, into the 6"
sleeve. Slide the inner tubes out to fit into each position in their
clusters, center the sleeve, tack all contact points, then weld the
clusters, rosettes, and the angle cut ends of the sleeve. You then have
an easily fit solid diagonal with little extra weight and no gob-on
welds needed to fill the gaps needed to insert a full length diagonal.

+++ #2491
From: Russ Erb  <erbman@c...> 
Subject: Re: [Bearhawk] Short-Winged bearhawk Club 

I agree that the fan rivet spacer is well worth the money. I use mine
frequently. However, I must differ with Forrest on one point. The
instructions that came with it said do NOT use it as a drill guide.
Besides the inevitable enlarging of the holes, you'll end up with a
non-straight line of rivets. The technique is to draw a line, mark the
locations with the tool, then drill on the line where the marks are. If
you do this you will see that the holes in the spacer don't stay
perfectly lined up but form a slight arc when the tool is expanded. I
haven't worked out the geometry as to why yet. Clecoing the end points
in does work very nicely if you can do it.

+++ # 2499
From: mailstuff  <theferdons@m...> 
Subject: Re: [Bearhawk] Short-Winged bearhawk Club 

You have to be careful when you drill through the rivit spacer, but it
can be done.  I have one that is five years old and it still holds a #3
cleco just fine.  Another thing you can do is use a spring loaded punch
to mark the locations and then remove it and drill at the pricks.

+++ #2580
From: Bob Romanko  <romanko@v...> 
Subject: Leather Mallet/Hammer Source? 

I'm looking for an old ratty leather-faced hammer like we used at PIA
back in 1979. No luck. Who the heck sells these things? I'm bangin' ribs
with plastic, but much of the nostalgia is lost. It's just not the
same. Call me a traditionalist.

I'm tempted to get some 2" hickory, cut up one of my wife's (many)
handbags, and just build my own. That WOULD be in keeping with the
Bearhawk tradition.

I've searched all over the web, and can't find a source anywhere.

Howsaboutalittlehelp?

Thanks, folks. And WATCH that rivet spacing out there!

+++ #2581
From: budd davisson  <budd@g...> 
Subject: Re: [Bearhawk] Leather Mallet/Hammer Source? 

I am now officially let down in Bob "don't use anything that's already
made" Romanko. Cutting up purses when you could be out there growing the
cows, preferrably thick skinned ones?

Try the "tin man's" website. I don't have the URL but someone will. 

And don't cut up the purses, go buy a couple of sole blanks from your
local shoe guy. It's nice thick stuff.

+++ #2583
From: Bruce A. Frank  <BAFRANK@w...> 
Subject: Re: [Bearhawk] Leather Mallet/Hammer Source? 

> I'm looking for an old ratty leather-faced hammer like we used at PIA
> back in 1979.

Have you tried Brookstone or McMaster-Carr?

+++ #2584
Bion Rogers  <rogersbc@s...> 
Subject: Re: Leather Mallet/Hammer Source? 

The following is available from Brownells, a gunsmithing tools supplier.
They have a wonderful warranty ( If your not happy with it, send it back
for refund or replacement)I use them in my gunshop all the time.

These are the old style thick layer wrapped, boiled in wax, animal glued
kind that everyone wants but always says they can't find them Made in
the USA.

Brownells has many hand tools that are impossible to procure anywhere
else, and I'm not just talking about gun tools or parts.

This is from their on-line catalog at brownells.com 

    Perfect "Soft Touch" For Wood & Finished Metal Great for gently tapping
    on a barreled action during inletting or driving a 1911 slide back and
    forth when lapping it to the frame.  Won't mar wood or metal. Head is
    made entirely of rolled rawhide.  White hickory handle.

    SPECS: Rawhide Mallet No. 1, 4 oz. (113g) head, 11/4" (3.2cm) dia. x
    31/8" (7.9cm). No. 3, 8 oz. (226g) head, 13/4" (4.4cm) dia. x 33/8"
    (8.6cm). Head lengths and dia. will vary with the density of the hide
    but will normally be within 1/2 oz. of specification.

    Stock No.
    Product Price Qty.    
    672-196-001 Rawhide Mallet No. 1 $17.10     
    672-196-003 Rawhide Mallet No. 3 $24.85     

+++ #2634
Doug Knight  <metalfab@p...> 
Subject: Re: [Bearhawk] Seeds, Skinning Cats, and Brown Trucks 

Against my better judgment, "a cobbler's kid has no shoes."

I'm right on the edge on making a commitment on building various
tooling and jig fixtures for rent.

What I need is a little feed back for planning and design
engineering.  My current thoughts are wood is fine for one off,
where metal dies would last a little longer. Some how there would
have to be set a standardized hole and finish process regime to
allow the dies to have a long cycle life. If the field builder has
improper holes sizes and poorly hole edge deburing and scotch brite
finish.

With that said I currently am thinking of 7075 dies and
shoes. Singles for each hole sizes. These would work to with either
all thread compression or in a press depending on what you have in
your home shop.

Now for what I do at my work, I am the lead fabricator/welder in a
small fabrication company that builds theme park structures and
theater set, and for rock and roll touring shows. There I build all
the tooling and jig fixtures that produce either one or multi copies
of parts. The inventive process is a daily thing for me.

So what other tooling and fixtures you guys think might have a need
for?

And for those interest I haven't Gas welded in over 30 years and
plan to do ALL my welding with Tig. I have several heat treaters
here in town that could normalize my fuse when finished. Maybe I'll
have it powder coated too, that guy lives 4 houses down the street
from me. I think of a tube fuselage as just a micro truss.

+++ #2902
From: Bob Romanko  <romanko@v...>
Subject: RE: [Bearhawk]brakes and stuff

You have a good point about the space.  That's why I designed my shop
from the ground up.  I used pole construction so I can knock out wall
panels on opposite sides and hang the wings ala T-hangar.  I also built
a second floor to store parts and materials.  It's pretty interesting
when folks drop by to see the "Bearhawk" and don't see anything but the
part I'm building at the time.  When I finish with a set of ribs I store
them upstairs, so I rarely have more than twenty or so blanks on my
bench at any one time.  If you look at my build log and then look at my
shop, you'd be quick to call me a liar!  I guess until I start pounding
the spar together, the shop's going to be pretty bare.  One thing I
learned from visiting other builders is that most of their space is
taken up by part storage and Christmas decorations, not necessarily with
tools.  Sure, not everyone has the luxury I was blessed with, to be able
to build a shop for the purpose of Bearhawk construction.  I do,
however, think that for quite a few folks it would make sense to find
someplace else to store the parts and household items that take up
valuable shop space.  Some of the U-Store-It places around here are dirt
cheap, and in the total cost of construction it may make sense to take
advantage of those places if it means making space for more tools
(heehee).

As an example, right now I have a tiller, lawn tractor, 55 gallon oil
drum, Shopsmith, 2-ton hoist and a push mower stored in my shop.  This
is driving me bonkers.

I'm building another building, a shed, that will be 12'x16' with ten
foot ceilings and a 12/12 pitch roof for rafter storage.  I thought that
having those things in my shop wouldn't be a big deal, but every morning
when I'm pounding/cutting/polishing aluminum I'm looking at them
"invading my Bearhawk Sanctuary".  Not good.  Justifying to my wife that
I need another 192 square feet after just building a shop that's 1,152
square feet hasn't been easy, but I think I'm wearing her down.  Time
will tell...

+++ #2953
From: Hedges, Bill  <wphedges@f...>
Subject: RE: [Bearhawk] back to work

What's the name of the book on fabricating tools?  I'd be interested in
making tools over buying them new.  Haven't looked too hard for used
ones yet, we have a 10 ft brake at work, all I would like is a 48 "
shear, a 48" brake, a drill press, tools like that.

+++ #2959
From: Michael Geurink  <geurink@a...>
Subject: Re: [Bearhawk] back to work

I was just reading about this book on the packrat faq.  It's Racer's
Guide to Fabricating Shop Tools.  Plug that into the title box on an
Amazon.com book search & it will come up with the book.  Only problem is
it's out of print or they have to search around to find it or something.
Since I'm in Brazil I rely on people coming down here to transport books
& parts & things I order.  Since they had no guarantee of getting it by
a certain time I couldn't get it or I'd be happy to give you a review.

+++ #2967
From:   <pfflyerz@c...>
Subject: Re: [Bearhawk] back to work

The tool fabricationbook is "The Racers Guide To Fabricating Shop
Equipment", by John Block.  There are 6 well documented plans in it,
though most of the tools are more useful to an auto builder.  There is a
plan for a nice hydraulic press.  The main reason I haven't yet put
together the parts for the brake is because it isn't a true center pivot
brake.  I don't know whether the small offset of the blade will make a
difference when bending, but I hate to build it and find I ended up with
a 40 pound boat anchor.  I will put it together some day.

+++ #2971
From: Daniel Fox  <daniel_fox@h...>
Subject: Re: Fabricating Shop Tools book

I just tried to order this book from Amazon a few weeks ago. They said
"special order wait 6 weeks." 3 weeks later they said "Sorry no can
do. We credit your account." Incidentally, I got the same thing when I
tried to order Richard Finch's guide to automotive engine conversions
for homebuilts.  Any ideas on where to source that?

I'm having a hell of a time trying to burn through this gift
certificate.  :-) Any suggestions for books for a wannabe homebuilder?

+++ #3022
Subject: Re: [Bearhawk] Other: Oil Free Air Compressor?
From: mailstuff  <theferdons@m...>

> I happened across a two year old air compressor for $200.
> It's oil free, but the specs look pretty impressive.  This
> one may be tough to pass up.  A friend is selling it:
>
> Craftsman Model #  919.152930
> H.P.     6, Direct Drive
> CFM      21.2
> Volts    240 Single Phase
> SCFM     @40psi - 15.0
> SCFM     @90psi - 11.5
>
> It has a 33 gallon tank, and it's on wheels.

If it has greater than 10 scfm at 90 psi it will run any air tool
continuously.  I have a few that are air hogs and they won't run
down a compressor of that size.  Go for it!  (mine new was $400 from
harbor freight with a 60 gallon tank - as a reference for price)

+++ #3023
Subject: [Bearhawk] Other: Oil Free Air Compressor?
From: Russ Erb  <erbman@c...>

> I happened across a two year old air compressor for $200.  It's
> oil free, but the specs look pretty impressive. This one may be
> tough to pass up. A friend is selling it:

Listen to it run first. Oil free compressors tend to be LOUD! Oiled
compressors are much quieter. I have an oil free compressor and it
is located outside the shop and plumbed in because of the noise.

+++ #3024
Subject: RE: [Bearhawk] Other: Oil Free Air Compressor?
From: Bob Romanko  <romanko@v...>

This is the $399 one from Harbor Frieght/Northern Tool I was
planning on buying before I found the used Craftsman:

Model VT 6275
6.5 HP
Vertical 60-Gallon Tank
11.5 CFM at 40 PSI
9.1 CFM at 90 PS 
125 PSI maximum
230 Volts 
Oil-lubricated
Twin cylinder
Belt-driven pump

If I just compare the ratings, other than the size of the tank and
the fact that the Craftsman is oil free and direct drive, (oh...and
it's $200 less). I'd have to say the used Craftsman seems to be the
deal.  My concern is I'm not real familiar with direct drive/oil
free compressors.  I figure if it makes it through the Bearhawk I'll
be doing fine.  Shoot, I'll probably spend more money on clecos...

+++ #3040
Subject: [Bearhawk] back to work
From: Russ Erb  <erbman@c...>

> What's the consensus on buying a shear/roller/brake? What size?
> Any other major tool suggestions for reducing the time and
> frustration without breaking the bank?

My recommendation is to first join an EAA chapter if you haven't
already.  Then find out what members have such tools that will let
you use them.  I've gotten a lot of work out of an 8' brake, 4'
shear, and bead roller that a friend has. Good thing, too, since I
wouldn't have room for them anyway.

Of course, you'll have to decide when the convenience of having your
own outweighs the cost of purchase and the space requirements.

+++ #3047
Subject: Re: [Bearhawk] back to work
From: Donald Schindler  <t18skyguy@h...>

There are alot of opinions on this but a real useful tool is the 3
in 1 brake, shear and roll like you can buy at harbor freight. It
will do alot for the money. They sell them in 30 inch and 40 inch
models. Try and hold out for the 40 inch if possible but I know alot
of guys who do fine with the 30. If you have the time to wait they
do put them on sale regularly. I have plans that I bought for a 8
foot tongue brake that if anyone is interested in I will supply info
on. It uses 4 hydraulic jacks and is not to complex as far as brakes
go. This is the type of brake they use at Boeing. It does require
some good welding though.

+++ #3049
Subject: Re: [Bearhawk] back to work
From: mailstuff  <theferdons@m...>

My dad bought a shear, press, and brake combination from Harbor
Freight and he hates it.  He has been an A&P for over 40 years and
thought this would be a nice thing for working on homebuilts.  He
stated that it takes too long to switch between the operations, it
does nothing really well, and you always have it set up for what you
don't need to do ( and after you switch it, you realize you forgot
to do something that had to be done with the previous setting) If
you are really a patient person, it will probably work fine.  My dad
hates to spend a lot of time setting up a tool.  You better have a
good bench, because these things are really heavy!

+++ #3117
Subject: RE: [Bearhawk] Tool sources
From: Bob Romanko  <romanko@v...>

Good advice.  If you go to an auction, even if something doesn't
work, you can collect enough junk to make one good compressor if
you're patient.  I picked up a VERY nice 30 gallon tank and pump
with no motor for $10 at the University of Virginia auction.  It's
still not what I'm looking for, but better than what I had.

Don't worry TOO much about the three phase motors.  It's not a big
deal to hook up a three phase motor to a single phase circuit.  You
can build the converter yourself, or keep your eyes out on eBay for
one.  The max HP motor one should consider for this is about 7.5HP,
which is MUCH more than the typical (but then again, few of us are
"typical") Bearhawk'er should need.  For you folks out there who
want to understand 'lectricity real good, check out this URL:

http://theoak.com/rick/Electricity_in_the_Shop.html

Good stuff there that takes you from neophyte to sparky in no time
flat.

...and yes Mr. Budd "Big Fancy Pilot/Author/Etc." Davisson, I DO
have 'lectricity on my side of the mountain!

+++ #4071
From:  "Kent White" <kent@t...>
Subject:  Re: [Bearhawk] Digest Number 232

>> Even slower yet are videos ordered from Tinman I had hand
>> carried into the country.  Here I was in the Amazon for a
>> month & a half knowing that my 4130 videos were in S o Paulo.
>> They finally arrived, and I've re-upped the itch to get
>> started again.  Just the old time/money thing in the way yet.

Just finished a 4day training here at Homebase, and had one IA
from Chugiak, AK.  BTW, the recent series of aerometal articles
in Sp. Av. are segments for the new video on Fairing
construction, and this recent Training also allowed students to
both watch and use the new Airhammer prototype dies for fairing
construction. Judging from the extruded eyeballs, this new
tooling moves the metal along quite acceptably. (The acid test
will be the polished fairings for the H1 later this spring.)
Happy students all around.

+++ #4123
From:  Russ Erb <erbman@c...>
Subject:  Safety with fiberglass cutting discs

I had a friend weld up my fuel tanks recently, and was generally
pleased with the results (read: he did a much better job than I
would have).  Of course, there were the pin-hole leaks that
always occur, but I intend to take care of those with exterior
application of some Pro-Seal.  Possible more on that later.

However, neither one of us were happy with the way one of the
filler cap flanges turned out.  Because of distortion from
welding, it was out of round and had no hope of getting the
O-ring to seal.  (Odd, considering this was the second one that
he did, and the first came out fine.)  I finally decided it had
to come off and be replaced.  The only effective method I could
find to cut it off was to use a 3" fiberglass cutoff disc in a
drill motor.

I was rather surprised at how fast the disc wore away while
cutting through the thick aluminum welding bead.  Seemed like I
was removing 2 parts disc for each 1 part aluminum removed.
Even so, it was working better than anything else.

I didn't bother wondering where all of that fiberglass was
going.  Instead, I was trying to figure out when and where to
get more to finish the job.  About the time I quit, I started to
realize where some of that fiberglass had gone.  I finally
recognized a familiar, though unwelcome, feeling.  As is my
custom, I was wearing a short-sleeve T-shirt in my heated
workshop (one space heater and a bunch of insulation does
wonders).  My arms were itching, primarily on the inside (the
part with no hair that never tans).  It was an itch that I would
get from working unprotected installing fiberglass insulation.
Hmmm, think some of those fiberglass fragments had embedded in
my arms?  That's my theory.

I put up with the itching for a while, thinking it would
eventually go away.  I woke up about 2300 still itching. For
some reason, I suddenly remembered the treatment, which I
immediately applied.  It's sort of like lint removal--Get some
sticky tape (I use plastic packing tape), apply it to the
effected area, press down, then pull it off.  RIP!  Repeat
several times.  Believe me, the itch is so annoying the pain of
hairs pulling out is actually a relief!  The idea is that the
tape is pulling out the fiberglass fragments.  This was told to
me by a composites builder.  The same problem can occur when
sanding fiberglass.

But that wasn't all.  I woke up this morning with a sore throat.
I've had lots of sore throats, but this one felt different.  I
think I inhaled some fiberglass dust and it is irritating my
throat.  Tape won't help with this one--only time.

Now, none of this is incapacitating, but why put up with the
pain/annoyance if it can be prevented.  When I finished up the
job today, I wore a long sleeve shirt.  No itchies so far.  I
also used a respirator to protect my throat.  I also used some
goggles figuring my eyes could use the same protection.

I have typically avoided using goggles (not a good practice)
because the pair I had were hard to see through and I already
wear glasses.  Those reasons seemed pretty silly when I noticed
that I could get a new pair for under $3.

While I'm at it, I'll also say that I frequently wear hearing
protection, because loud noises hurt, or are at least
uncomfortable, and I don't want to lose irreplaceable hearing
when it's easy to prevent.

Thus endeth our safety sermon for today.  Remember, practice
safety in the workshop so that when you finish your Bearhawk
you'll be able to enjoy it!

+++ #4124
From:  Benton Holzwarth <bcgh@t...>
Subject:  Safety with fiberglass cutting discs

> I have typically avoided using goggles (not a good practice)
> because the pair I had were hard to see through and I already
> wear glasses. Those reasons seemed pretty silly when I noticed
> that I could get a new pair for under $3.

 Brings to mind the story someone posted sometime back of having
been checking the action on punch and having a shard come out,
miss the goggles but embed itself in the lip.

 I took that story to heart, and bought myself a full-face
shield.  Fits over the glasses just fine, tho' does tend to fog
up bit when it's cold.

+++ #4125
From:  Jim Ash <ashcan@m...>
Subject:  Re: [Bearhawk] Safety with fiberglass cutting discs

One of the tricks a local builder taught me was to take a cold
shower as soon as you get done handling fiberglass. As cold as
you can possibly stand it. If you take a hot one, your pores
open up and the fibers can get inside them, then you itch for a
week.

I haven't had the fiberglass itchies since learning that trick
years ago.

+++ #4129
From:  Tim <tlc2@t...>
Subject:  Re: [Bearhawk] Safety with fiberglass cutting discs

I second that Jim, when building Hinckley fiberglass boats in
Maine, those words on the cold shower 'first' were instructions
from the shop foreman...Of course being 18 yrs old I just had to
find out for myself. One day after grinding decks, I reversed
the shower order.....That was 28yrs ago and I vividly remember
that night still, Mr Lobsterman, wicked/brutal.....

+++ #4131
From:  Tim <tlc2@t...>
Subject:  Safety with cutting discs

Serious business...;

Lose an eye, your depth perception and your flare....I think
about the loss of aviation when I tell myself, I don't need my
safety glass for this quick 2-second job.....My wife's uncle
lost an eye to a welding spatter, I saw it while it was going
bad about a week after medical treatment, when he lifted the
patch...

When I was in the Hospital with my Military 3degree AC joint
separation operation, a 23yr old mechanic was in the bed next to
me with a splinter in his eye, that after 2 failed attempts
still wasn't removed....He was in a lot of pain and on 100%
drugs....I was talking with his Dad, who the doctor gave the
task, to tell his boy it had to come out and I don't mean the
splinter.......I also think about that when I'm not motivated to
find that 'last resting place' of my safety glasses....

+++ #4132
From:  Bob Romanko <romanko@v...>
Subject:  RE: [Bearhawk] Safety with fiberglass cutting discs

<Snip of the fact that Erbman impregnated himself>

I think most folks are missing the boat that you impaled
yourself with fiberglass!  The velocity of the glass strands
were like thousands of little darts, blasting away at your
hairless inner arm.  AAGGHH!!!

Yup...the tape trick's the way to go.  This is NOT the time of
year for a cold shower, even here in Virginia.

Fiberglass is NASTY, and I don't care what them weenie canard
builders say.  If God had meant for planes to be made of glass
he wouldn't have given us 2024 and 4130 trees.

Speaking of losing an eye, a good friend of mine had PERFECT
vision and a not-so-perfect pair of safety glasses on.  While
operating a precision grinder, a piece of metal flew BEHIND his
glasses and struck him square in the eyeball.  After the
operation he's now tied to glasses for the rest of his life.
His good eye is still perfect.  I tried on his glasses once and
it was wild.  One lens has gobs of correction, the other is just
clear.  Totally whacked.

The irony of it all is he was using the grinder to form a piece
to go into a machine to cut eyeglass lenses.  Life's like that.

+++ #4136
From: Warren  "W. Shalm" <shalm@i...>
Subject:  Re: [Bearhawk] Safety with fiberglass cutting discs

That's a good tip on the fiberglass removal. I've used it quite
a bit on home projects but always just covered up which is
miserable in the summer.

If you're not working with fiberglass however here's a tip to
help make you more comfortable in hot climates.  I spent 15
years in India and they told us the way to avoid heat rash and
skin problems from perspiration and body salts etc. was to first
take a hot shower to open the pores and flush them out, then
cool off with cold if you need to. It really works even though
most of my Canadian friends think I'm nuts. Oh well, let 'em
scratch.

+++ #4148
From:  Shelly <shell@i...>
Subject:  Re: [Bearhawk] Safety with fiberglass cutting discs

> The only effective method I could find to cut it off was to
> use a 3" fiberglass cutoff disc in a drill motor.

I wonder if part of your problem is the type of cut-off wheel
you are using.  I have been using a 1.5" "fibre-cut" (aluminum
oxide) discs for general cut-off jubs on just about every kind
of material for about 30 years with never a problem. They are
made by Dedeco Co.  If you think you would like to try one, I'd
be glad to send you one - or I can tell you where to order.  I
use it in a small Ryobi high speed.

+++ #4155
From:  "Donald Schindler" <t18skyguy@h...>
Subject:  Re: [Bearhawk] Safety with fiberglass cutting discs

I dont think it would be over-kill to maybe call a physician and
mention your experience. You say your throat is sore but the
real problem might be a little deeper in your lungs. Repeated
exposure to fiberglass dust will certainly bring on emphysema
but this is the first time for you right?  Maybe an over the
counter expectorant might help bring it up. Guard those lungs
and eyes.

+++ #4156
From:  BruceAFrank@a...
Subject:  Re: [Bearhawk] Safety with fiberglass cutting discs

It is a good idea to protect your lungs from fiberglas dust. Any
particulate can cause problems, but we are not talking Asbestos
or Berilum (sp?) here.  Fiberglas particles are moved out of the
lungs fairly well over time with no real long term impact. The
throat irritation could easily be from the powdered epoxy binder
used to make the wheel. If you breath through your nose you'd be
surprised at how little of such particulate actually gets to
your lungs.

I am not saying don't take care, but there were no real long
term problems created during this one incident. Oh, I consider
aluminum dust MORE of a hazard because of its reactiveness and
its oxide crystal structure.

+++ #4229
From:  budd davisson <budd@g...>
Subject:  Re:variations on explosive forming

Re: alternate forming techniques

In my one and only regular job since graduating college, for a
couple of years I was based at the duPont lab in NJ where, among
other things, they/we developed explosive cladding, which is how
the original billets for laminated quarters (coins) were made,
and we did some explosive forming. Most of this was done with
Detasheet (spelling?) which was a sheet form of primacord. They
did some really neat stuff, including forming one inch steel
plate for boiler ends, but I haven't heard anyting about it
since then. Incidentally, this was all done under water which
provided much of the needed resistance to direct the explosion.

Another method, I haven't heard anyone mention lately, is
directly applicable to homebuilts. I once saw cowl bumps being
formed via a unique method: rather than pounding them down into
a female mold, a steel plate was screwed to the mold capturing
the aluminum sheeting under it. The plate had a grease zerk
screwed into it and then grease was simply pumped in via a
normal grease gun. Enough pressure was developed to push the
aluminum, without hammer marks, into the mold.  They had an
secondary method in which the sheet was trapped between two
steel plates, one with the cut out of the part to be made, and
they simply blew it up with grease, like making a small free
blown canopy but in aluminum. Very cute method!  bd

+++ #4232
From:  "Kent White" <kent@t...>
Subject:  Re: [Bearhawk] Re:variations on explosive forming

Detasheet is used by artists, still.  One gal, down in AZ back
in '90, was forming 5'X10' cor-ten a half inch thick using the
stuff, and the female was a concrete bas relief.  Took her a
while to find the finished part, but that is why she used the
desert for her workshop.

Grease-gun forming, either free or captured is widely-known
amongst older airplane folk.  Our video on Fluid Forming is a
variation, and uses a cheap pressure washer to inflate
various-sized stainless, copper, aluminum, and steel sections
for art, aircraft, and murdercycles.

Rohr and GenDyn used to use electro-hydraulic forming, where an
aluminum wire in a water column was fired by a huge bank of
capacitors. Charge the caps, jolt the wire, shock wave goes
through noncompressible "dolly" and the wave forms the
part. Ka-Whoom!

Explosive forging will do heavy sections in exotic alloys (Renee
41) with much finer detail and weight-savings than other slower
methods.

Cylinders and tubes may be bulged and contoured without having
to withdraw complex interior die sections. Multiple metals may
be formed together and sealed pressure tight without welding
operations.

If using water, there must be air between the dies and the blank
to avoid weird displacement problems. Standoff is important.
---And always use a neighbor's pool. The water spout is a fine
spectacle, but can empty the pool, and leave the condition of
the bottom exposed to scrutiny.

+++ # 4249
From:  Russ Erb <erbman@c...>
Subject:  A truly useful but cheap tool

At some point in your construction, probably after finishing
your ribs and spars, you'll need to start laying out a bunch of
stuff.  This involves drawing a whole mess of lines.  Just like
when you were in school, this will require copious use of a
straightedge.

I got my most useful and favorite straightedge quite by
accident.  It started out life as a leftover strip of 0.025
aluminum from making blanks for the rib stiffener angles.  Thus
it is a little over 1 inch wide and about 3 feet long.  It was
cut on a 4 foot shear, so I know the edge is straight.

I have used other straightedges, of course.  When I've needed
something shorter, I've used the 6" or 12" rules from a couple
of combination squares.  For really long lines, I've used an
(aluminum) 4 foot drywall square.  On occasion I've also picked
up a piece of fuel tank strap (1" x .025 4130 steel).

So why is my favorite my favorite?  Two reasons:

1.  It's flexible, so it will bend with the surface of the wing,
such as drawing the centerlines of the ribs on the wing skin
while the skin is on the ribs.  The rules from the combination
squares are stiff and won't bend (more than once).  The drywall
square is too unwieldy and heavy for most jobs.

2.  (The main reason) For reasons I can't fully explain, any
steel rules (or the steel straps) are hard to slide on the
aluminum sheet to get in just the right position.  My best guess
is that the edges are trying to dig in to the aluminum, and the
aluminum is just gummy enough to catch the edge.  In contrast,
the aluminum straightedge slides into position very easily.
Much nicer.

I also took a similar piece of aluminum and bent it around the
same pipe I used to form the leading edges.  I use this one to
draw lines around the sharp corners near the leading edge.

My recommendation to you is if you find access to a shear to cut
the strips for your rib stiffening angles (check with local air
conditioning contractors if all else fails), cut a few extra
strips while you're at it to use for drawing later.  Costs next
to nothing; has benefits in excess of many expensive tools.

+++ #4259
From: Corky Scott  charles.k.scott@d...
Subject:  Re: [Bearhawk] Digest Number 260

> My recommendation to you is if you find access to a shear to
> cut the strips for your rib stiffening angles (check with
> local air conditioning contractors if all else fails), cut a
> few extra strips while you're at it to use for drawing later.

When I needed to cut a bunch of aluminum in straight lines, I
used an old trick from I don't know where.  I can't even tell
you what gave me this idea but it did work.

I laid the sheet out on my thinly carpeted floor and laid a long
stiff straight edge on it and then used a very sharp carpenters
knife to score the line.  I did this very carefully the first
several passes, digging in hard the second time.  Then I made
several more passes along the scored line pressing as hard as I
dared.

I flipped the sheet over and using the same stiff straight edge,
laid it along the scored mark which was obvious from the indent
I could see on the backside of the sheet.  Then I was a matter
of bending it back against the straight edge as I stood on it.

The sheet gave right as the score mark and rocking it back and
forth caused it to fatigue along the line.

This left a lot of filing to do to clean up the edge but when
you don't have the right tool (wide sheet metal shear) labor is
cheap.

+++ #4430
From:  Bob Romanko <romanko@v...>
Subject:  Other: Nice Micrometer Set on Ebay

Not mine, I already have a 0-6" ST set.  I REALLY like
Scherr-Tumico micrometers, and noticed this set on eBay ending
at around 1700 EST today, January 8th.

http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=535451895

The set new is around $700.  I have no interest in this set, but
thought fellow Bearhawkers may want to be aware.  I like these
more than those from Starrett or Brown Sharpe.

+++ #4481
From:  budd davisson <budd@g...>
Subject:  Re: [Bearhawk] media blasters

Re: Small parts blasting

Somewhere I saw the plans for a homemade blasting cabinet built
around a siphon blaster. It seems to me they were being sold by
TP, the same folks who make a wide range of blasters and
cabinets. They have lots of neat, applicable stuff,
www.tptools.com.

+++ #4487
From:  "DANFORD, GARY" <Gary.Danford@D...>
Subject:  RE: [Bearhawk] media blasters

I have been working on cars, pickup's, lawnmowers and airplanes
for years and don't see how you can get by without a sand
blaster.  Your welding immediately gets better because you don't
have to weld thru slag.  The sand blaster takes the surface
tension from welds and the paint sticks.

I would suggest[http://www.tptools.com].  They sell a
sandblaster kit with plans for the cabinet for around $149.00.
The cabinet requires 2 sheets of plywood and you're in business.
Mine works great and wouldn't be without it.  You can also call
them at 1-800-321-9260.

+++ #4548
From:  Russ Erb <erbman@c...>
Subject:  Re: [Bearhawk] media blasters


> Cooling plenum? do tell! I've had a real problem with water
> while painting and I'm willing to try anything to fix it
> (short of hiring out the process ;-).

I figured someone would bite on that phrase.  Ken, it's a fancy
name for a fairly simple concept.

When I lived in Colorado, I had the air compressor in the garage
(noisy damn thing) with the air piped down to the basement.
Originally I had the filter/dryer (the thing that looks like it
has a gascolator bowl on the bottom) all of 18" from the
compressor.  In several years, I never saw any water trapped in
it.  Granted, Colorado Springs is drier than a lot of places,
but not that dry.

I moved the filter/dryer to the basement so that it was about 8
to 10 feet from the compressor.  Hmmm...now I'm starting to pick
up some water.  My theory is that the air coming out of the
compressor tank is still warm enough that the water won't
condense out.  Solution: Give the air some time to cool down
before getting to the filter/dryer.

Therefore, my "cooling plenum" is about 40 feet of 1" Schedule
40 PVC pipe zig-zagging downhill (to drain the water) before
getting to the filter dryer.  Granted, now I live in the desert,
but I occasionally do pick up a little water in the dryer, so
I'm guessing it's working.

All of this is kind of meaningless for painting since I'm using
water-borne Poly Fiber products...

For those of you who may be horrified at the thought of using
PVC pipe for compressed air distribution, we've already had that
discussion.  Go see the archives or the CD.  By the way, the
system is also grounded by a galvanized wire inside the pipe
connecting the brass fittings at the ends and grounded.  At
least it was when it was built--I have no idea what condition
the wire is in now.

+++ #4562
From:  Ken Beanlands <kbeanlan@s...>
Subject:  Re: [Bearhawk] media blasters

Don't be fooled in thinking that a slug of water does not affect
the AFS water-borne stuff. That is exactly what I painted the
fuselage and tail surfaces of the Christavia (and what I plan to
paint the Christavia wings and the Bearhawk) with. Fantastic
stuff. However, if you get a slug of water (it always seems to
come in a slug whrn you disturb the hoses or change the spraying
orientation) will need to be blotted off with a rag or it will
leave an unsightly run in your paint job. It doesn't seem to
affect the CecoFil that much, but it definitely hampers the
paint.

Back to your plenum. Where are your inlet and outlet with
respect to the plenum? I've seen "Drip lines" where the pipe
runs from ceiling to floor but the outlet tees off about half
way down.

+++ #4583
From:  Russ Erb <erbman@c...>
Subject:  Re: [Bearhawk] media blasters

> Don't be fooled in thinking that a slug of water does not
> affect the AFS water-borne stuff.

I wouldn't doubt that, since it would be like a slug of primer
in solvent based paints.  My point was that a little extra
humidity was not going to affect it like, say, it would dope.

> Back to your plenum. Where are your inlet and outlet with
> respect to the plenum? I've seen "Drip lines" where the pipe
> runs from ceiling to floor but the outlet tees off about half
> way down.

Can't get past this one...The hose from the compressor goes
almost straight up about 18" to the beginning of the plenum.
The pipes zig-zag downhill almost to the ground.  One leg of a
pipe tee goes to a standard female "M" style connector.
Stuffing a male connector fitting into it blows the water out of
the lowest point.  The other leg of the tee goes into the garage
and straight up about 3-1/2 feet to a manifold with two
regulators and an unregulated outlet, all connected to female
connectors.

Come on down and see it!

+++ #4611
From:  bearhwk272@a...
Subject:  Tank testing and glue

Couple quickies. 

Glue, I use quite a bit of particle board, MDF and chip board
for tooling and fixtures. Found a new to me glue this past week
that works great.  It is Elmers exterior waterproof white
glue. Duh,what's the big deal?  It is in a new format..... a
gell.... like toothpaste. Does not run, works well into the
pores of the material makes nice edge fillets, cures out much
stronger than the other glues I had used, much faster drying.

+++ #4745
From:  Benton Holzwarth <bcgh@t...>
Subject:  Fluting pliers (was: Building Status #426)

> Currently I am attempting to make the flutting pliers. I
> haven't bought a real tourch yet, so I'm working with a little
> map gas set.  It seems to be having trouble getting the pliers
> up to the right temperature. If I don't work out a solution
> soon I will probably just buy a pair of flutting pliers and
> get on with the work.

 I'm just a little ahead of you, and will share what I thought
worked for me.

 I started by filing a healthy nick onto each side of the jaw,
a'la a center-punch mark, then clamped the jaws, still pinned
together, into the vise.

 I also had trouble getting the hole drilled out.  When it
finally worked, I'm not sure it was heat that did it, but maybe
that I'd been trying to drill with a relatively small bit -- say
about 3/16" [meant to say 3/32" bjh] or 1/8" -- expecting to
work my way up.  I finally gave up, and switched to something
closer to the full 1/4" and it did finally bite in and go
without too much trouble.  (I had applied heat from a small O/A
tip, before and during the earlier drilling with no greater
success than when cold.

 I cut the piece of 3/16" rod to length and layed in the groove,
for brazing.  Doing it again, I think I'd try leaving the whole
length of the rod attached, to aid in getting the bit straight.
Mine's a little crooked.

 Having never seen a store-bought set of fluting pliers, it
wasn't clear to me just how polished they really want to be.  I
thought I'd done an appropriate job of shining 'em up, and was
merrily flanging and fluting away on my ribs, when doubts began
to crop up.  After an exchange with P-Bob, I've scrapped my
first dozen ribs, and started in on my second first-dozen.

 The pliers, as originally finished, were leaving nicks on one
side of the metal, and a frosty mark on the side against the
rod.  I believe the nicks were probably salvagable, but the
sanding and polishing marks were so gross that I just couldn't
let these be my first airplane parts.

 Here's a scan of a sample flute from the 'before' pliers:
http://www.teleport.com/~bcgh/jpegs/d9.jpeg  [now
http://www.siletzbay.com/Images/d9.jpeg  BJH ]

 Also, the nicks suggest that the metal was holding there,
rather than sliding, indicating that I was stretching the metal,
rather than pulling in a bit to form the flute.

 After more work with a file -- rounding the female jaw side and
rounding the toe off the rod; and then working 'em over with a
Scotchbrite wheel (which moved a lot more metal than I was
expecting) and polishing with emery-cloth (fold a strip so it's
grit on both sides, clamp lightly in jaws and clamp in the vise,
then run back and forth like dental floss) -- they looked pretty
good.  Then I hit 'em with the Dremel-mounted buffing wheel to
put a high shine on 'em.  (The 6" wheel just wouldn't get into
the tight spots well.)

 A trick for the Dremel tool -- I got some grocery-store
Scotchbrite pads -- the 1/4" thick green stuff.  Traced around a
coin to make circle and cut out with an Exacto knife, and
mounted in the little mandrill that came with the tool.  At
mid-speed they make good little abrasive wheels.  Less agressive
than the grinding stones, more than the cotton pad.  Don't last
too long, but only take a couple minutes to cut out a half
dozen, and a moment to change.

+++ #5002
From:  Budd Davisson <budd@g...>
Subject:  Re:Beading roller

I know a bunch of you probably already know about this, but I've
finally bought a cheap tool that works, at least for the time
being and I thought I'd pass it along.

I just bought Harbor Frieght's hand beading roller, SKU S34104,
$170 and just ran a bunch of 18 gage cold roll steel through it
(the trunk floor for my roadster). It works like a charm. A
Chinese charm, since it has Made In China stamped in so many
places it'll eventually fatigue crack through one of the "I"s.

It comes with three different size of beading rollers and three
different flanging dies. All work well.

Okay, I know some of you are frowning that I'm trading with the
Chinese.  Especially my partner. However, look at it this way:
If we buy enough of their stuff, we'll represent enough of their
market that they can't afford to nuke us. Of course, that
assumes some sort of logic reigns at the higher levels, which
I'm afraid may not be the case. So, I'll just bead the top of my
fall-out shelter a little more to ride out the attack.

Just passing it along. This would be trick for the gas tanks.

PS I just ran some .032, 2024-T3 through it and it acts as if
there's nothing between the rollers.

+++ #5003
From:  "Bill Cox" <t18cox@f...>
Subject:  Re: [Bearhawk] Re:Beading roller

That is the tool I used to bead my tanks and it works great.

+++ #5005
From:  "Tim Anderson" <fuzzet@h...>
Subject:  Re: [Bearhawk] Re:Beading roller

Harbor freight had that model on sale last month for something
like $120.  Almost bought one.

+++ #5009
From: Mark Deacon  Mark_Deacon/MSP/Mesaba%Mesaba@M...
Subject:  Re: [Bearhawk] Re:Beading roller

A friend of mine has a beading roller his dad used back in the
"good old days". I was wondering if you could use it to bead the
ribs instead of bending/cutting/drilling/deburring/riveting a
gozillion angles on the ribs?

P.S. Are there any Bearhawk builders in shootin' distance of
Detroit?

+++ #5011
From:  Budd Davisson <budd@g...>
Subject:  Re: [Bearhawk] Re:Beading roller

This is an interesting question. At some point a bead will equal
a riveted stiffener, but, for the life of me, I don't know how
to calculate the differences. I spoke with BOB about it one time
and he was skeptical. When we get everything up and running, I
think we'll do an empircal comparison. Make one each way and put
them in a loading jig to seewhich is stiffest or how much of a
bead it takes to equal a riveted angle. It would certainly make
life easier for all of us, if those little stiffeners were
eliminated.

+++ #5020
From:  Tim <tlc2@t...>
Subject:  Stiffing Beads...pics & tool pic

I've uploaded a few pages from my 2 Pazmany Builders
Manuals.....These will download automatically in just seconds,
from where you sit ;-)

NOTE: Pazmany doesn't use fluting pliers, he files notches in
his form blocks

#1....Edge radis table and how to make tool...
<http://groups.yahoo.com/group/Bearhawk/files/radius%20guage-tool.gif>

#2....Shows Beads in wooden form blocks and even a lightening
hole die
<http://groups.yahoo.com/group/Bearhawk/files/beads.gif>

#3....Shows an Aluminum beads die block....Lightening hole die
<http://groups.yahoo.com/group/Bearhawk/files/beads%20two.gif>

+++ #5021
From:  Budd Davisson <budd@g...>
Subject:  Re: [Bearhawk] Re:Beading ribs

Re: beading procedure

I think the beading could be done while the blank is still flat,
you'd just have take a round nosed bit in a router and cut
clearance grooves in the form block. I'd bet you could flange
the ribs and do the hole flanging with dies (me and Bob-sticks
don't match) and have no problems.

None of this makes any difference however, because we don't know
if this is a structurally sound alternative and won't until we
investigate it through testing. The Bob won't let it go through
any other way and he's got go, no-go approval power over the
production aspects of the kit.

+++ #5052
From:  "Kent White" <kent@t...>
Subject:  Re: [Bearhawk] Re:Beading roller

> This is an interesting question. At some point a bead will
> equal a riveted stiffener, but, ..."

Trust me on this one guys: Beadforming hardened material will
get you distortion...only.

+++ #5055
From:  "Tim Anderson" <fuzzet@h...>
Subject:  Re: [Bearhawk] Re: lightening holes

I have been using a Rotozip tool lately to auger out my larger
fuel tank holes and it works well....But it can get away from
you real quick.  For those that don't know what a rotozip tool
is, it's basically a smaller, hand-held router with small
streight bits.  I didn't use this on my lightening holes, I used
a hole cutter on my drill press and then bob-sticked.  But, the
rotozip has it's uses.  Should be able to see one at Home depot
if your interested.  $60-$70 range as I recall.

+++ #5093
From: Rob Gaddy  zipppydoggg@y...
Subject:  Re: Malco

> I'll add my experience with the malco and flycutter operations
> to the discussion.  I've had excellent results with mounting
> my router to/under my work table.

As mentioned, I used the Malco and didn't like the precision of
the hole size, or the finish on the inside of the hole.  More
time was required to smooth the inside of the hole.  I mounted
the fly cutter to a drill press (don't even think of trying to
use a hand held drill with a fly cutter) and after setting up
for a particular hole size, I set up the clamps and was able to
"drill" all the holes is short order, with precision and good
quality hole finish.  When setting up for the next hole size,
sharpen the cutter ;-).  By the way, the belt on my drill press
is "way loose", I highly recommend this since the belt would
slip when I did something stupid.  The cutter would just stop
and then I could stop the drill press motor, get unstuck and
then proceed again.

I cut my rib blanks, without lightening holes, flanged and
straightened them, then drill the lightening holes.  It worked,
nothing sayes that the lightening holes couldn't be accomplished
with the blanks are cut, but the lightening hole centers were
used for index pins during the flanging operation.

Snowed in Phoenix again

+++ #5127
From:  Budd Davisson <budd@g...>
Subject:  simple revelations

Second revelation:

I was looking for something to protect the weld table under a
weld and grabbed a apiece of scrap 20 gage steel I had been
using to learn how to use my new Harbor Frieght roller. The
piece had a couple of beads rolled in it, which acted like feet
to keep the metal off of the table top.  Again, worked great!

I then took a 6" quare piece of 20 gage and rolled a bunch of
parallel beads about 1.5" apart to use as a ready-made stand-off
for holding stuff off the bench so I can weld it.

The best stuff is always the simplest and the most obvious. Duh!

+++ #5241
From:  Budd Davisson <budd@g...>
Subject:  Re:Tinman Video

This is an unpaid for, unexpected and unsolicited review. The
subject is Tinman's (Kent White) new video called Those Darned
Saddles.

The only thing about the tape I didn't like was the title. The
rest was terrific and much of it is directly applicable to
Bearhawks.

The tape gives a blow by blow (pun intentional) account of how
to make first, a windshield fairing strip out of aluminum and
then a strut-to-wing cuff.

First a side note for doubting Thomases: there's a general
feeling that the ability to form compound parts out of aluminum
is black magic. When it comes to big parts and subtle panels,
that's right. But, wheni t comes to smaller parts like these, it
is absolutely achievable by anyone. I spent many weeks down at
Jim Younkin's watching him make similar parts and I was amazed
how quickly I picked up the ability to do these kinds of small
parts. More important, I was amazed at how much more quickly
they progressed than fiberglass. In the time it takes the
average guy to first locate the foam for a mold, glue it in
place and then get ready to shape it, he would have the aluminum
part done.

One great aspect of making aluminum small parts is that when you
make a mistake and have to start over, you only have a maximum
of 10-15 minutes tied up in it and you're perfectly willing to
make a new piece.

Now to Tinman's video:

The windshield fairing strip he was making was quite simply a
matter of understanding where to stretch it and where to shrink
it, all of which was done with a funky looking square mallet and
an easily made steel dolly (make out of pipe). I can't wait to
try it myself. Kent spends a fair amount of time showing how to
make the patterns, understand what the patterns are telling you,
and then how to make the part. very cool and fairly easy.

The wing cuff, which would go up at the top of the strut, is
made of two pieces and he shows several different ways to make
it. The inside portion, with the tight "saddle" (hence the video
name), is the tough one, but again, its a matter of making a
pattern and seeing what it tells you about where to shrink and
stretch. Making this part will produce some scrap, but I'm
willing to bet that every builder reading this will spend an
evening making scrap, think about it the next day, and the next
night will make a useable part.

Kent was welding his halves together, but they could be butted
and flush rivetted just as well.

This a video worth watching, as it also includes making wing to
fuselage fairings, as on low wing airplanes, but which we don't
have to worry about on the BH.

I also bought Tinman's starter kit for aluminum welding. I
haven't gotten into it yet, but I'm planning on doing an
article, for Airbum, if no place else, titled something like
Country Klutz Tries the Impossible: a Study in Learning.

Stay Tuned.

+++ #5242
From:  Jim Ash <ashcan@m...>
Subject:  Re: [Bearhawk] Re:Tinman Video

For those at the Sun 'n Fun:

Go to the hand-forming tent and spend a half hour or so with a
shot bag and some mallets and dollies. Once I got the basic
principles, I found it pretty easy to form up a part. If you're
going to work with sheet metal, this skill is a must-have, as
well as being a lot of fun.

+++ #5667
From:  WAYNE ESTMENT <estlec@m...>
Subject:  LASER CUTTING

Does anybody know if laser cutting 2024 T 3 sheet will cause any
cahnges in amterial strength due to the heat of the laser.

Wayne

+++ #5668
From:  hkeil@n...
Subject:  RE: [Bearhawk] LASER CUTTING

there will be a heat affected zone along the cut.  It will
probably not be too wide in thin sheet.  Have you considered
water jet cutting?  No heat affected zone, easier to deburr, you
can stack the sheets up to one inch thick for ribs and such.
Herman Keil (lurker)

+++ #6229
From:  Russ and Penny Erb <erbman@p...>
Subject:  RE: [Bearhawk] air compressor

Compressor: Depends on your tools.  Rivet guns won't stress it,
and air drills aren't that bad.  Check flow rates on spray guns
and sandblasters.

+++ #6235
From:  Budd Davisson <buddairbum@h...>
Subject:  Re: [Bearhawk] air compressor

Air compressors: sand blasters are the real air-eaters. Ditto
cut off wheels.  Figure a mininum of 5 horsepower, 30 gallon
tank, 7 cfm at 90 psi. 7 hp, 40 gallon is better. $500 will buy
more air compressor than you can use. it'll be 220 AC, by the
way.

bd

+++ #6236
From:  Bob Romanko <romanko@v...>
Subject:  RE: [Bearhawk] air compressor

Here is a response I made to someone thinking that only a
2-stage compressor would work for aircraft construction.  I
posted it on RAH:

A 2-stage compressor required for aircraft  building?

This is pure Barbra Streisand (BS).  A single-stage compressor
will do you just fine assuming you buy a big enough
single-stage.  I have a Porter-Cable that is a 220V motor on a
60 gallon vertical tank.  It's right around 9.6 CFM at 90 psi.
That keeps up nicely with a 4000 rpm drill motor, and dies of
boredom with anything else I have.  Harbor Freight now sells
several compressors with close to the same specs for less than
$450 USD and free shipping in the continental US.  I paid $410
for my Porter-Cable, and have been totally thrilled with it.
With these larger single-stage compressors you're talking
belt-driven, twin cylinders.  DO NOT GET A DIRECT DRIVE
"OIL-FREE" COMPRESSOR!  If you think I'm shouting, wait until
you plug one of those babies in.  If in a confined space, quite
possibly the loudest sound you'll ever hear.

For what it's worth...

Planter Bob

+++ #6239
From:  meldredge@a...
Subject:  Re: air compressor

> you're talking belt-driven, twin cylinders.  DO NOT GET A
> DIRECT DRIVE "OIL-FREE" COMPRESSOR!  If you think I'm
> shouting, wait until you plug one of those babies in.  If in a
> confined space, quite possibly the loudest sound you'll ever
> hear.

what?  WHAT?? DID YOU SAY SOMETHING??? MY DIRECT DRIVE OIL-FREE
COMPRESSOR IN THE BACK CORNER OF MY GARAGE JUST KICKED ON.

Yes, it's $#(*& loud.  I have to remember to shut it off at
night just so it doesn't pick an inopportune time to re-fill
itself and wake the neighborhood.  It was inexpensive, though.
$230 or so at Sam's Club

-Mike (wearin' ear plugs) Eldredge #427

+++ #6245
From:  Ken Beanlands <kbeanlan@s...>
Subject:  Re: [Bearhawk] Re: air compressor

The other two disadvantages that were brought to my attention
(may or may not be true) were that the oil-less compressors will
eventually wear out thier bearings (usually some sort of
synthetic material) and will need replacing. If the company is
out of business, you may have a disposible compressor. Granted,
with the amount of use that we amateurs give it, it would
probably last our lifetimes. With proper maintenance, the oil
type last a lot longer.

The other thing was that the belt drive compressors can be
replaced in a modular fashion should something fail. Say, for
instance, the pump failed. You could truck down to your local
compressor repair shop and buy a refurbished pump from another
vendor, make up some mounts for your tank to accomadate the new
pump and slap on a new belt and pulley to fit and away you
go. Same goes for the motor and for the tank. With direct drive
units, you are far more dependant on finding exactly the right
motor and pump as they are bolted together as one unit.

However, as Mike pointed out, you can generally get 2 Direct
Drive Oil-Free compressors for the cost of one oiled, belt drive
one.

One other thing that was suggested was to look for a compressor
with a cast iron head rather than aluminum as it disipates heat
better and is less prone to fatigue cracking.

I ended up with a Campbell Hausfel (sp?) 4.5 HP belt driven,
oiled, iron headed compressor for about $450 CAD ($300
USD). It's OK for most things but a little small for an HVLP
spray gun. I've been using it anyway but I might try and get a
bigger, or just a second compressor for the wings.

BTW, can anyone see any problem in hooking up two compressors in
parrellel to try and get enough flow to spray the plane? I'm
sure I can find someone else in the area that will need to spray
a plane that I can work out a deal with. (I borrow his and he
borrows mine)

Just some food for thought.

Ken Beanlands B.Eng (Aerospace)

+++ #6247
From:  zipppydoggg@y...
Subject:  Re: air compressor

> With proper maintenance, the oil type last a lot longer.
> 
> I ended up with a Campbell Hausfel (sp?) 4.5 HP belt driven,
> oiled, iron headed compressor for about $450 CAD ($300
> USD). It's OK for most things but a little small for an HVLP
> spray gun. I've been using it anyway but I might try and get a
> bigger, or just a second compressor for the wings.
> 
> BTW, can anyone see any problem in hooking up two compressors
> in parrellel to try and get enough flow to spray the plane?
> I'm sure I can find someone else in the area that will need to
> spray a plane that I can work out a deal with. (I borrow his
> and he borrows mine)

I have an old (20 years) craftsman 2 horse with 20 gal tank
(iron head, belt drive, etc.).  It is OK, and has lasted a long
time. It is not big enough for large sandblast jobs, but can
generally keep up with a conventional spray gun. One thing I did
is add an automotive air filter to keep the grip out
(sandblasting) and replaced the air line from the compressor to
the tank with a long length of copper tubeing, made into a coil,
to reduce the temperature of the air going into the tank.  I
don't really care what temperature the tank is, but the
unloading valve is mounted at the tank, and was getting
overheated (causeing sticking) with the short stock length tube.

All that said, I think there is a bette