>>> 2mar02 #7686-9153 +++ #7708 From: Russ and Penny Erb Subject: Bring back the Draft! HA! You thought this was something about national military policy--but no! It has been widely published that 4130 should be welded in absolutely still air because it is an air-hardening alloy. Some have gone so far as to suggest that the welder refrain from breathing or moving as that would cause too much of a draft. My question for the self-styled metallurgists out there (or even classically trained metallurgists): At what temperature is the draft-dodging no longer an issue? Is it only an issue while the steel is glowing red? Is it an issue when warm to the touch? I feel confident it's not a problem at one degree above room temperature, but I also think the cutoff temperature is higher than that. The real question is how long do I have to wait after welding before I can turn the shop fans back on? Russ "Not a licensed metallurgist, and doesn't play one on TV" Erb #164, Edwards CA +++ #7710 From: charles.eyanson@u... Subject: Re: Bring back the Draft! Some thoughts from an amateur blacksmith and armchair metallurgist: The steel is susceptible to hardening while it is still austenitic (essentially red hot and non-magnetic). Once its magnetic properties return it won't harden (at least not enough to notice). But that isn't the only consideration. Depending on cross section, steel can be susceptible to cracking or warping at any temperature that it will turn water to steam. It shouldn't need saying, but since you are an engineer I'll warn you not to use water to test the temp or you will get cracks and warps ;-) Cooler than that should be okay. I hope this was helpful. Chad Bearhawk 397 One Design 00-443 +++ #7712 From: "Bruce A. Frank" Subject: Re: Bring back the Draft! Once 4130 drops below about 400 degrees F there is little metallurgical change happening upon which circulating air will have an impact. From there on down to low ambient the steel's characteristics stay about the same. Going really cold (a dip in liquid nitrogen) brings about some additional permanent changes to the characteristics of the steel, but that seems an unlikely treatment of one's fuselage. 8^) My rule of thumb is to wait until I can touch the welded area. Not hold my hand on it, but no burns happen in that split second of contact. Experience has shown that that temp is just a little above 200 degrees F. Then, at that temp, I may even dip a part in water to facilitate handling. Now for the "experience" story. I have acetylene welded 4130 tube samples when my hangar temps were 20 degrees F (winter time late nights in PA) and allowed to air cool. When I tensile tested those against samples welded and cooled at 70 degrees F ambient I found no difference in either elastic deformation, inelastic deformation, yield or tensile failure. (testing done at a certified lab in Wilmington DE) Air hardening doesn't necessarily mean embrittlement. On really thin sections I can see air induced cooling that could happen fast enough to affect the hardness of the steel, but on .035" and thicker, unless you have a really brisk breeze from your fan blowing directly on the part it can't give up its heat fast enough to embrittle. Another rule of thumb that has proven OK for me is that if the air movement is not enough to cause problems with the welding process there seems to be no harm caused in the cooling taking place after welding. Bruce A. Frank +++ #7714 From: Budd Davisson Subject: Re: Re: Bring back the Draft! Yet another opinion: The air-quenching effect of a draft is minor unless you're working in a full blown frigid gale. The biggest problem in a draft is that it raises hell with the welding process by screwing with the flame. If necessary, keep the draft going to stay cool, but erect a deflector around the area being welded to keep the flame stable. NOW FOR ANOTHER QUESTION FOR YOU WELDERS OUT THERE: I'm trying to do overhead welds with MIG and am having a helluva time. What's the secret? Turn the feed rate down or what? I keep getting crap in the nozzle and frying the little wire feed collets. bd +++ #7715 From: "Joe Hemmer" Subject: Re: Re: Bring back the Draft! Budd, if you are not already doing this, try weaving the gun, stroking it fore and aft along the weld to spread the heat for overhead welds. Generally keep the feed rate normal. As a last resort turn the current down slightly. As a side note, without post-weld softening with a propane torch, I am extremely unhappy with MIG welds on any quenchable steel. I understated that; the depth of my unhappiness is difficult to express. Good luck with the upside down work; or you could do like the rest of us and put it on a spindle to rotate into position for comfortable, pleasant, easy, right-side-up welding. Joe Hemmer +++ #7716 From: Budd Davisson Subject: Re: Re: Bring back the Draft! Done all the suggestions and still can't make it work. Can't rotate it as it is the bottom of a car frame. So, I dragged the old buzz box out to practice the weld and ran a perfect bead first time. This is nothing short of a miracle for me. As for post head, pre-heat and all that. Most on the group know my feelings about all of that with MIG and 4130. MIG has its place but not without some serious pre-cautions, when it comes to high carbon steels. Of course, American Champion and Maule both MIG and don't stress relief. Go figure. But then, who wants to use them a models of how to build airplanes. bd +++ #7717 From: "Joe Hemmer" Subject: Re: Re: Bring back the Draft! Budd, only one more thing I can think of: smaller diameter feed wire? Joe +++ #7718 From: zipppydoggg@y... Subject: Re: Bring back the Draft! I was thinking of post-weld heat treating the clusters, because the longerons will be "sucked in" by the cluster welds. I would suppose that the final cooling sets the metal properties, not the intermediate welding. I plan to heat with propane, weed burner on gas BBQ bottle. On a no-wind day, it should be OK. Just a thought. Rob "actually say the top of my work bench this weekend" Gaddy BH401 +++ #7719 From: Jimmy Mathis Subject: Re: Re: Bring back the Draft! You may try turning the feed rate down and if that isn't enough, try lowering the heat a notch. I've also noticed that when I'm welding overhead, I tend not to move the weld along as fast as when in an easy position. Try using a prop under you arms to stady the weld. Jimmy 501 +++ #7720 From: "dean robert cramb" Subject: bring back the draft When I post heat the weld I always wrap the joint in a fiberglass blanket. This lets the weld cool down slow and evenly. Don't know if this is all that important, but it works for me... +++ #7721 From: "Bruce A. Frank" Subject: Overhead MIG Welding Overhead MIG is difficult to accomplish with a good looking end result. First everything needs to be clean, sand or bead blasted. If it is a lap joint and the frame material is 1/8 inch or more the method, contrary to what many think, is to run fairly hot and move quickly. Use an exaggerated "U" weave. .035 wire will work well. It may actually be more difficult with .023". Use a new contactor tip and anti-spatter. Bruce A. Frank +++ #7722 From: "doug" Subject: Re: Overhead MIG Welding I disagree on the "U" weave pattern. The only time I use a "U" weave is on a key-hole root pass. Every thing else is an "e" with the fresh swath being the vertical segment. And this is pushing the weld and NOT DRAGGING it. Budd, heat travels upwards and turning the heat down a little helps. there is a fine line on works and what doesn't. Change only one parameter at a time until you fully understand overhead MIG. The real trick is to learn HOT and turn it down as needed. If your weld is falling out on you try welding a litter faster. To much spatter is too much heat, and jerking spatter is too much wire speed. There is a optima on what you want and takes only a minute to figure it out, But I'm not there. Try having someone adjust the wire speed while you are welding, that may really help too. Doug #433 certified 3G & 4G in both GMAW & SMAW +++ #7723 From: "Bruce A. Frank" Subject: Re: Re: Overhead MIG Welding >Every thing else is an "e" with the fresh >swath being the vertical segment. With MIG? What gas? With MIG because of the continuous feeding of the wire it is always requires effort to prevent a ropy high center. I am not familiar with the "e" movement as you describe it. It sounds that you actually make your procession movement with the middle leg of an "e" shape? Why isn't there excessive deposition in the center of the fillet? Though I no longer carry certs in pipe 'cause I don't do that any more, if we are showing our training mark me 6G SMAW, GMAW, and GTAW. Bruce A. Frank +++ #7724 From: Budd Davisson Subject: Re: Overhead MIG Welding Thanks. Now at least I know it wasn't me. I have, however, discovered I can stick weld much better upside down than rightside up. Must have something to do with flying a Pitts so much. bd +++ #7725 From: "Bruce A. Frank" Subject: Re: Overhead MIG Welding Stick electrode welding is a neglected art these days. Many people don't realize how useful it is or how many things can be welded easily with stick whereas some more "modern" methods are difficult to apply. Most notable is the ability for one to "get away with" welding painted or rusty steel with stick. Doug at Metalfab disagrees with my method, but I do agree with him that each situation requires adapting one's technique. I have never found anyone I couldn't teach to weld, but many whom I have taught quickly exceed my skill sometimes doing things entirely differently than I do it. Bruce +++ #7726 From: "doug" Subject: Re: Overhead MIG Welding Set yourself up for a simple fillet, say about four inches long. Either working left or right handed, trigger and begin your weld. At the bottom edge of the fillet move forward into the root and then slight back and up to the top edge of the fillet. At this point you have made the first half of the "e". The next step of the "e" is to wash back over the top in a downward motion and begin the next "e" in the forward direction in the root. What you are trying to do is do a very small vertical up weld in the distance of the bottom edge to the top edge of the fillet. This gives the best bead profile and penetration. The wrong way to do this is to the down hand segment into the root and the uphand segment over the top of the weld and we call these welds "l". I use C25, and years ago used CO2. C25 is cleaner, but both will give the same results, gas has nothing to do with it. Volt setting will be different and you have to know and allow for this. Doug #433 +++ #7853 From: Russ and Penny Erb Subject: Pop! Goes The Regulator As I was setting up to start welding today, my acetylene regulator was "popping". That is, the pressure was fluctuating rapidly, from once to twice a second. It had done this before and then stopped, but this time I couldn't get it to stop. It was as though the regulator mechanism was sticking, building up pressure, releasing, sticking again, etc. Imagine how tricky it is to weld with the flame pulsating. "Puddle Control" is basically impossible. I fixed the regulator by replacing it with a new one. The old one was about 5 years old. Have any of you had (or heard of) a similar problem? Anyone have a good explanation of the problem? Is there any way to fix it other than replacement? Russ Erb +++ #7854 From: "Bruce A. Frank" Subject: Re: Pop! Goes The Regulator Trash (particles of metal, dirt, spider bodies...) can cause this type of malfunction. Normal wear on the diaphragm can cause this type of malfunction. The regulator can be overhauled easily by a welding repair shop; usually one to four weeks. If it is an inexpensive regulator ($80 or less) replacing is the easiest thing to do. Many welding supply shops will also have rebuilt regulators for sale for very good prices. It is also possible to disassemble a regulator and clean it and/or replace the diaphragm yourself. It is not difficult, the mechanism is simple, all it takes is a vise and a large adjustable or sometimes a strap wrench. A procedure one should follow religiously is to always, before installing the regulator on a new cylinder, point the cylinder valve in a safe direction (not at your face) and crack the valve for a split second. This will blow away any trash in the valve nozzle so that it doesn't get forced into the regulator. Lot of people don't want to waste that split second of gas. Now there is one other thing that can cause such fluctuations in pressures in an acetylene cylinder. If the refiller has overfilled with acetone the cylinder may spit a little acetone through the regulator and cause these problems. A cylinder that has been transported on its side may sometimes have a slug of acetone in the neck of the valve which fowls up the regulator for the first few minutes of operation...usually clears up in a minute or two. If the cylinder is allowed to sit upright for a few minutes before opening the valve the acetone will have time to drain back into the body of the cylinder. But, if the new regulator solved the problem it is most likely that the regulator was the problem. Unlike airplane builders few people oxy/acet weld these days. Regulators are made much more cheaply than those produced 40-50 years ago. It is very difficult to find two stage regulators, which provided absolutely uniform pressures to the torch regardless of the cylinder pressure, in the market today. Most regulators available today have to be adjusted upward as the gas is used and cylinder pressure drops. Bruce A. Frank +++ #7857 From: egregvana@a... Subject: Re: Pop! Goes The Regulator they make a repair kit for regulators consiting of a diaphram, springs, and valve seats. thet are inexpensive and simple to install. note, use no lubricants when assembling, and check the inflow screen for obstructions, and also make shure all parts move freely without any binding.-------greg vana +++ #7859 From: "Kent White" Subject: RE: Pop! Goes The Regulator I used to rebuild all my regulators myself, until my welding supply house was forbidden to sell the kits to "private citizens", a few years back. When the regulator goes goofy for any reason, I just replace it. Sorry, but the economics of throwaway are way too prevalent, and it is a losing fight for true rebuildable quality any more. IF you can get a rebuild kit, it is really easy to unscrew the faceplate (with the regulating screw in it) from the body, and pull out the thrust washer, spring, and diaphragm. Clean and inspect all openings for debris and reassemble using the new parts, with no oil or grease on any internal parts at all. In the old days there was a smidgen of light grease on the thrust washer for the adjusting screw to turn against, easing the friction there. Spitting is a different phenomenon, with the torch flame periodically jetting out in yellow-white spurts. This is due to a superabundance of liquid fuel (acetone) in the cylinder, caused by someone overfilling the bottle. Either return it, or upend it and look for the little drain plug on the bottom....... Kent White ...sure love that Bearhawk CD..... +++ #7860 From: Tim Hickey Subject: RE: Pop! Goes The Regulator > Spitting is a different phenomenon, with the torch flame > periodically jetting out in yellow-white spurts. This is due > to a superabundance of liquid fuel (acetone) in the cylinder, > caused by someone overfilling the bottle. > > Either return it, or upend it and look for the little drain > plug on the bottom....... > >Kent W I have to ask: What are you intending to do once you find that "little drain plug"? I hope no one intends to remove it and to try and "drain" any excess acetone. What a mess that would be. DO NOT REMOVE THE PLUG! When I was in the Army, 69-71, I was an Oxygen/Acetylene Generation Specialist. Our job was to fill cylinders with the above products. Separate and different cylinders, of course. Acetylene is actually stored in the acetone in a manner that CO2 is stored in Pepsi. In addition the inside of the cylinder is filled with a sponge like material that serves to "soak up" the acetone. Storing acetylene as a gas under pressure can be very dangerous. Locally we had two guys killed about a year or two ago when they were trying to use a compressor to pump acetylene into containers to use as power for paint ball guns. It is possible to overfill a cylinder with acetone, and this will cause some of the liquid to be carried out with the gas when used. I should note that acetylene cylinders should always be used (and chained) in an upright position. And make damn sure that you turn the tank off at the end of use. You have no idea what can happen to a garage that fills up with leaking acetylene over night when the torch valve was cracked open. Don't fool with the cylinder. If you think you have a defective one for any reason, contact your supplier. Tim Hickey +++ #7862 From: "Bruce A. Frank" Subject: RE: Pop! Goes The Regulator > I have to ask: What are you intending to do once you find that > "little drain plug"? Amen! Bruce A. Frank +++ #7889 From: "Owen Davies" Subject: Burns > RE: [Bearhawk] Erbman's wing takes a ride No doubt I've said this here before, but so few people seem to pay attention that frustration forces me to repeat: Whenever you get a burn, slather it with the oil from a vitamin E capsule. (The oil you get in a bottle is not nearly as concentrated.) In an hour, you'll never know it happened. The sooner you get to it the better, but it's still worth doing even two hours later. My wife once put her hand on an electric stove burner set to high and red-hot. It should have left scars. That one took two hours to become free of pain, but a couple of days later there was no sign of it except for some dry, dead skin, still well attached to healthy tissue underneath. Owen Davies +++ #7890 From: "vic" <11acs@g...> Subject: Re: Burns Aloe Vera gel is much better. +++ #7892 From: Budd Davisson Subject: Re: Burns I have what we call the Smith Plant around here. When I'm standing there with my Smith torch in one hand and a burn in the other, I whack a leaf off the plant, skin the surface off and rub the gel into the burn. MAJOR EFFECT! I've spent 45 years perfecting new and painful ways to burn myself while welding and the old aloe plant is the best fix I've found...next to remembering what's hot and what's not. Thank God my redhead is in charge of watering the plant. bd PS remind me to tell you how I managed to burn two fingernails off while teaching myself how to apply body lead. I was 15 at the time and it still hurts to think about it. +++ #7904 From: charles.k.scott@d... Subject: Re: Digest Number 577 > One burn that I have repeated on several occassions is > sticking the red hot end of the rod into my belly. Last year I bought a leather welding smock that I now wear whenever I weld. Works nicely when grinding too. Corky Scott +++ #7910 From: "Kent White" Subject: RE: Osama off topic PS: vinegar, then aloe for burns. Vinegar reduces the pain and is handy right away, and gives you time to get to the aloe which is usually in the fridge or in the flower pot some distance away. For severe steam burns on the hand I have worn a rubber glove filled with iced vinegar for 8 hrs. When the pain dropped I changed to aloe. No scars, no infection. Long successful history with this treatment for powder burns and hot steel and molten aluminum. Sooner is better than later with burn treatments. Sorry about mentioning the valve on the bottom of the acet. I am familiar with such things, and mistakenly assumed others were, too. kw +++ #8097 From: Russ and Penny Erb Subject: Ventilated Welding Goggles, or Erbman is a Hothead Has anyone heard of welding goggles with forced air ventilation? My problem is that I wear prescription glasses under the goggles and it gets warm enough that I start sweating just enough to fog the glasses. Makes it tough to weld in a fog bank. I'm pretty confident that I'm not the first one to have this problem. Have any of you sight-challenged welders had this problem or do you know someone who did? What was your/their solution? It's very annoying to finally get a good bead going and have to stop because I'm suddenly welding on a London morning. Russ Erb +++ #8098 From: "Sharon Theiss" Subject: Re: Ventilated Welding Goggles, or Erbman is a Hothead My son, while taking a welding class at the local tech school, had the same problem. I got a pair of 12VDC CPU cooling fans from Radio Shack and mounted them in each side of his helmet. Get the small ones and run them at reduced voltage from a "D" cell battery box attached to your belt. One intake, one exhaust for a welding helmet, one intake and vented exhaust for goggles. Helps to have the large size goggles. Be careful of drying your eyes out with too much flow. Sort of like riding your motorcycle but without the bugs. You could baffle them with tape to adjust the amount of airflow, no worry, the less airflow, the less load on the motors. Now let me tell you about the teeny-weeny windshield wipers I ------- ;>) Scott Theiss Lake Lure, NC Plans #499 +++ #8099 From: lglenn4@e... Subject: Re: Ventilated Welding Goggles, or Erbman is a Hothead I would suggest you get a cheater lense for your goggles from your welding supply so you don't need to wear glasses. Roy # 274 +++ #8100 From: Russ and Penny Erb Subject: RE: Re: Ventilated Welding Goggles, or Erbman is a Hothead > I would suggest you get a cheater lense for your goggles from > your welding supply so you don't need to wear glasses. Roy # 274< A good idea, but they don't make goggle lenses in +5 diopters...at least not that I know of... Anyone know of an outfit that makes prescription lenses for goggles? Russ Erb #164, Edwards CA +++ #8101 From: "Joe Hemmer" Subject: RE: Re: Ventilated Welding Goggles, or Erbman is a Hothead Russ, there is a guy called "Erbman" who is very facile with epoxy and drugstore "reading glasses". He might need a pair of +3 and +2 diopters to get the focal distance correct. Biggest lenses you can find, that still fit inside the goggles. See if you can talk him into cutting up a couple pair of the drugstore glasses and gluing them into your goggles, with appropriate wooden or foam spacers. Joe Hemmer Davis, CA +++ #8102 From: "Bruce A. Frank" Subject: Re: Re: Ventilated Welding Goggles, or Erbman is a Hothead "Cheater" lenses don't let you see better if you need corrective lenses. All they do is magnify. You use them with your regular lenses so that you don't have to try to align the bi-focal of your prescription glasses to see the weld. What I did originally was to take an old arc welding hood and mount the #5 shade acetylene lens in it. The hood allowed free circulation of air so the fog didn't develop. Later, and I don't know if they still make it, Jackson made a light weight face mask that looked like a scaled down arc hood designed specifically for the acetylene process. I say I am not sure it is still made because there were several cases of idiots deciding they liked the light-weight-ness of the acetylene hood and installed a #12 to arc weld with it. Since it was smaller and didn't protect they received sever arc burns, just the product liability thing that gets good ideas removed from the market. Bruce A. Frank +++ #8103 From: "Bruce A. Frank" Subject: RE: Re: Ventilated Welding Goggles, or Erbman is a Hothead Actually you should be able to get prescription lenses to fit your acetylene goggles made at most any place like Pearl Optical or Lens Crafters. I have had several similar lenses made for my scuba goggles...the lens would be like the magnifying lenses (cheaters) placed in the acetylene goggles behind the dark lens. Bruce +++ #8104 From: rsmith@a Subject: Re: Ventilated Welding Goggles, or Erbman is a Hothead Go to a welding supply store and buy a #5 shade face shield. Fits the same headband as the clear face shields but is slightly thicker. Cost me $15 locally. No problem wearing glasses underneath and I like it way better than goggles. Protects your entire face from heat and sparks. Rod Smith #246 +++ #8105 From: Budd Davisson Subject: Re: Re: Ventilated Welding Goggles, or Erbman is a Hothead I usually weld wearing two pair of glasses, 150 and 400, at the same time. I'm using the kind of goggles that flip up and they have vents on the sides. I sweat so much out here sometimes that I have to make sure I dn't hurt a weld by sweating on it and I've never had my goggles fog up. Gheeze, Russ, it must be your eyeballs sweating. Maybe you just need to relax, think soothing thoughts, or fill your pockets with icecubes. And Rod is right about the face shield. bd +++ #8106 From: Jerry Russell Subject: Re: Ventilated Welding Goggles, or Erbman is a Hothead Russ, I use my SpeedGlass Automatic welding hood to gas weld I just don't turn it on. gives me a lot of breathing room. The also make one that is forced air fed if you need a lot of ventilation. If thats not a solution you can get perscription welding goggles. Jerry Russell +++ #8107 From: supermexgarza@a Subject: Re: Ventilated Welding Goggles, or Erbman is a Hothead just a face shield with the proper shade will do a welding hood is some what heavy, and restricts the field of view, the darken face shield and i are good buds this subject is a sore spot growing up in a welding shop and wearing glasses since 4th grade i have welded just about any thing and those fogged glasses are the most annoying thing Im getting that feeling just typing about it turning your face to look thru the little spot on the corner of the glasses that is not fogged Javer Garza +++ #8108 From: Ken Beanlands Subject: Re: Ventilated Welding Goggles, or Erbman is a Hothead Depending on the nature of your "sight challenge" it might be possible to weld with your glasses off. I'm near-sighted and have no problem with taking off the glasses when I weld. Another possibility might be to use the disposable contact lenses when you weld. I had exactly the same problem when I went skiing. Whenever I stopped on the slopes, the glasses fogged up. So, I started using these disposable contacts and it's worked great. I pop them in while I gear up in the parking lot and toss them out when I hit the bar after the skiing is done. It costs about $3.00 per day (compared to the $60 for the lift pass, it's pretty cheap). Ken Beanlands B.Eng (Aerospace) +++ #8137 From: Jerry Russell Subject: welding I just unloaded my new Miller 250 DX Squarewave welder off the truck last night and am waiting on the optional features to be shipped, pulaer, sequencer and power-factor correction. While I'm in the down mode does anyone use this rig or similar and if so what are your settings for Chrome Moly. Jerry Russell +++ #8225 From: Russ and Penny Erb Subject: Welding Rod Thoughts This first idea is obvious, i.e. a "Well, duh!", but the most obvious idea is useless if you don't think of it... If you're like me, after a big welding job (like a fuselage), you have pieces of welding rod about 6 to 10 inches long strewn around all over the floor. These are the cast-offs from when the rod gets too short to hold without your hand getting rather warm. And if you're also like me, you're getting old enough that bending over a lot starts to make your back hurt. Therefore, what's the best way to pick up all (most) of those rod pieces? I tied a magnet to a cord and used that to pick up the rods dregs. You could use a broom as well, but that picks up a bunch of other stuff too. Why am I picking them up? They represent about 25% of the welding rod that I bought, and there's no reason to throw it out when it's still good. I put the itty-bitty tip on the torch and weld them back together into longer rods. For those who haven't thought about it, I've been using primarily 1/16" rods for most of the welding. I've also used a fair amount of 3/32" rod which is good for providing filler material to fill gaps and fill those holes that invariably show up in the tubes next to the welds. Russ Erb +++ #8226 From: "Tony Chisum" Subject: Re: Welding Rod Thoughts Try this, While you are welding. When the rod gets to short to hold stick it to what you are welding, then get another rod and weld it to the stub. Then go back to welding. That way you use all the rod with on waste. +++ #8227 From: bearhawker@a Subject: Re: Welding Rod Thoughts A little technique for taking care of those rod nubs is to simply tack weld them onto your next rod. Lay the two rods, end to end on a firebrick or whatever you use as a welding bench, hit it with the torch and voila! One really long welding rod with a minor growth on it where the two rods were pushed together. Only takes a sec. ##Carl#Turner#328 +++ #8466 From: "Chris Vuxton" Subject: OT: Welding a quarter to 4130 This may seem like a silly idea but does anybody know how to weld a new US quarter to a piece of 4130? I thought it would be fitting to weld one of the new NC quarters with the Wright Brothers side facing out into the cabin. Braze, Tig, what? Chris +++ #8467 From: "Ron Webb" Subject: Re: OT: Welding a quarter to 4130 Solder? +++ #8468 From: "Tony Snow" Subject: Re: OT: Welding a quarter to 4130 JB Weld! No heat - no damage to structure... Tony +++ #8469 From: "bearhawk0312" Subject: Re: OT: Welding a quarter to 4130 For what you are asking it to do, NOT needing any structural strength and wanting to keep it in great condition without any distortion. I would use JB Weld, it is a two part epoxy and can be found at most hardware stores. Doug +++ #8500 From: BruceAFrank@a Subject: Wright Quarter Attachment The JB Weld is probably the best choice, but I played around with it some and found that low temp silver solder with a soldering works well. Sanded the 4130 bright, applied a little Harris flux then placed the iron against the face of the coin while feeding solder to the contact area between the coin and the 4130. Was able to solder it to both a flat piece and a tube with this method. The silver solder was strong enough to require real effort to break the coin off the tube. Also tried soldering the coin standing edge ways on a tube. Worked, but was easily knocked off with a hard bump with my hand. Bruce A. Frank +++ #8555 From: Russ and Penny Erb Subject: Boiling Weld Puddles (Hopefully this won't panic anybody...) Just thought y'all would like to know...recently on occasion my weld puddles would look like they were foaming or boiling instead of melting normally. It took me a while to figure out why. I first thought it was contamination (soot, grinding dust, whatever) on the weld rod or tubes. Turns out it was excess oxygen in the weld flame. Sometimes the gas flow doesn't stay where you set it, but drifts a little. In this case, it had drifted to a little excess oxygen. The weld puddle metal was burning (oxidizing) creating the foam. Once I figured this out, I haven't had the problem since. This is why if your flame isn't exactly neutral, it's better to have slight excess acetylene (slight feather in the flame). I'm sure many of you knew that already, but it's always good to bring it up for those who didn't. Russ Erb +++ #8558 From: charles.k.scott@d... Subject: Re: Digest Number 655 > Turns out it was excess oxygen in the weld flame. That is exactly why you are supposed to set your flame to neutral with a little tiny feather you can see. The little feather tells you where the flame is set. If you don't see the feather you should stop working and adjust the flame again. It's the only way to be sure how the flame is adjusted. The flame does change over time. Heat appears to change things and maybe there's excessive pressure in the line that does not bleed out right away which will change the flame. Corky Scott +++ #8561 From: "Bruce A. Frank" Subject: Re: Digest Number 655 > That is exactly why you are supposed to set your flame to > neutral with a little tiny feather you can see. Part of the problem these days is the type of regulator that is commonly available. Back in the days when people actually welded with oxy/acet the regulators were what was called a two stage. Gasses were metered very carefully over the pressure range of the cylinder so that the output side of the regulator hardly varied at all. Even the most expensive regulators these days are aimed at oxy/acet cutting rather than welding. Two stage regulators are available these days, I bought a pair about 8 years ago. I have a Smith jeweler's torch with two stage regulators that is almost 70 years old that my father used to make instrument repairs. The regulators hold perfect adjustment even when cylinder pressures change 1000 psig during one welding session (small portable cylinders). The newer Victor regulators have to be re-adjusted when cylinder pressures change as little as 50 psig. Bruce A. Frank +++ #8592 From: Budd Davisson Subject: Re: Boiling Weld Puddles An absolute, never-to-be-broken rule of welding: the puddle should always be tranquil, like a drop of onion soup sometimes with just a hint of cheese (sloss) floating on the top. If there is any activity within the puddle at all, especially at the levels you mention, the weld is extremely brittle and thoroughly oxidized. The color and tranquility of the puddle tell you if the flame is too lean without even looking. See Zen and the Art of the Weld Puddle, www.airbum.com. bd +++ #9024 From: pfflyerz@c... Subject: poppng rosebud I need some advice from the welders in the group on how to set up my rosebud torch. My fuselage is now done. I hope to begin sandblasting next week but first want to stress relieve the spar and gear clusters. I can't figure out what I am doing wrong with my rosebud. I left the regulator pressures the same as for welding, approximately 4 lbs acet. and 8 lbs oxy. I've got about an inch and a half feather, which seems very acetlyene rich, but any more oxy will blow it out. Even then, it will often blow out when the cluster warms up. The worst is when it pops like a machine gun, it then becomes difficult to get any kind of steady flame at all. I have two tips and they both act the same. What's up? Pat Fagan #232 Pearblossom CA +++ #9043 From: "scott anderson" Subject: Re: poppng rosebud When using a rosebud tip you need to increase the pressure of the acet. and oxygen. The acet should be around 6 or 7 lbs the oxygen around 10. What is happening is you are not generating enough gas flow to operate the rose bud tip so it is over heating and back fires in wear the gases ore mixing. The tip could also be to big for the amount your regulators are capable of flow. Remeber do not let the pressure go above 9 lbs for acet. this is the pressure wear acet self ignites. Scott +++ #9044 From: "Michael McDonald" Subject: Re: poppng rosebud I don't know you really got me confused on how you even get your torch to work at those setting's.when I went through welding school the settings were 7 acet. and 35 oxy.And have used it on job's at 10&45 .You can use a lower setting for gas welding but 7acet. & 35 oxy. should be fine as long as you use a small enough tip. Acet. become's unstable at 25lbs.and explosive at 27. Mike +++ #9045 From: "Bruce A. Frank" Subject: Re: poppng rosebud I started to post this last night and for some reason never hit the send button. ===== Clean all the holes in the tip. Turn the oxygen regulator up to at least 25 lbs and the acetylene regulator up to 10. Part of the problem with popping, particularly when in close and down in a cluster is that the head of the rosebud gets hot enough to ignite the mixture inside the torch. Part of the job of the gas flow is to cool the tip. Too low a volume allows the mixture to burn inside rather that at the surface of the tip. Too low a pressure allows ignition to flash back into the holes even when the tip is not overheating. Too low pressure combined with in close and hot can cause worse than just popping, it can cause flash-back ignition and burning (usually manifest as a squeal) inside the torch body. When welding, rather than just when post heating, sparks from the puddle can actually enter the tip and cause ignition inside and cause popping (another good reason for using a filler rod containing a high content of deoxidizers...quiets the puddle). Even in the welding situation running more volume through the torch will stop the popping. If you need a smaller flame use a smaller tip. Clean the tip regularly with good quality tip cleaners that are in good condition. ==== Another post on this subject noted dangerous acetylene maximum pressures. Most acetylene regulator gauges are red lined at 15 psig. Pressures above that can lead to spontaneous detonation. In controlled experiments detonation has been induced at pressures as low as 18 psig. Never trust the gauge (about like airplane fuel gauges) and always keep acetylene pressures below 15 psig. A very small quantity of acetylene can make a very large explosion. If you want to demonstrate this to yourself take a McDonald's large empty paper drink cup with the plastic cover on it. Light your welding torch, not the rosebud, adjust the flame, then with your gloved hand knock the flame out. Stick the tip of the still flowing torch into the hole in the cover of the cup. Five to ten seconds will fill the cup with the proper mixture of oxygen and acetylene. Take the torch away, relight it and then brush it back over the hole in the cup cover. Oh, by the way, don't do this inside a closed shop if you value your windows, have on your ear muffs, face shield and gloves. This demonstration will generate a bit more respect for acetylene than you probably have right now. Now realize that when acetylene detonates spontaneously from overpressure, no oxygen present, the energy liberation is about equal to the power demonstrated with the paper cup. If that detonation takes place in your acetylene hose it may take the regulator and top of the cylinder with it. If you are on the end of the hose holding the torch at the time you may not walk away. Bruce A. Frank +++ #9046 From: charles.k.scott@d Subject: Re: Digest Number 698 > When welding, rather than just when post heating, sparks from > the puddle can actually enter the tip and cause ignition > inside and cause popping (another good reason for using a > filler rod containing a high content of deoxidizers...quiets > the puddle). Even in the welding situation running more volume > through the torch will stop the popping. If you need a smaller > flame use a smaller tip. Clean the tip regularly with good > quality tip cleaners that are in good condition. Been there, had that. Now when I weld, I always keep a firebrick handy so I can clean off the tip. It works like this: Welding welding welding... oops, something has splattered into the tip altering the flame. You can tell this instantly because the flame is suddenly distorted and it often hisses differently. It doesn't wreck the weld but it distorts the flame so that it's difficult to do the usual pristine work you are used to. ;-) When this happens, I take the tip, with the hissing flame, to the fire brick and stick it right against the brick. It's as if I'm trying to light the brick, but you actually squash the tip right against the brick so that the flame is squeezing out sideways past the tip against the brick. Rub it around in a little circle until you hear it pop. Once it pops the material is removed and the flame looks normal again and sounds normal too. Sometimes the puddle does throw some spatter right into the tip and ignites the mixture inside the tip. This is also easy to detect because your flame usually goes out since it's now inside the tip. It also makes a distinctive scree sort of noise. This one you fix by turning off the both oxygen and acetylene, or at least that's what I do. Corky Scott +++ #9047 From: "Bruce A. Frank" Subject: Re: Digest Number 698 Rather than a brick, use a block of 2 X 4. It is easier on the tip and re-ignition of the sometimes snuffed out flame is more positive. Bruce A. Frank +++ #9049 From: Russ and Penny Erb Subject: RE: Digest Number 698 > Sometimes the puddle does throw some spatter right into the > tip and ignites the mixture inside the tip. I've had this all too frequently, which I finally figured out came from having too small a flame, thus requiring the torch to be held to close too the weld. Gets hot, then pops, followed by the screeching noise. I've found if you're reasonably quick (within about 10 seconds), you can turn off just the oxygen, then point it at the weld you were just working on, and the hot metal will relight the acetylene flame. Turn the oxygen back on and continue. I don't remember how I figured this out--I think it was by unintentional luck. Russ Erb +++ #9054 From: Leonard W Molberg Subject: Re: Digest Number 698 You all must realize that most Acetylene "rosebud" tips draw far more than the 1/7 of your bottle capacity per hour and can be very dangerous, as they tend to draw so much gas as to draw acetone from the bottle through the regulator and into the hose, where the mixture becomes unstable and explosive, especially if the oxygen pressure is enough to back some up into the gas side of the hose. A300 cu/ft acetylen bottle is marginal for even the smallest acetylene rosebud tip. Most of you seem to be using 125 cu/ft and smaller bottles and they are quite unsuitable for those kinds of gas flow. I highly recommend propane/oxygen rosebuds for this reason. I've seen the explosions. Mo +++ #9055 From: "Michael McDonald" Subject: Re: Digest Number 698 I don't really see were your bottle size will have anything to do with it. Except for the fact your going to go through a lot of bottles if your doing a lot of work with it. Something like when I had to stand over a block of steel to temper it for a long period of time. Your gas is going in one direction, and unless there is an obstruction in the tip I don't see a problem. Keeping your tip clean, proper distance from your work, along with the correct pressure setting and you shouldn't have a problem. mike +++ #9059 From: Russ and Penny Erb Subject: RE: Digest Number 698 > You all must realize that most Acetylene "rosebud" tips draw > far more than the 1/7 of your bottle capacity per hour Good point, but I've seen Pat's bottle--it's huge! I don't think he should have a problem with that... Russ Erb +++ #9060 From: Russ and Penny Erb Subject: RE: Digest Number 698 The problem is the gas can only come out of solution so fast--try to draw it out faster and it starts bringing the acetone with it. For the record, I did my "stress relieving" as I went along just heating the cluster with the tip I was using (#2 on a Henrob 2000). It may have taken longer, but since the joint was already reasonably hot, it worked well enough. Russ Erb +++ #9065 From: pfflyerz@c Subject: Re: popping rosebud Thanks for the rosebud tips, it worked much better at the higher pressure, but it is still an annoying device to work with. I still had sporadic blowouts and pops, but I managed to get done what I wanted to do. Sandblasted and primed the fuselage from the tail post to the back of the pilots door today. Will finish the job on Monday. It wasn't nearly the onerous task I was expecting, due to the pressure sand blaster. I am also oiling the tubes while rotating the fuselage for blasting. Pat Fagan +++ #9066 From: "Robert L. Thomasson" Subject: Re: popping rosebud > I still had sporadic blowouts and pops, but I managed to get > done what I wanted to do. Pat, with all the comments you got, I don't remember if anyone mentioned that holding the tip too close to the work can also cause pops? Bob >>> 4sep02 #9154-11297 +++ #9418 From: "Javier Garza" supermexgarza@... Subject: (no subject) http://www.lowbucktools.com/clamp.html this is something that a guy working with tubing could put to good use ! +++ #9419 From: Russ and Penny Erb Subject: RE: (no subject) Those look nice, and not an unreasonable price. I made up some similar clamps based on a design in the EAA Welding Handbook and they were very useful. I don't know how I would have built the fuselage without them. +++ #9918 From: Budd Davisson Subject: Re:welding help ( was Progress on #534) > There was talk earlier of 'the gift' for painting, I guess there's a > similar gift for welding. I don't seem to have it. Welding is based on four words. The first three are practice, practice, practice, but the last, which should probably be first, is "concept." Understanding the concept and what it's supposed to look like while you're practicing is what it's all about and it all happens in the first .040" of the puddle. Look at Weld Puddle, and see if that helps. +++ #9919 From: "Ron Webb" Subject: Re: Re:welding help ( was Progress on #534) I've been meaning to ask a question for a long time on this subject. When I was learning to gas weld, the end objective was a "kitfox" style airframe called a "MoHawk". Anyway, I went to the obligatory training at the local junior college, and set my shirt on fir...er...learned to weld their way. Pretty easy actually. Then I came home, bought my tanks and regulator, and all the other stuff, and started practicing on the main stuff I was going to use on the MoHawk (3/8" and 1/2" by .035 4130 tube) - Anyway, It was an awful lot harder on this tiny, thin wall tube. The edges would burn back very easily, holes would blow through, and in general, the idea of a "weld puddle" was ridiculous. If you actually got a "puddle" you had a hole very soon thereafter. You are going to say I had too big a torch, or too much heat. Don't think so. I tried lots of things, but if I had enough heat to melt it, I burned holes. I can weld .049 by 1" tube as well as anyone, but I had to resort to some funny things to make the little stuff work. I called a friend who is an expert welder, and had him try. He tried several times, then finally presented me with a butt joint that looked OK. I hit it with a hammer and it broke. One side was a cold joint, and it came right apart. My question is - Was I doing something wrong, or is this tiny stuff a pain for everyone?? +++ #9920 From: Budd Davisson Subject: Re: Re:welding help ( was Progress on #534) The size of the tubing makes no difference until you get down to .028 wall x 3/8" and even then it's not that hard. The problem is you have to recognize when you're using too much heat, which can be either in the setting of the tip you're using or you're simply using too much tip. All airplanes are made primarily of .035 and 1/2 and 3/8 isn't that uncommon. It just takes a little more attention to detail. and yes, there definitely is a puddle with any thickness of material. If you're having problems burning through or not having a puddle develop, you're using too much tip/heat and haven't developed a feeling for what the metal and puddle are supposed to look like both in color and texture. Using the right combination of tip/heat, 3/8 tubing welds the same as 1" tubing. Picking the combination is a matter, again, of recognizing when it's heating up and losing color too quickly. Doing small stuff is actually easier than the really big, heavy stuff because the torches we all use run out of heat and you need supplimental heat sources on the monster stuff. All welding is a matter of controlling the heat and recognizing when there's too much or too little, which will change constantly even within a single joint. +++ #9924 From: "fly_it_slow" "Joa" Subject: Re:welding help ( was Progress on #534) I just started learning how to gas weld with my new Henrob 2000 and boy I gotta say that this torch makes it pretty darn easy. I'm totally amazed at the control you can get with the different tips. Even with one tip it's surprising how much difference to the puddle a little adjustment makes, you can really "fine tune" it (all the time keeping the gas set at 4psi). I've been practicing on .049 tubing with slots cut down the length. Now I'm working on T-Joints and going to do sleeves and rosettes next. Then it will be on to a little thinner tubing which I'm sure will be a lot harder though this torch is very soft and unless you set it too high doesn't seem to easily blow through. I'll second the practice practice practice stuff since my welds slowly keep getting better. The part about the puddle is key too since when I first started I wasn't getting the weld hot enough and it wasn't penetrating completely through (you could see it on the backside of the weld plus the front looked like a bumpy "ridge" rather than smooth "waves"). Pretty soon I got the hang of what to look for (basically for me it's setting the heat to *just* before the point where the puddle melts completely through and you can see the surface tension wanting to create a hole, you get kind of a "dimple" in the puddle it seems). Just a little endorsement since I'm jazzed to learn something new :) BTW I don't have any affiliation with Henrob, just very satisfied :) +++ #9925 From: Budd Davisson Subject: Re: O/A WELDING EQUIPMENT If you're going oxy/acetlyene, you only have two choices, the Airline and the micro from Kent White. Anything else is too big and the adjustment knobs are on the wrong end. I'm sorry to say that we've had some really bad problems with newer Airline torches in that they won't hold the settings, when new. After a bunch of cleaning and futzing with them, they ifnally calmed down, but they are no where nearly as reliable or as smooth as the old ones. Still, they are the best game in town for the amateur airplane welder. The Micro is a good alternative but some folks don't like the ergonomics and it's not as versatile in the shop and it's just a little fragile, something that klutzes like me worry about. +++ #9926 From: Budd Davisson Subject: Re: Re:welding help ( was Progress on #534) I have a henrob too and it's okay on outside welds, but its ergonomics make it awkward on inside clusters and it really doesn't like to weld down into boxes or tight corners because it sneezes a lot quicker than a normal torch does. Still, it comes back to controlling the puddle. Anything that works, works. Weld on, dude! +++ #9928 From: Russ and Penny Erb Subject: RE: O/A WELDING EQUIPMENT > Where can I learn more about the Kent White micro? http://www.tinmantech.com +++ #9930 From: "Corky Scott" charles.k.scott@d... Subject: Re: Digest Number 783 > You are going to say I had too big a torch, or too much heat. What size welding rod are you using? When I've got small things to weld or .o35 thickness tubing that is under 3/4" I often find it's easier to go to a more narrow rod. It flows faster and gives you less of an opportunity to overheat the joint. +++ #9931 From: Budd Davisson Subject: Re: Digest Number 783 You can ask anyone on this list about welding 035. It welds just like anything else. Believe me, if your burning it, you have too much heat. If you didn't, you wouldn't be burning it. On 035, the puddle develops exactly the same as it does on 049. The only caveat is that the smaller the tubing, the more sensitive you have to be to the heat build-up. You say you to resort to "funny things to make the little stuff work: what kind of funny things? +++ #9933 From: "SHARIT,JOE (HP-SanDiego,ex1)" Subject: RE: Re:welding help ( was Progress on #534) I've come to grips with the practice thing. I usually try to spend a half hour a day just practicing welds on 4130 tubing cutoffs that I got from Aircraft Spruce. Right next to my tanks is my copy of "Zen and the Art of the Weld Puddle". I've read it at least six times and keep it handy for reference. I'm thinking that it would be a whole lot easier to learn welding if I had a lesson with an expert. There's so much to learn that trial and error takes a long time: tip size, gas flow, rod type and size. I've enjoyed Kent's 4103 video; that's helped me see what the puddle should look like. It's time for me to check out my local EAA chapter! +++ #9938 From: Budd Davisson Subject: Re: Re:TIG/4130 > You are right on with your welding tips for gas welding. What are > your thoughts on TIG welding 4130 tubing TIG is a great way to weld anything and the skills transfer almost directly from gas to TIG. It has a few drawbacks, one of which is it likes a little tighter tubing fit , or more properly, gas lets you get away with bigger gaps. Also, even if you weld with TIG, you'll still need the gas torch around the shop for heating/bending/distortion control, etc. TIG distorts less because the heat is in the joint for a shorter period of time, which leads to another area of question/controversy. Any welding method causes stresses with in the joint caused by heating and contracting. The faster it is heated and the faster it is cooled, the more stresses (and material change) there are introduced in the joint. Gas heats slowly, heats a big area and can be cooled slowly. TIG can weld instantly (a good welder can creep up on it though) and cools much more quickly. MIG heats and cools in an instant. So TIG can introduce more stresses than gas, although by preheating and post heating/stress relieving those can be cured. Ditto for MIG. All that having been said, Aviat doesn't stress relieve any of their TIG joints and, as of my last contact with them, neither American Champion nor Maule stress relieve their MIG welds. I'm from the old school: I stress relieve any weld done in high carbon steel like 4130. I figure it can't hurt and probably helps. +++ #9942 From: Budd Davisson Subject: Re: Re:TIG/4130 > The reason they can get away with not stress relieving is because the > truss type fuselages are incredibly overbuild for the normal loading > they see in a reasonable lifetime of flying. The cracking that would > take place in the HAZ of a MIG welded fuselage can only happen when > loads cause some flexing. You're probably right and I'm probably wrong, but in various materials labs I was always taught that all trusses flex, even if only microscopically within the confines of the tubes themselves being loaded and unloaded. If we're talking the micro level, then we also have to recognze that welded trusses (not pinned trusses) restrain the members at the intersections causing a slight bending moment right outboard of the weld. The weld actually acts as a mini-gusset. That's why all calculations and tubing strength tables carry a margin of safety in them (15% comes to mind) to take into account both the deterioration of the metal at the weld and the fact that it's restrained and not pinned. In fact, unless I'm mistaken, different tables are used for restrained and pinned trusses because pinned trusses don't have to worry about transferring bending loads right at the joint. The reason this is seldom a problem is because, as you pointed out, tubing structures are usually overdesigned. However, they are only overdesign within the parameters of the design limits originally set. A classic case of what happens at the edge of the design limits is the Pitts Special longeron breaking problem. Flown within the envelop (snaps at 140 mph max), the stresses within the material stayed under the S-N curve that sets the limits where fatigue can begin (45kps comes to mind). If theloads were kept below that level the fatigue life of the structure was infinite. If loads were allowed to go higher, the fatigue life was shortened. The result was classic fatigue failure of the longerons right outboard of the TIG welds, where the material goes from the 30+ Rc hardness of the weld to 2 or 3 Rc right next to it and back up to the natural 18-20 Rc of the tubing within something like 1/4". You won't see embrittled welds break from too much force. You'll see them break from fatigue and usually it won't be the welds that break. It'll be the material next to them because of the abrupt hardness change. Post heating evens out this transition and relaxes the internal stresses that can cause cracks, but it can't do anything about the micro cracks already there that can happen quite quickly with MIG in high-carbon steels, especially in humid conditions where hydrogen is cooked into the weld. We just have to live with them. Like I said, it's a controversial subject that Aviat/Maule/American Champion ignore. Me, I'm just a country boy, but I don't ignore it. Again, like i said, I don't figure pre-heating and stress relieving can hurt anything. Haven't we been through this thread before? Somehow it always seems fresh. +++ #9945 From: "Bruce A. Frank" Subject: Re: Re:TIG/4130 It's always interesting to talk about. You are correct about micro-movement being the culprit. Just the areas that see the loads that work them (gear, engine mounts and wing/strut mounts) are excessively braced. Most of the rest of the fuselage is just along for the ride. The truss construction of a fuselage like the Bearhawk's could support several thousand pounds between the cabin and the tail with minimal deflection. Anyway, I have done a lot of MIG on my fuselage, landing gear and engine mount. I don't pre or post heat the fuselage welds. I do post heat the mount and the gear. What was that plane that had wings that were 4130 welded with stick? +++ #9952 From: "Ron Webb" Subject: Re: Digest Number 783 > You say you to resort to "funny things to make the little stuff work: > what kind of funny things? Well, the biggest problem was the edges burning back. Get the torch anywhere near the edge of a tube I had just spent time fitting tightly, and the edge would burn back, ruining the fit, etc. Anyway, I hit on the notion of laying down a COLD bead with the MIG, then remelting with OA to get penetration. No edges since the bead is already in place, so there was nothing to burn back. And since I was forming the weld puddle in the thicker bead, I got no blow through either. And since the cooling was slow, the stresses should be less. I used mild steel wire and 75/25 gas in the MIG. I've been told this is not good. I admit I don't know why. I'm sure one of you will tell me now though;^} I tested it thoroughly on scrap. No weld done that way ever failed at the weld, or within 1/8" of it, even though I tested many test structures to destruction. The resulting fuselage has been around for several years, and actually used a bit with no cracks that I can see... The wings havent been built yet, but it makes a truly memorable go-kart - and I WILL finish it as soon as... The end of the story is that only a few joints were done that way, because in the process, I got good enough with the MIG to rely on that alone for most of the structure. I got a close look at a Maule the other day, and my welds are better'n that! +++ #9954 From: "Corky Scott" charles.k.scott@d... Subject: Re: Digest Number 784 > Well, the biggest problem was the edges burning back. It sure sounds like you have too much heat with the tip you are using. When I'm welding something like 1/2" .035, if I've modified the flow properly, I don't instantly melt back edges. It takes some care to get things set properly, and once they are you still need to be careful and keep the filler rod inserted constantly to modulate the puddle and control the heat. This with constantly moving the flame around so it doesn't concentrate too much in one spot. I've seen a guy weld tin cans. Metal doesn't get much thinner than that. +++ #9968 From: "Bruce A. Frank" Subject: Welding Corky has a point that we have sort of left out of this discussion, manipulation of the filler rod. When material seems too thin to allow establishment and control of the molten puddle the fill rod can help. Lay the tip of the filler rod in the joint and concentrate the heat on the rod rather than the edges of the joint. As soon as the first bit of filler starts to melt continue to feed filler to create the puddle. This gives you a thicker area that can handle the heat. You then use the torch and filler to build on the puddle and lead it along the seam. Don't think that the weld has to be maintained as a continuously molten and moving puddle. Once you create that first buildup of filler rod, move the torch away....let things solidify and cool slightly. Then come back into the weld area and again concentrate the heat on the filler. As the puddle establishes again add some filler. The filler rod in your hand can be used to cool and solidify the puddle in the joint. Two ways to control the heat and prevent melt through is by moving the torch out of the joint and moving the rod into the joint. Dipping the tip of the rod in the molten puddle chills it. DO NOT try to maintain a small bead. Add filler to establish a large enough bead of filler so that you can work the flame backwards and side to side as necessary to prevent overheating and melt through. If you feel you just can't control that moving puddle then don't do it that way...establish the puddle, add filler concentrating the heat on the rod to enlarge the puddle then pull the flame away far enough to allow the puddle to freeze. A little point here, usually it is best to move the torch away to reduce heat in the puddle but keep the tip of the flame playing on the fillet ...just pull back enough allow the molten puddle to freeze. Once the molten puddle has solidified you can pull the torch away. The play of the flame over the molten puddle keeps atmospheric oxygen away from the melted steel. If you keep having problems with bubbles and holes forming in the bead as you pull the flame away you are moving too quickly allowing oxygen to react with that molten steel. Once the puddle freezes and reduces the chance of melt through, move back into it with the torch and start the melt and adding filler process again. As long as the molten puddle is re-established each time you are fusing each addition to the last. Use that filler rod to control the heat. The rule of thumb in general welding that the diameter of the filler rod should equal the thickness of the base material. That isn't practical or desirable when welding thin material with a torch, or even with TIG for that matter. Regardless of the thinness of the 4130 tube I rarely drop below 1/16" (.063-.065) diameter filler rod because it is so useful, and actually necessary, in controlling the puddle. Hope this helps. +++ #10499 From: rick smith Subject: TIG welding w/ stainless filler On the Lincoln Electric website they indicate that many race car builders use 410 or 412 stainless filler rod when TIG welding 4130. I welded up a couple sample clusters to try it out and the puddle is exceptionaly easy to control and the finished welds have a beautiful sheen and flow well into the base metal. Any downside to using stainless filler rods for aircraft? The joints certainly seem tough enough. I pounded one flat with a sledge and there didnt seem to be any cracking. +++ #10502 From: "kgward2000" Subject: Re: TIG welding w/ stainless filler We used 309 ss rod on #357. It's traditionally used to weld stainless to mild steel. +++ #10503 From: "Kent White" Subject: RE: Re: TIG welding w/ stainless filler I cannot find good reason to recommend stlss on 4130, but 309 has been a tradition for many racecar fab guys since 1970's. Well-tested, I hear. I do not know about the potential of carbide precip. with any of the stlss fillers. +++ #10504 From: "Bruce A. Frank" Subject: Re: TIG welding w/ stainless filler 410 and 412 work very well for 4130 with the advantage with TIG that there are virtually no sparks are popping. These 400 series stainless allows wet out and flow to make very nice beads. I find that the 300 series stainless whether 304 through 316L have a tendency to stand up and look a little ropey. As I have said here several time I find the ER70s-6 to be superior in flow and bead formation with a very quiet puddle. Stainless filler always acts a little funny TIG welded on steel because stainless and carbon steel conduct heat at significantly different levels. Nothing that really presents a problem but in general 410 and 412 will give a higher level of finished quality with virtually no pin holes or bubbles and er70s-6 will run a very close second . +++ #10507 From: "Bruce A. Frank" Subject: RE: Re: TIG welding w/ stainless filler From the first start of recommendation that that stainless be used for 4130 welding I have wondered what happened since those classes I took on the Metallurgy of the Weld bead teaching that carbide precipitation was a problem. Once AWS put out a paper saying that it was OK I began to experiment. 316L gave me the best results but did not weld smoothly on 4130, always wanted to leave a bit of a raised toe and the stack of dimes picture was more difficult to obtain...But the welds were stronger and the elasticity of the stainless seemed to reduce the distortion of the welded structure. I continue to find that TIG welding using the ER70s-6 filler rod, originally formulated for MIG work, to give me the best of all worlds. +++ #10513 From: Ken Beanlands Subject: Re: TIG welding w/ stainless filler I gotta tell ya, after last night, I'm buying a TIG welder. I ended up with a pair of Piper Tomahawk seats for the Christavia. These are reat seats, lightweight with track rollers and no structure below the seat pan for easy adaptation to any fuselage. The original rear seat was going to be a bench seat and there were some tube frames welded into the fuselage to support the seat. However, the sear angle was not very comfortable. So, after removing the offending tubes, I had to weld in two fittings at the rear of teh cabin to support the rear of the seat. Of course, the fabric is already completed in the fuselage so I had to protect the area wth lots of fire brick and plate steel to prevent melting the fabric. I was working in a 30" x 30" space with a 10" flame coming out of the torch. Needless to say, it was a hot, uncomfortable way to spend an evening. Fortunately, there was nothing burned that shouldn't have been (except my arm) and the only damage was a tiny rip (1/4" diameter) to the interior fabric where the corner of one of the plates dug in. I think this could have been done a lot easier with a TIG welder. +++ #10531 From: Russ and Penny Erb Subject: RE: This Weeks' Builder Tip 'Filtered Box Fan' > http://www.woodworkingtips.com/etips/etip020705ws.html Anyone painting > their Bearhawk, a nice addition to your' face mask ;-) Actually, I've thought of doing a similar thing to use while welding. The oxy-acetylene torch seems to produce a lot of soot that seems to travel to all corners of the workshop and settle. Maybe this would collect some of it. +++ #10611 From: "Donald Schlaud" Subject: Re: (OT) Welding cast aluminum I have a question that is not quite related to bearhawks, but I know there is a lot of expertise in this forum. Besides, I need to make room to build my bearhawk by getting these projects finished :-). I need to weld up a cracked bellhousing on a GM transmission. It is aluminum and I was wondering what type of rod and technique I should use in repairing it. +++ #10615 From: "HAL" petz187@... Subject: Re: (OT) Welding cast aluminum I would use 4043 rod, it's a good all purpose rod, and I'd Tig weld it together. +++ #10617 From: "Bruce A. Frank" Subject: Re: (OT) Welding cast aluminum No! Do not use 4043 on automotive cast aluminum. The correct TIG filler for cast aluminum intakes, heads, trans and bell housings is 5356. 4043 *IS* a good all 'round filler rod for sheet and machinings, but, though there is a chance you can get it to work on a bell housing, you'll likely be chasing cracks half way around the block. Also 4043 doesn't want to mix into the puddle on the casting very easily. Get some 5356 and degrease the bell housing as much as possible and mechanically clean vigorously with a new clean stainless steel wire brush and you should get beautiful job. +++ #10620 From: "Kent White" Subject: RE: (OT) Welding cast aluminum I think I can give you a workable solution. Clean the area with rubbing alcohol and ss brush both sides, and vee the crack 60%deep 45deg and on outside. Stop drill the end with 3/16 twist drill. Wash again. Tack weld firmly at the open end, and at 3" spaces down the crack with 5356 filler. Preheat to 300 or so with torch and weld in skips 2" long with 2" gaps, from open end. Lightly peen welded segments (weldscale hammer) until cooled down, to relieve stresses. ping ping ping, not bam bam bam. 4043 will break at this point. Weld remaining gaps. Peen them and then whole length to when cooled to where wet fingers can touch firmly. This is the fail-safe method for cast. Although there are variations. +++ #10632 From: "Bruce A. Frank" Subject: Re: (OT) Welding cast aluminum TIG weld a cast iron block....wellllll......yes....sorta'. If I had a crack in a cast iron block or head or intake (not exhaust manifold) With proper preheat I would go after it with TIG and SILICON-BRONZE or certain alloys of NICKEL SILVER. It may be possible to repair that structural part that holds the starter with either of these fillers and TIG, but it is very difficult to create a puddle with filler and cast iron because the activity, sputtering and popping of the "dirty" cast iron almost instantly contaminated the tungsten. And your object with these types of fillers is more of a brazing repair in which case you really don't want the base metal to melt and get involved in the "puddle". TIG welding over a crack to prevent water or oil leaking if different than making a structural repair in cast iron. A better way would be with the oxy/acet torch using a good quality brazing flux, the silicon bronze or the nickel silver fillers. The torch heats a larger area reducing the chance of cracks and also the torch handles the impurities that boil to the surface as you make the repair. There are also high nickel cast iron filler rods intended for oxy/acet repair of cast iron. Now, my personal choice to make a structural repair to cast iron is stick electrode. There are specialty rods that allow almost fool proof repair of cast iron. Most welding shops will carry or can get "repair" rod that is usually a very ductile high nickel rod that with proper preheat will make the repair with virtually no chance of cracking. The flux on these rods contains all that is necessary to suppress porosity and provide the alloying ingredients to provide the strength needed. But, most all of these processes require peening which can be an art in itself. If I were you and really needed to save this block I'd call a welding shop that has the cast iron experience or specializes in cast iron block repair. If you haven't done it before, I would not learn the process on something you really want to save. Maybe Kent can provide another approach since he has developed some phenomenal procedures with many metals. +++ #10647 From: "Kent White" Subject: RE: (OT) Welding cast aluminum ....Welding and brazing of all kinds are used to repair cast iron parts. ...even GM. If you know how to weld with a stick then you can do the repair, if you watch the video first. I welded a broken block...in the truck... cross the pan rail, up by the mains, and out past the starter, and back...Big Chunk. Without preheat, or postheat, and no peening...saved hours. It is a 4WD plumber's truck, still going. No leaks. http://tinmantech.com/html/cast_iron_welding_with_torch_a.html It also covers Torch and NiRod stickweld-and-peen methods. +++ #10823 From: Russ and Penny Erb Subject: Changing Welding Paradigms WELL KRAP!!! Now I have to make another change in my approach to Bearhawk building, and I blame it all on you guys, especially Kent White! 8^) You would think that changing paradigms would be as easy as trading them for 4 nickels. What the heck is Erbman talking about? Welding torches, of course! Back in 1996 I learned to weld through the local community college with a huge torch suitable for welding up the set of Waterworld. (In fact, that's what we did--our steel coupons were cut up from the leftovers from the set of Waterworld.) Then in 1999, I was intrigued with the Henrob 2000. It had a lot of features that were better than the torch I learned on, including a better focused flame, a softer flame (lower velocity), and it operated at lower gas pressure. It also has a really good cutting attachment (that even budd likes), but that hasn't been real useful for airplane building. I had good reviews of the torch from a friend, so I bought one at Sun N' Fun. I'm happy to say it lived up to all of its advertising. The one drawback was its weight. Kent has referred to it as the "Arnold Schwartzenegger" torch, and after holding it for an hour welding up a cluster, you'll believe it. Sometime after that, budd and Kent joined the Bearhawk list. budd was singing the praises of the Smith torch, while Kent told us of the Meco Midget torch, which he happened to sell. In an outstanding demonstration of the soft sell, Kent merely told us the torch existed, and left it to the rest of us to sing its praises. Kent harassed me about having Schwartzenegger arms, while pointing out the incredibly light weight of the Meco Midget. I was intrigued by this, and figured that I had a good 3 years of service out of my Henrob torch. Thus, at Oshkosh I picked up a Meco Midget at Kent's demo booth and found all that he said was true. Later I went by the TM Technologies booth and purchased one, complete with the ultra-lightweight hoses. I tried it out tonight, and it was so light by comparison that I couldn't tell I was holding up the torch. In fact, I considered adding some ballast weights so it would "feel better". The flame quality and pressures were just as good as my Henrob. BUT.... I think Kent is missing another major point in his marketing strategy (or I just missed it). On the Meco Midget, the control knobs are positioned where you can adjust them with the hand that is holding the torch (one handed operation). Other torches, like the Henrob, required two hands to adjust. One handed operation is INCREDIBLY USEFUL as you can adjust the flame for regulator fluctuations or turn the heat up or down without abandoning the current weld. That is, you don't have to pull the rod away from the puddle to adjust the flame. Well, I know which torch I'll be recommending to everyone who asks now--the Meco Midget. The bad news is I'll have to find something else to exercise my forearms. The good news is that Kent already sells this torch, so I won't have to set up my own company to make this torch available to you. There are many torches out there that will do a fine job, but the Meco Midget does it with the least effort and workload on the part of the welder. If you haven't bought a torch yet, this is the way to go. Even if you have another torch, you owe it to yourself to try this one--I betcha you'll like it better! But, PLEASE, DO NOT buy a Meco Midget for budd davisson, especially if you really like his novels or articles. If you do, he'll like it so much Marlene will never be able to get him out of the shop! Sure, he'll be having a blast fixing up his roadster, but he'll forget to write articles for you to read! +++ #10824 From: Dennis Mingear Subject: Re: Changing Welding Paradigms I don't like "me too" e-mails much, but I also bought the Meco Midget from Kent and it simply puts the Smith Airline to shame. My hands just don't bend and move like anyone else's. Compared to most folks I would be catorigized as a physically challenged individual. Even with my handicap the Meco is simply a joy to use. Keep in mind that I'm a total novice who is still working on his rib form block while learning to fuse steel scraps together in his garage, but now that I've used a Meco I wouldn't recomend anything else for the kind of gas welding done on these kinds of aircraft. I'll keep my Smith, but I'll only use it to cut and weld rebar for my lawn art projects. The Meco Midget torch is simply "THE BEST". +++ #10831 From: Dennis Mingear Subject: Re: Changing Welding Paradigms > Ok you sold me web site please. looks like the one for me. http://www.tinmantech.com/ +++ #11205 From: Russ and Penny Erb Subject: RE: Gas welding outfit > Can anyone suggest what I will need for the gas welding. I know about > the Mico Midgit torch, but what should I do for the rest? Since no one else has picked this up... With the Meco Midget, get the ultra-lightweight hoses or you miss the whole point of having a lightweight torch. With those hoses will come adapters to connect them to standard regulators and hoses. You don't need any special type of regulators. The "standard" ones you can get at the hardware store or welding supply store will do. I started out with a "B" acetylene cylinder (40 scf, requires a special adapter to fit the regulator) and 55-58 scf oxygen. That worked fine until I started finish welding the fuselage. Then I "upgraded" to a 65 scf acetylene and 83 scf oxygen cylinder so that I wouldn't have to exchange them so often. As for rent or buy, you'll need to talk to your gas distributor. What you want is to be able to walk in with empty cylinders and a few bucks and walk out with different full cylinders (i.e. exchange cylinders). With my distributor, I "bought" my cylinders, but what I really bought was rights to a pair of cylinders. The actual cylinders I have changes each time I exchange them for full ones. If you get locked into one pair of cylinders, you'll have to wait days while they go off to be filled and come back. Also, you, instead of the company, will be responsible for the hydrostatic tests. If you constantly exchange cylinders, the gas company takes care of that for you. +++ #11206 From: "Kent White" Subject: RE: Gas welding outfit Russ knows.... Get the rental/lease tanks. B acet and 60 OX are good for starts. Use any regs. The MECO is light and handy and the black hose is great. +++ #11213 From: "Kent White" Subject: RE: Re: Gas welding outfit > One more question though. What tips should I get? Tips #2,3,4 will do fine. The #1 is with the torch. Using wire drills, the tips may be resized to specific tasks. Victor offered half sizes during WW2 for the airframe welders. +++ #11218 From: Jimmy Mathis Subject: RE: Gas welding outfit I lease two "industrial" size cylinders for a yearly fee of $52.00 apiece. This is tax deductable since I have a small business on the side. >>> 20may03 #11298-18250 +++ #12360 From: shanspur@w... Subject: Re: Re: We make the mistakes so you don't have to... Rod's technique reminded me that in jig shop when we need to weld 2 or more bushings in alignment, many times we can slip a piece of drill rod of the proper diameter through the bushings. Then after the welding process has pulled them crooked enough to bind up the drill rod, drive it out with a hammer and punch, lap it out to free fit and you're done. It ain't perfect, but it does the job. Of course, I'm talking about hardened steel bushings. The drill rod comes in three foot lengths standard - longer by special order. Our crib only stocks up to 1 inch dia. If you have an extra piece of the tubing that will go in your bushings, use that for alignment. Judicious tapping with a hammer should correct most weld induced misalignment. Keep on keeping on Shannon +++ #12364 From: "TheStones" Subject: Re: Re: We make the mistakes so you don't have to... Another trick I've seen is to leave the bushing tubing full length across, then after welding cut out the excess and trim for your bushing length. TimS. +++ #12365 From: Russ and Penny Erb Subject: RE: Re: We make the mistakes so you don't have to... If you do weld a tube in place with another tube inside it (a "mandrel"), I've found a way that helps get the mandrel tube out. First let it cool so that we don't shock the 4130. Then spray some penetrating oil between the tubes. Then tap it out with the hammer. The oil makes a huge difference--what wouldn't move at all now moves "easily". Russ Erb +++ #12414 From: "Kevin Griffith" Subject: Welding Rod What type of welding rod should be used to gas weld 4130 tubing. The book I have suggests either mild steel or 4130 rod. Aircraft Spruce has 4130 rod at $62/lb and mild steel at $4/lb for 1/16 inch. Is the 4130 rod worth the added expense? Thanks for all the info distributed on this site! Kevin (#517) +++ #12415 From: Budd Davisson Subject: Re: Welding Rod DO NOT WELD WITH 4130 ROD! It's a class one pain in the butt and totally unnecessary unless you're going to heat treat your entire fuselage. You don't need anything exotic, just old fashioned copper coated mild steel. This is going to kick off another blonde's versus redheads versus brunettes debate, but none of the more expensive rods offer enough advantages to make them worth while. A few flow "a little" better but again, the difference isn't worth the effort. Don't complicate your life. bd +++ #12417 From: "Bruce A. Frank" Subject: Re: Welding Rod As Budd said, do not use anything other than mild steel filler rod. I prefer ER70S-6 because it makes a very quiet molten puddle due to the deoxidizers and scavengers contained in the rod, but ER70S-2 or -3 will do. There are super rods sometimes called "vacuum melt" or "triple deoxidized" for premium prices, but they offer little or no advantage over ER70S-6 (which locally here in San Jose, CA sells for $3.00 to $6.00 a pound bought 1 pound at a time...10 lbs runs about $23). I have used them all and none offer advantage enough to make any of them worth the higher prices. 4130 filler will actually cause most welders problems (cracks and pin holes) unless used correctly. And do not fall for the claim that since you are only using a few pounds just buy the best. The FAA repair and maintenance manual says use "mild steel rod." Mild steel filler rod is not just "adequate" it is superior for welding truss frame airplane fuselages constructed with 4130 alloy steel tube. +++ #12418 From: "Kent White" Subject: RE: Welding Rod Is "this book" written by RF? If so, use salt, and a lot of it. er70s3 is recommended by some welders, and the S6, too, I think. Many use the copper coat, RG45, and the copper may be steelwooled off. Or the RG60, bare rod, but does not flow or penetrate as nicely as the copper-coat does. No, do Not Use 4130 rod, unless you wish to heat treat (harden) the unit completely, which excludes nearly all tubing construction. Kent +++ #13010 From: Russ and Penny Erb Subject: Why you should wear 100% cotton... Note: If your name is "Lee Erb" close this message immediately and delete it. (You didn't do it, did you? You've been warned--no whining!) Alternate subject lines: 1. Less than successful welding techniques 2. Bearhawker on fire! 3. Don't Panic! 4. Years of Emergency Procedure Training Pays Off 5. Uh...I need a new sweatshirt... 6. Things Your Spousal Unit Would Rather Not Hear About But Will Anyway 7. Bearhawk Safety Meeting 8. Public Humiliation Shall Be Your Punishment (Explanation of #7 and #8: In my experience in the Air Force, when you do something really stupid, especially when no one is injured and no aircraft are lost, your punishment is to stand up in front of your squadron at the next safety meeting and tell them what you did, in hopes that others will learn from your stupidity) Well, the Erbman has done it again--created some excitement in the shop... I've been welding on the rear cargo door, and everything was progressing nominally. I was working on a section that was along the edge of the table closest to me. I was standing close to the work to see the other side where the puddle was. Since the shop is around 50 to 60 degrees F, I was wearing a T-shirt covered by a sweatshirt. Unbeknownst (a lovely word) to me, the welding flame was being deflected by the tube right toward my navel region (which has nothing to do with my friends on boats). I started to notice a warming in the navel region, and assumed it was due to the radiation of the hot metal, as has happened many times before. I responded by backing away from the hot metal a few inches while continuing the weld. This has always solved the problem before. A few seconds later, I noticed the same warming again. Being somewhat perplexed by this, I glanced down to my gut to see flames emerging therefrom. Of course, this is when things started to get exciting.... It's amazing how fast your brain processes in situations like this. The following took less time than it did to read this sentence. Now flames have figuratively come out of other orifices in the past, but those orifices were generally connected to digestion. By this time, the burning hole in the sweatshirt was about 3 inches in diameter and the flame was about 3 inches long. Sensing this was bad, my first reaction was to swat at the flames. After a couple of swats with one hand and no success at extinguishing the flame, I figured that wasn't going to work. My next idea was to strip the sweatshirt off. For that I was going to need both hands, and one hand was currently occupied by a welding rod and the other was occupied by a lit welding torch. I went to put down the torch and looked toward it to see where I was putting it. At this point I noticed that I was about to put a lit torch down on the table, and envisioned the problem rapidly getting worse. At this point, my training kicked in. Granted, I haven't been to a class that specifically discussed what to do with a lit welding torch while your belly button is on fire, but I have been to plenty that talk about how very few things will get significantly worse if you take a couple extra seconds to respond in a logical manner than if you rush and panic (which tends to make things worse). I told myself "Don't Panic" (an actual mental quote) and realized that since my navel didn't feel incredibly hot, the skin probably wasn't burning yet. Therefore, the first priority was to get the welding torch shut off. I turned the fuel valve to off, killing the flame, and probably shut off the oxygen too just out of habit. Dropping the torch and rod, I now looked again toward my gut where the next priority was. Still looking through my welding goggles, I grabbed for my sweatshirt with both gloved hands. Flashing through my brain goes "Stop, Drop, and Roll" which has been on one of those goofy Fed Ex commercials lately. Realizing that falling to the floor amongst the various tubes and stuff was probably not real practical, it occurred to me that a better option to pulling a flaming sweatshirt over my head, hair, and welding goggles would be to go at the flames with both hands (still in leather gloves). A couple of swats and the flames were out. Crisis contained. Of course, my brain is now screaming along supersonically trying to catch up to figure out what just happened. Assessing the damage, the sweatshirt was a mort, having a rather large charred hole in it. BTW, it was 50% cotton, 50% acrylic. Feeling the way it had burned, I'm now looking for 100% cotton, which is generally considered safer (cotton burns to an ash, unlike nylon which melts into your skin (very bad!)) for fire. The underlying T-shirt was slightly darkened, but otherwise intact. The skin in the navel region was undamaged (other than the excess fat underneath...). Therefore, I'm uninjured other than just feeling a little more stupid...even though this experience all seems quite humorous, which is why I had to share it with all y'all... MORAL: Don't stand too close to where you're welding! (Like I should really need to tell anyone that...) Feel free to respond with any "There I was...on fire..." stories (or other stories) that this may have reminded you of... Russ "I'm On Fire" Erb +++ #13022 From: Russell Bell Subject: Re: Wearing Cotton doesn't help This is all pretty darn funny. The ones I hate are the pieces of slag that drop in a boot. Anyhow, one other way to partly fireproof your cotton coveralls is to starch them heavily. Doesn't actually fireproof, but it makes the sparks bounce off pretty well. Good old Faultless starch is getting hard to find, though. Russ Bell +++ #13025 From: "ken wardstrom" Subject: fire resistant coveralls We used to use standard coveralls soaked in a solution of borax and water and let them hang dry. ( poor mans driving suit ) No idea if it works on beards.-ken +++ #13047 From: "rodsmith52 Subject: Re: New thread: nomex flight gear I cant agree about nomex losing its fire protection quality after being washed. I think there is a misperception about nomex. It is not designed to offer fire protection from heat or direct flame. Its sole purpose is to not catch fire itself and add to your problems. A thin nomex garment offers next to no thermal protection. If it is oil soaked it will burn also. Last week we had a flash fire at the plant. One of our instrument techs was in the center of the fire ball wearing a well used pair of nomex coveralls. The only damage he sustained was singed eyebrows and mustache. Some cotton rags next to him caught on fire and he had to put them out. He said the little lint balls on his coveralls burned off. You are not supposed to wash nomex with other fabrics for that very reason. Rod Smith #246 +++ #13059 From: "csdurham81503" Subject: Re: New thread: nomex flight gear I've made my living for ten years in a blue nomex suit (well, more than one, OK). I worked in a refinery and now in a bulk products terminal. The folks we buy our suits from do make pants and shirts, some that look for all the world like denim. One big plus is, after it's been washed a few times, nomex is cooler than cotton. So, down there in the Arizona summer you could look like you're normally dressed and be cooler to boot (pointy-toed ones). As an aside, nomex is for flash fire protection. Prolong the exposure and you will burn.... Try these folks: www.workrite.com; www.bulwark.com P.S.: Make sure you're sitting down when you get to the prices.... +++ #13110 From: "nauman_alan" Subject: O/A tanks I just called a local place about leasing the tanks and they told me that it would be cheaper to buy them. I was told that if I buy them, then I would just exchange them each time I needed them filled. If I leased them, then there is a the same yearly fee($75) for all tank sizes. He said I should just buy the tanks wherever I can get them the cheapest and then exchange them wherever it is most convenient. $100-200 once sure would beat $150/year all other things being equal. Is there more to it? Am I missing something? Thanks Alan +++ #13011 From: Budd Davisson Subject: Re: O/A tanks No, you're not missing anything. The reason the discussion of leasing versus buying is held is that some states won't allow you to own the tanks and it gets confusing when folks from different states start comparing notes. Incidentally, get the medium sized or large tanks, not the small ones. They run out too often. I've forgotten the proper designations of the tank sizes, but someone will chime in with them. bd +++ #13118 From: Russ and Penny Erb Subject: RE: O/A tanks I use the 55 SCF Acetylene and 84-92 SCF Oxygen tanks. These are about twice the size of the "B" acetylene tank and corresponding oxygen tank that I started out with. They last longer, and are about the largest size I feel comfortable moving around myself and lifting onto the vehicle for transporting. Russ Erb +++ #13125 From: "Kent White" Subject: RE: O/A tanks Well, Budd is right, as all things be equal in your local area, and not elsewhere. Go ahead and buy the B acet and 60 Oxy, as these will be the minimum reasonable size. Our local welding outfit (No. Cal) works it a different way, where leasing is cheap, and you don't have to wait for your bottles to be refilled, and no periodic inspections to pay for. I started with the B and 60 combo years ago, doing lots of torch work aside from my day job (doing metal work at Harrah's.) After I opened my shop we got another set of tanks, twice the size, but I still use the medium set. Kent +++ #13132 From: John Thompson Subject: O/A tanks Alan, if you buy the tanks, then trade them in for full ones when needed, you are effectively buying a new set of tanks for the dealers stock. Around here, a 5yr lease on a set of tanks (forget the size, but about 4'-5' tall each), is $275 or so. Purchase is a bit more, but you'd have to wait to have the tanks filled. Tanks the size being recommended here >should< last you through building a bearhawk (you guys working on the fuse can correct me if I'm wrong) if you do nothing else except for practice. Just so you know, I've got my welding outfit, but no tanks yet. I've only looked into the prices so far. I'm afraid if I get the tanks, I'll find excuses to find something to weld (non-aircraft welding, that is). This subject seems to come up frequently on science.engineering.joining.welding. John +++ #13133 From: Budd Davisson Subject: Re: O/A tanks I don't know of but a few places around here who even have the capability to fill your tanks while you wait. Traditionally, even thought you buy the tanks, you don't ever see them again because you're continually trading them in for a full set. bd +++ #13135 From: "John" Subject: Re: O/A tanks Something to watch out for if you buy your own tanks. You buy your nice new tanks and the first time you take them in, they swap them for some old tanks that are just about to run out on their certification. Next time you take them in, you find out that they will not accept them as they need to be re-tested. Gotcha! They have new tanks and you have junk! I've seen it happen and there were some VERY upset people involved.... Leasing is more expensive, but the gas company is responsible for the tank testing as they own them. Lots of places just exchange tanks. They send the empties out to be refilled, and if you want YOUR tanks returned, you may have to wait quite sometime to get them back. That sucks if you run out of gas in the middle of a project. Read the fine print on your contract with your gas supplier. John Kozak +++ #13136 From: Alan Nauman Subject: Re: O/A tanks I talked to another place about buying the tanks and they told me the purchase price was $285 including tax for the tanks. That's a 4' tall O2 tank and the smaller acetylene tank. The lease price I was told was $75 per tank per year. Basically, it you are going to have them for 2 years or more, then it is cheaper to buy. If you do end up with an expired tank, then there is a $13 inspection fee when you trade it in. Thanks to everyone for the recommendations. Alan +++ #13157 From: "Tim Anderson" Subject: Re: O/A tanks I bought my tanks in San Antone, there is a couple of welding places around the old colisuim, had no trouble trading at any gas supply place, even in Sequin. I bought the taller O2 and waste high Acet. tanks. The larger O2 seems to needed if you do a lot of torch cutting, which is why the salesmen recommened that size. For the type of welding I have done do far, the larger O2 tank is probably not needed, I think i usually ran out of Acet. more frequently, but cost wise you get a bigger bang for the buck with larger tanks. Tim Anderson +++ #13641 From: Tony Dean Subject: Welding equipment I noticed that Harbor Freight has an OxyAcceteline welding kit of their house brand. I was planning to wait until I needed it and buy a name brand which would more likely be a Harris or Victor. I asked someone about the Harbor freight outfit as I am aware that brand name producers often sell all sort of tools under generic brands. Someone told me they thought that was what Harbor Fright had there. Has anyone used this kit? Is it a variant of a name brand? Do parts interchange with any of the name brand products? The $99 price tag sounds great, but not if its junk or if it is impossible to get replacement parts for. Regards Tony Dean +++ #13645 From: "Kent White" Subject: RE: Welding equipment The Chinese are always trying to sell me their brands, which look just like Harris, Airco, Purox, Victor. Cheap, looks like... but ... you may end up "buying it twice" and so why not get the nomex 2.1 OS right now? Kent +++ #13647 From: "Bruce A. Frank" Subject: Re: Welding equipment The Smith Airweight or Aircrafter or something like that used to be and may still be the standard, but it is not cheap. It has forward controls and holds the settings. Smith and Harris gauges/regulators used to be some of the best in the industry. Now I cannot tell much difference in any of them. Not disregarding what Kent says about his recommendation of the Nomex system (with which I have no experience), but if you are not going to do much more than build your Bearhawk, even the cheapest NAME BRANDS will probably be sufficient. A full selection of welding tips and a good set of tip cleaners is necessary. Don't neglect the smallest tips. Everyone uses different designations but the Victor "0" and "00" or other brand equivalent are necessary. When using oxy/acet I use a very old, bought as a trade in from a welding supplier, Smith. I also have a Victor, or I should say three slightly different Victors and except for the fact that they are a little larger and heavier than the Smith, they all work well. Small diameter light weight hoses for the last 8 to 10 feet connected to the torch helps a lot. All of the known brands; Smith, Harris, and Victor have worked well for me. Even their inexpensive promotional outfits do a reasonable job. I have not had any experience with the Henrob type pistol grip outfits but many people swear by them. Bruce A. Frank +++ #13651 From: Russ and Penny Erb Subject: RE: Welding equipment I've given up my Henrob 2000. It still works as good as the day I got it, and I did weld the wing parts, tail feathers, and fuselage with it. But since I bought the Meco Midget from Kent at Oshkosh this year, I haven't looked back. It's a wonderful torch for what we're doing and I'll stand up and recommend it to anyone who'll listen! (Okay there was one time after getting the Meco that I used the Henrob because I needed a larger tip than the Meco would handle--for some reason the Henrob just didn't seem as nice anymore after using the Meco--sort of a "How Ya Gonna Keep 'em Down On The Farm After They've Seen Paris?") I've never seen or used a Smith torch, and they must be good because budd likes them, but I'm so happy now with the Meco I'm not even interested in trying any other torches. Russ "One of these days Kent will finally quote me on his web site" Erb #164, Rosamond CA +++ #13652 From: Del Rawlins Subject: Re: Welding equipment Another point not mentioned is that the major US brands like Victor and Smith can be sent to their respective manufacturers for rebuilding if need be. Try that with your harbor freight special. -- Del Rawlins +++ #13666 From: Sam Butler Subject: RE: Welding equipment Buy a good quality torch, you won't be disappointed, i've used the harbor freight one, and from my experience you'll pay for it several different ways, one being cheap seals that start to break up, and leak quite soon. I bought a torch setup from airproducts, which is a welding supply all accross the country which carries their name torch which is made by victor, and has worked out well for me. Sam +++ #13668 From: "t18cox" Subject: Re: Welding equipment I agree with Russ about the Meco Midget. It is very light and with the lightweight hose Kent recomends handles beautifully. One thing that has not really been emphasized is torch size. Most of the deals you will find on torch outfits have a torch that is to large for the 100's of hours you will spend welding on this project. The small Smith is a nice size in a conventional shape torch, but I don't think the new ones are as nice as those built 30 years ago. The valves just don't seem to adjust as well. Another point about the Smith is tip prices. About $30 each. Bill Cox #303 +++ #13673 From: Ken Beanlands Subject: RE: Welding equipment I also bought the Meco Midget and absolutely love it. I only wish I had it back when I was welding the Christavia parts. Of course, if you're going to buy the Meco Midget, make sure you have them include the lightweight hoses. I cn't believe how easy it is to maneuver around the work pieces with this torch and hose combination. The only very minor complaint I have on teh setup is that the hoses could be longer in their stock form. However, you can always add another hose or do as I did and attach the light hoses o the end of the original thick hoses. Ken Beanlands B.Eng (Aerospace) +++ #13675 From: Shawn Harrison Subject: RE: Welding equipment I've been thinking that I would get the Meco Midget, but now this raises a question. What is the largest tip that the Meco will handle, and what is the largest tip that is needed to build the Bearhawk? Being an economy-minded guy, I only want to buy one welding rig. (Buying two and three of every tool would begin to make a quick-build kit look economical to me.) So, if I buy a Meco, can it do everything I need to do building the Bearhawk? Or is there another rig that's high quality and can handle every situation? Thanks, Shawn Harrison #569 +++ #13691 From: "Kent White" Subject: RE: Welding equipment After using many torches for a while, and making parts for a lot of stuff over the years, I have come up with a #7 tip for the Meco N that I use for heating large steel sections for hot work. I made a long neck to get the volcano's heat onto the part and off of my hand, as the standard dainty neck at 4" is not quite long enough for the blast the #7 produces. I have welded 3/16" 1018 steel plate in a butt weld and 1/8" aluminum in a butt weld also, using a #5 tip on the Meco N. Kent +++ #13728 From: "Kent White" Subject: RE: Welding equipment We make the ULW black hose now in 10 ft. lengths instead of the previous 9ft., but I feel for gas flow and safety reasons (personal experience in my shop) not to make it any longer. Not all welders are careful folks, and those long thin black leads can be punctured, melted, stomped, nicked, gouged, or tangled quite easily. Using a stout "leader" hose will enable torch and gas flow to safely reach the project. Kent +++ #13741 #13728 From: "Kent White" Subject: RE: Welding equipment We make the ULW black hose now in 10 ft. lengths instead of the previous 9ft., but I feel for gas flow and safety reasons (personal experience in my shop) not to make it any longer. Not all welders are careful folks, and those long thin black leads can be punctured, melted, stomped, nicked, gouged, or tangled quite easily. Using a stout "leader" hose will enable torch and gas flow to safely reach the project. Kent +++ #13752 From: Russ and Penny Erb Subject: RE: Welding equipment Shawn--I can't answer directly from experience, but I can tell you this: The condition that required the largest tip in my experience was welding the clusters on the fuselage. I did these with the #2 tip on my Henrob 2000 (didn't have the Meco Midget yet). I just went out to check, and the #4 tip (the largest available) for the Meco Midget is slightly larger than the #2 tip for the Henrob. Therefore, I would say that you would be able to weld those clusters with the Meco Midget. As I type this, I'm reminded that I did weld the landing gear/wing strut fittings using my Meco Midget. Those had as much metal around them as any of the other clusters. Shawn--send your money to Kent for the Meco Midget. Get the lightweight hoses too or you'll miss most of the benefits that make the Midget my favorite. Order the #0, #1, #2, #3, and #4 tips, and don't forget the "fish" (tool for holding and removing/installing the tips). Russ "No, I don't get a commission from this" Erb #164, Rosamond CA +++ #13753 From: Tony Dean Subject: Re: Welding equipment Sams does not seem to carry the Victor unit these days out in the Denver area. The Harbor Freight unit is $99.00 but I have not seen a name brand unit out here for less than $200 in a while. Even saw a store brand earlier this evening for $199. td +++ #13763 From: Budd Davisson Subject: Re: Welding equipment Folks there are only two torches worth buying, the Meco and the Smith AW-1 Airline series. Both have front valves and use the light hoses, both critical to aircraft welding. Both are precision tools. The two have totally different ergonomics and the Meco takes a little getting used to for some, others love it. Smith equipment in general, isn't what it was 30 years ago, but I get a feeling thats no difference for some of this group because you were probably in grade school at that time. The Henrob works but has wrong ergonomics for too many of the joints. I have one of each of the mentioned torches and use the Smith most of the time. The Henrob, however, is the best cutting torch I've ever used. The Victor or any other name brand are good torches but too big and heavy for the use. DON'T UNDERESTIMATE THE EFFECT OF TORCH AND HOSE WEIGHT ON THE QUALITY OF YOUR WELDING (That's me trying to make a point, not yelling in an angry voice). I bought my Smith over 35 years ago. I seriously doubt you'll still be using a Harbor Freight torch that far into the future. The torch supplies the actual finger of flame that creates your airplane. You need absolute control over that flame and that requires a precision piece of equipment and something made in China that sells for $99 ain't it. This is simply the wrong place to try to save a few dollars. bd +++ #13768 From: "Dan Montee" Subject: Re: Welding equipment I'm one of those that use a hybrid combination for welding BH parts. My torch is the Smith AW1 Budd mentioned. I use Kent's UL hoses, Kents TM 2000 lens and Budd's recommended magnifier lens. If I was to buy a new torch today it would be a Meco with the above acc. The Smith valves have minds of their own and the biggest nuisance is they will or won't allow a one hand adjustment depending how they feel at the moment. My new Smith gauges aren't as good as my 30 year old Victors for holding a setting. Don't forget to order the 4130 videos with the torch. They are invaluable. Dan Montee # 415 +++ #13801 From: "Bruce A. Frank" Subject: Welding equipment & a New Job I have always preferred two stage regulators, but single stage technology has gotten so good that there are few 2 stage types out there today. But you still cannot beat the stability of a two stage regulator. It happens that I just took a job yesterday as an outside sales representative for Cronatron Welding Supply. As I looked through the catalog I ran across two stage regulators. Guys, I haven't stared to work yet, won't for a month or so, and don't even know the prices. If anyone is interested I'll see what I can find out. Bruce A. Frank +++ #13822 From: tonychisum@w... Subject: Re: Welding equipment > Sams does not seem to carry the Victor unit these days out in the > Denver area. The Harbor Freight unit is $99.00 but I have not seen a > name brand unit out here for less than $200 in a while. Even saw a > store brand earlier this evening for $199. Wag-Aero has the Smith airline kit for $242.50. I paid over $350.00 for the same kit at a welding supply. You will need to order some smaller tips though, but it is still a good price. Tony C. +++ #13942 From: "Kent White" Subject: RE: Welding equipment Regulators... I use and sell a bunch of regulators. In the 4-day classes I hold, we use 3-4 sets daily with 2 torches going off each set, and 6-10 classes per year. I use Victor or equivalent quality - I know about the generics that sell cheap. The single stage regs have fallen in quality over the past 5 years, that I can tell. This is, of course, down in quality from the 60's and 70's, when regs would go for 15 years easy, if you did not pop them. This past year I finally took a deep breath and ordered the dual stage regs from Victor. Big money, like $250 each. Cough cough. Well, with two torches going on one set, they are stabile. And with only one, far more stabile than the late model units I replace every two years. I cannot recommend spending this amount of money, unless the craftsman really really wants perfectly smooth gas flow, day after day. I would rate these as truly professional pieces, as opposed to the strictly hobby quality I get for $80 -$100. Kent +++ #14116 From: Budd Davisson Subject: Re: Welding > I have seen how well everyone seems to like the Meco Midget > torch. Has anyone tried the Smith Little Torch yet? or better yet > has anyone used both and be willing to give us a comparison. I am > getting ready to buy a small torch and any input would be useful. Go back about three days and you'll pick up the answer on this. Until the Meco came along, the Smith was the ONLY torch. I have all three, Dillon, Meco, Smith and use the Smith the most because I like the ergonomics better (and I'm old fashioned), but it's an old one (had for 35 years). The new ones have had problems with their valves not being stable. We had one at the plant that drove us nuts and it turned out to be crud in the valves right out of the factory. Cleaned the valves and it worked fine. Smith is a good choice, but fire it up the minute you get it and check it to see if the valves adjust smoothly and hold their setting. If not, call Smith, raise hell and send it back. They back up their material quite well. bd +++ #14121 From: "Kent White" Subject: RE: Welding > I have seen how well everyone seems to like the Meco Midget > torch. Has anyone tried the Smith Little Torch yet? I have had one for years. I used it a couple of times, back in '91. It is ok, I guess. Dainty thing that seems fine for delicate jewelry, for which it was designed and sold. Kent +++ #14125 From: "Kent White" Subject: RE: Welding The Smith "Little Torch" is the size of your index finger and is made of plastic, anodized aluminum, and bright plated brass. The (sapphire) tip sizes are microscopic, and the "hoses" are akin to aquarium tubing. No resemblance to the Smith Airline, at all. Kent +++ #14126 From: "Kent White" Subject: RE: Welding Funny thing, the Meco is about twice the size, but much heavier, as it has no plastic or aluminum. The shape is flat and far easier to hang on to, for some. The Smith Little is round, featherlight, and must be held like a big ballpoint pen, not comfortable for doing steel and aluminum sheet and tube. One of the auto resto catalogues sells the Smith Little, though I cannot fathom why. Kent +++ #14132 From: "Bruce A. Frank" Subject: RE: Welding > When I said the Smith "Little Torch" I was speaking of one like the > attached photo I dont think any one has mentioned it yet. I have used that torch, it is considered a jeweler's torch and it is beautiful for that job, but I have not found it suitable for tube fuselage welding. In inside corners of clusters it is just not up to the heat requirement...it cannot flow gasses fast enough through the available tips to produce the amount of heat needed. With the small tips usually available with the torch high heat requires such a high flow/pressure that the flame literally tends to blow the puddle away. Not only that but when you have to use such high flow rates through a small tip induced turbulence tends to entrain air contaminating the weld puddle. Now my torch was my farther's and though the tip collection with it was complete todays kits may contain larger tips. Research it to see what thickness maximum are recommended, but remember that an inside corner will absorb 2 to 4 times the heat needed to weld equally thick material in a simple butt or lap joint. Bruce A. Frank +++ #14172 From: Benton Holzwarth Subject: Propane Torch vs. Rosebud? Received the latest Harbor Freight e- sale flier today. The $18 propane torch ("Ideal for melting ice or burning weeds. Attaches readily to propane tanks...") caught my eye. I was wondering if one might make a good alternative to running a rosebud when heating clusters. How would the economics work out for using Propane rather than O/A for warming clusters? Would the ability to run a rosebud and welding tip at the same time force me to size up to a larger Acetylene tank than I might have picked up otherwise? Would Propane contaminate the welds? Benton +++ #14175 From: "Shannon Spurgeon" Subject: Re: Propane Torch vs. Rosebud? >From past experience using a rig similar to the weed burner for heating branding irons, you could go this route, but I think the time consumed and volume of propane would make it no better than the rosebud at best. Since both acetylene and propane are nothing but carbon and hydrogen, I don't think contamination would be a factor. The weed burner would have to be turned up to a high roar, the area heated may be larger than ideal, and the waste heat in your shop would be massive. Not a problem in winter,... One other thing was that the branding irons had to be contained in a piece of about 6 inch pipe, 2-3 feet long, with a cap on the far end from the burner to concentrate the heat. Would you need a reflector around the clusters? Shannon +++ #14176 From: "Bruce A. Frank" Subject: Re: Propane Torch vs. Rosebud? If you used propane with oxygen it would work just fine though a bit slower because propane burns cooler. Trying to heat a cluster with an oversize propane torch, like the brush burner heads, just using the mixing air, could be done but would take a looong time....several minutes versus several seconds. The rosebud is a necessity in my book....though you could run that with the propane and oxygen. Even Map gas, burning much hotter than straight propane (MAP gas contains dissolved acetylene) is not quite enough to red heat strain relieve steel...unless you use oxygen. There are limits on how fast you can pull acetylene out of the cylinder but small rosebuds are up to the job on the fuselage and usually cause no problem with the cylinder. You are really not going to use that much additional gas with the rosebud. When you say "run...at the same time" are you intending to have both the rosebud and welding torch in use during the same moment? Rosebuds need to be operated at higher pressures than the welding torch. The rosebud develops a lot of heat and is cooled by the gas flow. If you try to operate a rosebud at the same regulator settings as the welding torch you'll likely have back flashes where the flame pops and starts burning inside the torch head (or worse, back in the body of the torch). This can damage the rosebud and the torch body if you don't get the gas cut off quickly. Bruce A. Frank +++ #14180 From: "Shawn Burns" Subject: Re: Propane Torch vs. Rosebud? As was earlier stated, I don't think a propane flame would contaminate the weld. If you had a propane torch clamped to be directed at a cluster, it would seem logical that it would help to relieve any stresses that might be induced in the oxy/acetylene welding of a joint. Here is a question to ponder- could you avoid the complications associated with TIG welding a cluster of 4130 (IE. a zone of inbrittlement/cracking around the joint) tubing by setting up pre-intra-post heating with a propane torch clamped focused on the cluster. This would avoid the major caveat that is associated with TIG welding 4130 in aircraft structures- a narrow zone of rapid heating and cooling of the joint and subsequent stresses due to the induced variations in the crystaline structure of the adjacent material. I have only rudimentary experience with TIG, but this does seem to be a logical solution. Propane is relatively cheap and it would be easy to fashion a clamp/stand to hold a #1 bottle with a heating tip attached. Any ideas or comments? Shawn Burns +++ #14192 From: Benton Holzwarth Subject: Re: Propane Torch vs. Rosebud? > When you say "run...at the same time" are you intending to have both > the rosebud and welding torch in use during the same moment? > Rosebuds need to be operated at higher pressures than the welding > torch. I thought I'd read on this list that one technique was to play the rosebud on the back side while welding up the front. (I suppose I could have added that the propane torch could spare me buying a second set of regulators, as one of it's pluses.) They claim a 3000-deg flame from the burner, but of course, people make all sorts of claims. Is the technique to warm the cluster with the rosebud, then quickly switch to the welding tip and reset the regulators? It's been a long time since I did any welding (and not much then), but my impression was that the metal would cool down pretty quickly after the rosebud was pulled away. (Cool down relative to welding temp, not relative to burning the &%$#@$% out of my hand temp.) I thought the idea was to get the entire area warmed up, so that the cold tubes didn't draw heat away from the weld-area as quickly, and thought one of these Propane burners might do the trick. In terms of contamination, I was thinking more in terms of whether a straight Propane w/ air flame would be 'carburizing'. If I have to go to MAPP gas, or Propane w/ Oxygen, that would seem to complicate the thing to the point that just using O/A and a rosebud makes sense again. Don't mind me, I was just thinking out loud -- while fully realizing these side experiments are part of what's keeping me from making forward progress on #421. I'll get back in my box now. Benton 17jan03 +++ #14195 From: Russell Bell Subject: Re: Propane Torch vs. Rosebud? Here's a better option on propane torches. Look at this site: http://www.airarc.com/products/gasapp/victor/turbo.html and then look at the hand torch (fifth item down, right side). This is a plumbers hand torch, screws on a standard 1 lb. propane or mapp gas bottle, and will produce twice the heat of a bernzo-trashic. The arm swivels 360 degrees, and you can set it on the bottle, rotate the arm to a position, and it will stay there. It will develop about 1400 degrees on propane in open air and 2600 on Mapp gas. It is available at most HVAC suppliers. It is a Victor turbo-torch, so it is both quality and pricey. Expect to pay 50-60 bucks for the torch. It should, however last a lifetime. I'm a plumber, use mine frequently on small stuff, it rides in a tray in the truck and gets bounced around, and in twelve years has never given any trouble. Russ Bell +++ #14360 From: "Kent White" Subject: RE: Didn't think that one all the way through... Weld test #17, trying to hack off a bracket snuggled safely in some upper corner. Do I hear "smokewrench?" Kent +++ #15142 From: Del Rawlins Subject: Re: Strut top end link guidance? ... Another tidbit for anybody who is welding up the small parts; I have a couple of large magnetic welding angle clamps and a steel welding tabletop. It's a great combination because by monkeying around with the clamps, I can arrange the parts at whatever angle is needed for a particular weld. I also bought a really cheap drill press vise that is sometimes useful for holding items to be welded. The nice thing is, using any of these items I can just fix the ground clamp to the table itself and forget about it. -- Del Rawlins +++ #15277 From: Del Rawlins Subject: fuel tank distortion Please excuse this outburst of on topic material, I'll try to keep it to a minimum. 8^) I'm hoping Kent White and some of the other more experienced welders can answer this question. A topic that has come up in the past has been distorting the aluminum fuel tanks during welding, particularly around the filler necks. One thought that occurred to me tonight, is that I used to see advertised in the Eastwood catalog and other places, heat sink putty meant to control such distortion. Does that stuff actually work, and would it be worth using for this application? -- Del Rawlins +++ #15285 From: Budd Davisson Subject: Re: fuel tank distortion I'll have to let Kent answer this specific application but for years I've made a thick, wet paper mache type glob of stuff and stuck it on sheet metal when welding and it works great. I'm still using some I mixed up years ago out of asbestos piper wrapping (remember that stuff?) that I just re-wet and remold. Everything in Eastwood's catalog is wildly over priced so it's probably available elsewhere, but you could even build a dam out of wet sand and do the same thing. fyi--I started using this stuff in college as a blob on the end of a heat sink I machined to slide inside Mauser bolts when cutting, reshaping and welding the bolt handles for scope clearance. It's an old gun smith's trick. bd +++ #15301 From: Del Rawlins Subject: Re: fuel tank distortion >Everything in Eastwood's catalog is wildly over priced so it's >probably available elsewhere, but you could even build a dam out of >wet sand and do the same thing. That is true, nearly everything Eastwood sells is available elsewhere for less. The trick is, you have to know where and their major appeal is that they put so many handy things into one catalog. I wouldn't buy clecos from them at their prices because I can get them cheaper someplace else (that I would probably be ordering from anyway). But I've bought a number of items from them that I haven't seen for sale anywhere else, so it is the service of finding the stuff you are paying for. -- Del Rawlins +++ #15735 From: "Vuxton, Christopher" Subject: Using Propane for cutting I had the privledge of touring the Newport News Shipyard last week. You've gotta wonder what are people thinking about taking on the US Navy when you are standing next to the new USS Texas (latest Virginia class SSN)that is being built at Newport News. Hugh ring sections about 35 - 40 ft tall completly plumbed and ready to be welded to the next section just like a modular home. 12 missiles and 28 torpedoes if you go cocked and locked. But on to the question. I noticed that they use propane to cut steel. Does anybody have experience with this? Chris +++ #15743 From: "Bruce A. Frank" Subject: Re: Using Propane for cutting Torch cutting is a chemical process using a jet of oxygen to consume the heated steel in the area of the jet...called the kerf. Any fuel gas will work reasonably well. Propane takes longer to heat the steel because it's combustion temp is lower. Where cost is important in a production situation propane may be a reasonable alternative to acetylene. You shouldn't braze with it. Once the kerf is started if you have a steady hand you can actually cut off the fuel gas. I have seen it demonstrated dozens of times. If you intent is to use Propane for cutting and pre/post heating go for it. If you intend to weld with it you will get an inferior weld...meaning the steel will become contaminated during the weld process. Also be aware that you cannot use the same equipment for Propane as you do for acetylene. Some parts will work, but not all. Bruce A. Frank +++ #15751 From: "Shannon Spurgeon" Subject: Re: Using Propane for cutting My uncle has used propane for cutting for over forty years. Sears brand torch that is nearly impossible to get tips for now. Cuts ok, very frustrating trying to braze with it - just doesn't seem to get hot enough. Shannon +++ #15812 From: "Mark Conover" Subject: Welding larger items with the Meco Midget Torch Some of you, the now famous Erbman for one, are using the Meco Midget torch. From what I have read, it sounds ideal for aircraft work. What are its limitations with regard to welding larger structures? Can it be used for "meatball" welding, such as building the requisite welding cart? By the way, I signed up at my local technical community college for its Welding I class (as well as a machine shop class). Thanks for your comments, Mark Conover, #502 +++ #15833 From: Russ and Penny Erb Subject: RE: Welding larger items with the Meco Midget Torch > Some of you, the now famous Erbman for one, are using the Meco > Midget torch. What are its limitations with regard to welding > larger structures? I haven't used the Meco on anything but the airplane so far. I did use my Henrob 2000 to weld up a couple of grills built from 1/8" thick angle iron, and with the large welding tip that was pushing its capabilities. Anything larger would be tough. I don't think the Meco would do any better on large parts. If you want to do that, you might need a bigger torch or a buzz box. Russ Erb +++ #15839 From: Del Rawlins Subject: RE: Welding larger items with the Meco Midget Torch > If you want to do that, you might need a bigger torch or a buzz box. I find that a buzz box is pretty much required for anything over 1/8" thick. Even if you can weld heavier metal, you rapidly reach a point where it is a lot cheaper to burn electrons than welding gas (though for whatever reason I'm determined to use lots of both on welding the thin stuff). A basic arc welder costs what these days, a couple hundred bucks? My dad bought one made by Miller back in the early 70s that is still going strong. It's pretty hard to go wrong buying one. -- Del Rawlins +++ #15845 From: Budd Davisson Subject: Re: welding bigger stuff If money isn't tight and you don't plan on going over 1/4", get a MIG. You'll never regret it. With the smaller MIGs you can do 1/4" and over but it takes multiple passes which are obscenely easy. At the same time, I routinely weld 22-24 gauge (about .030, I think) with no problem. Lots of flexibility. Stick welding is really hard on thin stuff for everyone except Kent. Still, I agree with Del: my buzz box has been with me going on 40 years and hasn't hiccuped once. bd +++ #15846 From: "Russ Kaye" Subject: RE: Re: welding bigger stuff Depending on your application when welding 1/4" or over with MIG you might consider pre-heating the base material. Russ Kaye +++ #15849 From: Budd Davisson Subject: Re: Re: welding bigger stuff > Do you think a Meco Midget could handle the task of building the die > that is referenced in the July 1998 Beartracks? > > Here is the photo: > > http://www.conotech.com/public/av/bearhawk/jul9821.gif > > I appreciate your guidance, > > Mark Conover If you get some Eutecteloy (I think that's the current name for it) high strength brazing rod from Eutectic, you can braze that together as long as you clean all the mating surfaces really well cleaned and you heat all the way through so the rod "wicks" into the gaps. Normal brazing rod would probably do it just as well. The Meco will definitely handle that. bd +++ #15851 From: Del Rawlins Subject: Re: welding bigger stuff > Do you think a Meco Midget could handle the task of building the die > that is referenced in the July 1998 Beartracks? Not if you are planning to weld it. I did mine with the aforementioned 30 year old buzz box. Built the press that goes with it, too. It's amazing how much fabrication capability results from $400 invested in a taiwanese bandsaw and a buzz box. I'd be interested to find out if brazing would hold up under the force of a hydraulic press. I wouldn't want to be nearby while it is being tested, though. -- Del Rawlins +++ #15877 From: Budd Davisson Subject: Re: Another welding question... There is no such thing as a cheap welding rig. It won't work as well as it should and you'll end up spending more money for another one, so it costs you more in the long run to go cheap. Welding with torches that don't have high quality is not only frustrating, but considering that your life depends on the welds, it can be damn dangerous. Don't cut corners: go Meco or Smith