+++ #397 Subject: Tail Wheel Steering Yoke From: Rodney Smith Sheet 21 of the plans shows a 3/4" Tube about 2 1/2" long welded inside the bottom of the 7/8" rudder post. The plans say inside to fit tail wheel steering yoke. So far I've found a couple places to buy these steering yokes or rudder arms as they are also called. They all have 3/4" posts so aren't going to fit per plans. If you mount the steering yoke directly in the 7/8" rudder post it will be a sloppy fit. Anyone have a soure for a steering yoke with a smaller diameter post or have another idea? +++ #398 Subject: Re: Tail Wheel Steering Yoke From: Float-by Shooter > Sheet 21... Would it be reasonable to splice in a thicker piece of 7/8 tubing, and ream it out to fit the rudder arm? +++ #751 Subject: Tail Wheel Leaf Spring From: William & Delinda Johnson I am new to the group so here is a quick intro. Bearhawk 023 wing ribs are formed, spars built, and fuselage welded. Just completed the landing gear shock struts today and will install this weekend. I need a tail wheel leaf spring. Aircraft Spruce sells leaf springs but I am not sure which to buy. Any recommendations? Also, Bob mentioned in one of the newsletters he might publish how to build a tailwheel and leaf spring. Mike Meador, is that still planned? Also, Mike please send me your e-mail address to wjohnso-@fuse.net. I will send you digital pictures of my progress. +++ #752 Subject: Re: Tail Wheel Leaf Spring From: budd davisson an unsolicited comment on tailwheel springs: If anyone is serious about turning their airplane into a "dirt monkey" (that's what we call bush planes here in Arizona) they might consider a tapered rod tailwheel spring. A continual source of aggravation in Super Cubs and Huskies is the tailwheel attach area of the fuselage which eventually developing cracks if continually flown on rough surfaces. This is because the leaf spring transfers side loads so readily allowing rocky surfaces to put shock loads into the structure. A taper rod spring bends sideways and won't transfer the loads. Just a thought. +++ #754 Subject: Re: Tail Wheel Leaf Spring From: Tony Dean I like this idea. How do you go about building one? Is there a standard sizing and possibly a parts source that could tell us how large it should be for a BH and other designs? +++ #755 Subject: Re: Tail Wheel Leaf Spring From: Tim Anderson I seem to recall looking at cessna 180/185 tail wheels/springs and seeing what looked like a round tube-type spring. It was fairly long and did not have much bend (as compared to many leaf springs). The mode of mounting would be different than a leaf spring. This may be a type of tappered rod application. One could easily find replacements and tail wheels. +++ #756 Subject: Tapered Rod....Tail Spring From: Tim Harmon Lange...of Langeair Machining, in Oregon makes machined tapered Rods ala all the RV-3-9's and many TDragger types....I have one that Harmon made for a Whittman Tailwind, it will eventually go on my EA-81 powered Midget Mustang. It cost $45 about 6 yrs ago. I have seen a link somewhere out there either to a Web or possibly an Email contact......check Van's website might be a link there. +++ #757 Subject: Langeair Machining...Contact # From: Tim For anyone interested; What Budd said re: side loads, makes perfect sense...Tail rod price upon checking, I paid $75.00...5yrs ago Below is the last Number I have for Harmon...I think this is the number I used to call about 2yrs ago, when Dean and I flew his Spam Can, down to Scappoose Oregon, to see Harmons Montana Coyote project....that is the flight where we got cut-off by a Navy P-3 Orion coming from or 9 o'clock, climbing out of Whidbey NAS...The 4 engined mother didn't see us....It doesn't get much closer than this, bloody miracle we missed his wing tip vortices. Langeair Machining's Last contact number.....(503) 397-1478 Oregon Dean's Coyote project (think he is giving it another name) has undergone some good improvements. He totally made new landing gear, getting rid of the that forward canting gear (torque factor hard on the longerons) and re-inforced the cabin structure....think he said overall about 100+ hrs of additional welding. Dean's many mods include, a kewl set of fiberglass tanks, fiberglass flap/aileron skins, Aluminum (wing) leading edge, a trim system idea from his 25yrs of building/driving race cars.....& much more......Con's> Bearhawk will pass him while still in 1st gear....Coyote/Mountain Eagle wing is an 105 mph airfoil....not a Riblett +++ #758 Subject: Tapered Rod....Tail Spring From: Russ Erb For what it's worth, I looked at a picture of a buddy's Cessna 180. It uses a tapered rod tailspring. I can definitely see the benefit of springing the side loads as well. Now we just need a way to attach it to both ends. +++ #759 Subject: Connecting Tapered Rod....Tail Spring From: Tim Attaching the Tapered Rod Tail Spring; The tapered tail spring looks just like a minature of the RV main gear legs.....just a smaller copy. The threaded end has a shoulder that is stepped down, to accept the tail wheel housing. The fuselage end fits into a socket like the Van's RV main gear does. Steve Whittman designed this type of socket gear for his T-winds....... Budd can correct me here, I think Steve sold his design to Cessna for production rights....That's when the Leaf spring vanished and the faired tapered rods arrived....... +++ #760 Subject: Re: Connecting Tapered Rod....Tail Spring From: budd davisson Tim is correct about Steve's patent on the spring. I'd think if there was enough interest, Harmon Lange would make them. However, be advised, designing the spring is more complicated than it looks because the diameter and taper really effect the rebound characteristics. I've flown some on Pitts that want to hop a little. Probably the best thing is to simply copy a C-180. It'll probably be a little bit stiff but better stiff than too light. Another advantage is they put the tailwheel back a little further making the wheel base longer and the airplane a little more stable, which the airplane doesn't need, but it helps. +++ #824 Subject: 023 Progress and Lessons Learned From: William & Delinda Johnson Anyway, related to tail leaf springs, after much discussion and some consulting with Bob, I have decided on purchasing a PA25 tail spring from Univair (part number PA25TWS1) for approximately $90. I decided on the PA25 because Bob recommended two leafs all the way to the tail wheel bolt. Taper rod was attractive but with the Scott tailwheel, side loads should not be a big problem - it will go to full swivel if a major side load occurs. +++ #1017 Subject: Home Brew Tailwheel From: robert gaddy In the Jan Bear-Tracks Bob writes "I am using a tail wheel of the same construction that I designed and built for the prototype with a few modifications to use a 10 inch O.D. tire ..." Has Bob made this design available? I see no mention in the newsletter index and don't remember it being on the plans. +++ #1045 Subject: Tailwheel Plans From: Mike Meador > Mike, do you know when/if Bob is going to publish the plans for his > homebuilt tailwheel? I have been working on Bob to draw up a set of plans for his tailwheel. He has not decided to do it yet but I get the impression that he will eventually. I will let you guys know when he makes up his mind. One thing about the tailwheel is that it is applicable to many different homebuilts and can be sized to fit just about any application. +++ #1050 Subject: Re: Tailwheel Plans From: Float-by Shooter > I have been working on Bob to draw up a set of plans for his > tailwheel. He has not decided to do it yet but I get the impression > that he will eventually. I will let you guys know when he makes up > his mind. Well, if he isn't going to draw up plans for it, that sure wasn't very nice of him to dangle that particular carrot in front of our faces! 8^) > One thing about the tailwheel is that it is applicable to many > different homebuilts and can be sized to fit just about any > application. I'm wondering if it would be possible to incorporate a locking mechanism which would lock it in steerable mode, and unlocked it would be full swivel? I don't know if such a beast is even available in a size suitable for the Bearhawk, but it might be handy. I think I'd have a lot better chance of building that into a homemade tailwheel than modifying a factory unit. I know it is more complexity but spring loaded it should only require one small cable. Or would it not be worth the effort? +++ #1057 Subject: Re: locking tailwheels From: budd davisson I fly a lot of airplanes with locking tailwheels and I find them to be a pain in the butt for taxiing and they don't add anything to ground handling worth measuring. Worse than that, if you lose a brake, you usually lose the airplane, when it slows down. The Bearhawk absolutely doesn't need it. It's directionally stable enough without a lock. If you do decide to go with a Haig style locking wheel, at least don't use a separate lock. Hook the cable to the stick ala late T-6 or Mustang, so the wheel is unlocked when you push the stick well forward and it's locked in any other position. +++ #1062 Subject: Re: locking tailwheels From: Float-by Shooter > I fly a lot of airplanes with locking tailwheels and I find them to be > a pain in the butt for taxiing and they don't add anything to ground > handling worth measuring. Worse than that, if you lose a brake, you > usually lose the airplane, when it slows down. The Bearhawk absolutely > doesn't need it. It's directionally stable enough without a lock. I'm not talking about one that would lock straight ahead, I can see where that would be a pain in the butt. I was just thinking about something that would be steerable, and not go to full swivel unless I manually unlocked it (for parking or maneuvering on the ground). I figured it might be a bit more positive than a regular tailwheel with the automatic full-swiveling feature. Chances are I probably won't bother when the time comes and I want to get in the air; it's real easy to think about these things now when I am in no immediate danger of having to fabricate them. I'm not even sure if such a contraption would be feasible to make, but thanks for the advice. When I finally get a chance to get some tailwheel time I will probably decide whether or not it would be worth trying. +++ #1124 Subject: Tail wheel/rudder springs From: Tim Anderson I send out an email to the group a week or so ago regarding the difficulty in connecting/disconnecting tail wheel/rudder steering springs. No one replied. Therefore, I must be the only one that has fought this battle. Maybe there is a spring compressing tool I'm not aware of. +++ #1125 Subject: Re: Tail wheel/rudder springs From: budd davisson I've always just pushed the rudder to one side while holding the tailwheel centered. Was I doing wrong? It was either do it that way or, as I'd do it back in Nebraska, just get out a big pair of dykes and say to hell with it. +++ #1126 Subject: Re: Tail wheel/rudder springs From: Tim Anderson Well, that's what I have done also. Maybe it's a easier two-man job. Putting the shoulder into the rudder, while kicking the tail wheel the opposite way with the foot, while trying to hook or unhook the connecting chain ring loop. Everything I built, I try and design for single-person operation. Wing mounting is one of the few problems I haven't been able to conquer as a single-man operation, but give me time on that one. One needs to tinker you know. EUREKA - I have an idea. Where is my patent application notepad. +++ #1127 Subject: Re: Tail wheel/rudder springs From: budd davisson My life has been a quest for one-man operations because I'm always working alone, including sheet rocking ceilings. With the proper procedurs its no sweat. On tailwheels, I'd just take a huge "C" clamp and clamp two lengths of 2 x 4 on either side of the wheel, so I could kneel down behind the wheel sith the lumber going between my legs to where my feet could grab it behind me. They'd have enough mechanical advange to hold the wheel while I moved the rudder with one hand and unhooked the spring with the other. +++ #1751 From: Rod Smith Subject: [Bearhawk] Tailwheel$ I was in Anchorage the other day and stopped in an air parts store to pick up a small amount of tubing (yes I screwed something up). On the counter were a couple Cessna tailwheel units, designed to fit the tapered rod spring. One was normal size and the other had an oversize fork and was fitted with a 5.00x5 tire. I thought boy that would be just the ticket for the Bearhawk. Then I made the mistake of checking the price tag. $1750! and the smaller one was only 300 less. Please! someone design a tailwheel unit we can build. Otherwise I will try to find a used Scott and do the Gar-Aero mod that puts a large fork and big fat tire on it. I've got lots of time to look. +++ #1766 From: budd davisson Subject: [Bearhawk] Re: Tailwheel$ Rod, Relax on the tailwheel thing. Bob has a design on prototype two that will do the job and builds fairly easily. By the way, has anyone taken notice of the fact that Bob built his own propeller blades for the Hoffman hub on P-II? He does everything himself. When I saw him on Monday I forgot to ask how his crop of beer cans are coming. We joke about it on the e-group, but I think he's serious about it. +++ #3967 From: budd davisson Subject: Re: Fuselage Questions Tubular Tailwheel spring Go look at a C-180. All you need is a tapered rod spring that sockets into heavy wall tubing that has brackets welded to it that pick up the existing tailwheel spring bolts. The taper rod spring isn't necessary unless you're working rough, especially rocky, fields. +++ #4440 From: Russ Erb Subject: Identify your tailwheel early! A week and half ago I made the hour trek south to Pearblossom to check out Pat Fagan's progress. He's got the wings done and the fuselage frame welded up. The fuselage is at the classic 90%/90% stage--It looks 90% done, but has about 90% to go. All of that fitting out takes a long time. He'll still be done before me. I'm hoping he'll be nice enough to give me some time-in-type before my first flight. A couple of items that came up in our discussions: 2. The plans for the tail end of the fuselage are set up for a tail wheel spring 1-1/2" wide. Pat found that most tailwheels now available use a wider spring (1-3/4"?). The learning point here is to identify what tailwheel you're going to use so that you can adjust as required. +++ #4442 From: "Float-By Shooter" Subject: Re: [Bearhawk] Identify your tailwheel early! > 2. The plans for the tail end of the fuselage are set up for > a tail wheel spring 1-1/2" wide. With all the discussion regarding tailwheel springs that took place some time ago, I'd be interested to learn whether the kits will be set up for a leaf spring pack or a Cessna 180/185 type round spring. Has anybody actually pursued adapting this design to the Bearhawk? +++ #4445 From: Ken Beanlands Subject: Re: [Bearhawk] Identify your tailwheel early! I seem to remember that a there is an adapter plate to switch from a 1-3/4" tailwheel to a 1-1/2" spring. It seemed to me that I saw a thin plate with two 1/8" spacers on either side that fit between the spring and the tailwheel. My 8" pneumatic Matco (impressive little unit, BTW) has the ability to take either spring in the way that the mount is shaped. In other words, if you use the smaller spring width, you should be fine. Hope this helps. +++ #4447 From: budd davisson Subject: Re:Kit Seats, tailwheel springs, windows To answer the questions asked: The initial batch of kits is going to be "as per plan," which means a leaf tailwheel spring and, as part of the 51%, no seats. +++ #4692 From: pfflyerz@c... Subject: digging out from under the pile of postings Like Russ said, my Scott tailwheel is designed for 1 3/4 inch springs. I made an adapter for 1 1/2", then tried bending some 1 1/2" material ala Bingellis. Having no luck with that technique I made a wooden block the shape I wanted and went to two spring shops to have one made. They both told me no one sells 1 1/2 inch spring stock anymore, but I got a great spring made from 1 3/4 inch material. Be sure and check into availability before making and welding a 1 1/2" bracket to the tailpost. +++ #5609 From: bcox@a... Subject: Tailwheels An airplane question for Bearhawkers. I picked up a Maule solid tailwheel at an auction (P/N SFSA), and it works with the 1 1/4" leaf spring. The unit looks pretty good, and is steerable and full swiveling. Does anyone know if this unit is beefy enough for the Bearhawk (provided I don't do any serious backcountry landings)? Thanks, Brian Cox, #478 +++ #5610 From: "vic" <11acs@g...> Subject: Re: [Bearhawk] Tailwheels I took the Maule off of my Aeronca & put on a Scott. Made a world of difference. Quieter, smoother, and I could swear that it has more traction for steering probably because it has a tube. Vic #431 +++ #5612 From: Ken Beanlands Subject: Re: [Bearhawk] Tailwheels I have a similar tailwheel. They seem to be an OK tailwheel but due to the age of mine, it's easy to see where they wear. There is a brass or copper bushing inside the pivot barrel that wears and will cause a shimmy. Also, the locking pin (on mine) was frozen in the swivel position (not something you'd want to happen in heavy winds. I don't know what the age of the unit was or how long it had been in service, but these items were noted. I decided to replace it when a kind sole on the Piet list offered an 8" pneumatic Matco tailwheel for sale at a good price (SteveE, I'm sure the 6" looks better ;-). THis unit appears extremely solid and simple in it's action. Even new from a supply house, they are pretty cheap. It uses the springs in the tailwheel actuation wires as part of the automatic swivel action. It's really slick. SteveE, how did the 6" work on the Piet? The best tailwheel out there is unquestionably the Scott. This is probably why you will find them on most production planes and many kit and homebuilts. However, they are also the most expensive. Most of the people I've talked that owned Maules have switched to Scotts. Ken Beanlands B.Eng (Aerospace) +++ #5616 From: Budd Davisson Subject: Re: [Bearhawk] Tailwheels A note about Maule tailwheels, past and present: for years I bitched incessantly about the Maule tailwheel that Pitts were certified with. Basically, they were an 80 time change item for me. The wheels would give out and the mechanism would loosen up enough to start shimmying and you couldn't adjust it all out. I went to a Scott 2000, which was a much better unit (and twice as expensive), but then found I couldn't get the best solid tire, the Goodyear. The Generals only have four locating nubs, rather than 11, as on the Goodyear, so they spin off the hub without wrning. About 18 months ago I mounted one of the Maule "big softy" units, which appears to be exactly the same as all the other solid Maule units except the tire is 6", rather than 4" and is a little softer feeling. In the past, I used to think the reason old BD Maule didn't make it into heaven, when he died, was because he invented that damned tailwheel. Now, I'm changing my tune. I'm getting as much as 200 hours or more out of the new units, which had some QC problems with the really early ones but are now fixed. I think one of the "big softies" would work on a BH, but I sure wouldn't go for the smaller ones. If you're serious about it, I'd go for a Scott 3200. Considering the rediculous price tailwheels cost, there's a lot to be said for welding one up, as Bob did. 'Pretty hard to beat a Bob Wheel. bd +++ #5617 From: Brian Cox Subject: RE: [Bearhawk] Tailwheels Thanks everyone for the advice. I'll keep it in my inventory, and if I get a smokin' deal on a used pneumatic, Maule, Scott,or Matco...I can "upgrade". It'll be quite awhile before I need to get the fuselage on the gear - I'm just finishing my rib form block and routing templates. Brian Cox, #478 +++ #5620 From: Budd Davisson Subject: Re: [Bearhawk] Tailwheels > Is the "BobWheel" detailed on the plans? What sheet? Don't think so. There's a detailed photo of it though in the BH 260pirep on airbum.com. bd +++ #5621 From: Steve Eldredge Subject: RE: [Bearhawk] Tailwheels I like the 6" on the piet. I have abused it pretty good and it still works fine and swivels nicely. I am at about 200 hours and the tire has got another year or so... I wish ken would send me back my 8" Matco, :) (kidding really) I'll probably buy another one for the bearhawk. They are cheap, simple and rugged, and will adapt to 1-1/4" and 1-1/2" springs. Not sure why they aren't more popular. Steve E. +++ #5624 From: Steve Eldredge Subject: RE: [Bearhawk] Tailwheels > Does the 6" have the reinforced nylon wheel and solid rubber > tire? The six inch has the reenforced nylon wheel with a rubber tread. Steve E. Check out www.matcomfg.com for the whole product line. The site is kind of dated, but the info is still good. SE +++ #5638 From: slester@m... Subject: Re: Tailwheels I can verify your comment about traction. The first Taylorcraft I flew (and in which I got my endorsement) had a solid tire and I flew it only on grass. The second one had the pneumatic Maule, and I flew it from pavement. Took me a couple of tries to stop darting from side to side on the runway... I don't think you'll like the Maule on a Bearhawk. In my experience, the steering arm gets loose in the pivot axle, contributing to a lot of shimmy. +++ #5641 From: "Tim Anderson" Subject: Re: [Bearhawk] Tailwheels The "Bob-wheel" is hard welded (cable attachment arms to the pivot) isn't it? ie.. it doesn't have a release mechinisum to fully swivvel when needed....Anyone know? I didn't take note of it's operation at S&F last year. I seem to recall a comment sometime back that Bob was going to describe his tail wheel construction, but I haven't seem any info. I switch from a solid maule to a pnematic tired maule and liked it...but at Kitfox speeds it doesn't take much of a high speed beating. Tim #398 +++ #5642 From: Budd Davisson Subject: Re: [Bearhawk] Tailwheels Re: Swivel of Bob Wheel It's interesting that I've flown the airplane three times, twice in the last year, and I can't tell you whether the tailwheel unlocks for swivel or not. Both of the last times, I took it out of a parking spot and taxied for takeoff, etc, but was never in a situation that needed a swivel. It seems to me, I've seen Bob pick up the tail to park it. In looking at the photo of it in Airbum, I don't see how it could swivel, although I can think of a relatively easy locking mechanism to let it swivel. bd +++ #5648 From: Russ and Penny Erb Subject: RE: [Bearhawk] Tailwheels It swivels. To wit, see following exchange from Mike Meador on the Bearhawk CD. Russ Erb #164, Edwards CA August 2000 I can't stand it any more. Studying the pictures I took of the tailwheel of Proto II, between the steering arms (connected to the springs) on the tailwheel, it appears that there is a tube pointing straight back with a cotter pin through it vertically. Just what is the purpose of this tube? Russ Erb #164, Edwards CA Russ, I'm glad that I checked my e-mail before I left for the weekend - I wouldn't want you to go postal waiting for an answer! That tube contains the spring and the pin that lock the tailwheel in steer mode. On the bottom of the tube, away from the cotter key, there is a slot about 1/2" long . This allows another pin that is welded to the first pin to ride on the cam and push the whole shebang out of steer and into swivel. Later - Mike +++ #5748 From: "Bill Cox" Subject: Re: [Bearhawk] Tailwheels I talked with Bob about the Bobwheel at Sun n Fun. The main holdup on the drawings is a source for the wheel. In true homebuilders fashion Bob used a wheel he had on hand that is not readily available. He said he will supply the drawings if he can source a good wheel. I notice there was a lot of talk about tailwheels while I was away. My two cents --. If I could find the Scott 3200 at a reasonable price I would use it. I have the 6" Maule with the soft solid tire on my T18 and my experience is about like Bud's, 200 to 300 hundred hours per tire. We are landing at a much higher speed than the Bearhawk, but with less weight. At 800 hours no other rebuilding of the assembly has been required. I think that wheel is a little small for the Bearhawk. I have the 8" pneaumatic tire Maule (SPFS8?) on my Pacer and in 400 hours I have only lubricated it. No shimmy! The spindle bushing must be replaced if it gets any slop and there must be a slight rake on the spindle or it will shimmy. All that being said I bought a new Maule tundra tailwheel at the parts mart at Sun n Fun. It is a heavier version of the wheel on my Pacer. When Bob offers the drawings for his wheel I will probably build it for comparison to the other wheels. I also found an almost new set of Clevelands and a PA 25 tail spring for the Bearhawk. Bill Cox #303 +++ #5749 From: rsmith@a... Subject: Wheel alternatives Good going Bill on finding some Clevelands. That was on my short list of used items I hoped in vain to find at Sun&Fun. Some alternatives to Clevelands that I saw at Sun&Fun are new 6.00x6 wheels by Grove Aircraft. They looked like they are very high quality. Unfortunatly they are not a lot cheaper than new Clevelands. Also Murphy aircraft is now making 6.00 x 6 wheels. I couldn't ever find someone to give me an exact price but they are in the $400 range including 2 brake calipers per wheel so may be quite a bargain. Bob advised not spending more than $200 on used Clevelands but I dont know how realistic that is, he obviously is a much better scrounger than I am. After not finding a suitable tailwheel there I am going to make an offer on a well used Scott 3450 set up for a round spring that is in a shop in Anchorage. If I get it I will buy the Gar Aero kit that includes a larger yoke and 10.5 x 5" wide wheel. Kevin Kimball of Pitts model 12 fame spent some time telling me how to go about sizing a spring for the Bearhawk, he uses a solid round spring on the Model 12. Rod Smith #246 Wasilla, AK +++ #5751 From: "Bill Cox" Subject: Re: [Bearhawk] Wheel alternatives That Murphy wheel sounds interesting. The wheels I bought are a single caliper wheel. I will start with them if I don't find something better while I'm building. I think $200 would be a rock bottom price. Shopping the past 2 years I've seen plenty in the $400 to $600 range. Will the round spring for the Bearhawk be smaller than the one on a 180? Bill Cox #303 +++ #5752 From: rsmith@a... Subject: Re: Wheel alternatives I'm not sure what the size is on a 180. The spring on my neighbors 185 tapers from 1 1/4" to 1" at the tailwheel. I for some reason always had thought that they were solid until I saw one that had been cut. The tailwheel I may buy will take a 7/8th in spring. I'm thinking of going with a solid smaller diameter spring and using a bushing at the tailwheel. Haven't done the calculations yet for sizing. The price of used Cessna tail springs has deterred me from trying to modify one of them. +++ #6490 From: "Tim Anderson" Subject: Bob wheel plans Just got the "Bob wheel" plans...made a very quick study of them (few minutes). I'm curious if anyone knows if the wheel will go to full swivel when sufficient side load is applied, such as when attempting to make a tight turn by locking one brake? (a very handy feature for doing 180's on the tight runway/taxiway) Or does one have to relieve spring pressure by hand pulling the small spring plug..say when moving the tail around on the ground by hand. Tim #398 +++ #6491 From: "Dan Montee" Subject: Re: [Bearhawk] Bob wheel plans I assumed that was what the cam and bushing accomplished. If not, I think we'd have a finger biter if you tried to pull back on that AN 3 bolt that rests on/near the cam. Dan Montee #415 +++ #6492 From: "Bill Cox" Subject: Re: [Bearhawk] Bob wheel plans I haven't seen the drawings yet, but Bob told me it is full swivel. +++ #6493 From: Budd Davisson Subject: Re: [Bearhawk] Bob wheel plans Although I can't say for sure, I think it unlocks. I taxied all over both Winterhaven and Oshkosh with the airplane and I don't remember anything limiting it's steering, although I don't remember having occassion to force it to turn that tight. bd +++ #6494 From: Mike Subject: Re: [Bearhawk] Bob wheel plans It is full swivel - No problem putting it in the hangar or pivoting on one wheel in taxi - it works great! We just got back from the Virginia State Fly-In - Had a great time and even had a few surprise Bearhawk builders show up! Later - Mike +++ #6497 From: "Tim Anderson" Subject: Re: [Bearhawk] Bob wheel plans After further careful exam of the "Bob wheel" plans, I concur. The oval shaped cam at the top does the magic with the bolt/plunger. Pretty amazing and crafty, that Bob is. He even included a material list. Tim #398 +++ #6500 From: Benton Holzwarth Subject: Re: Tires/wheels > I was just passing on dimensions of commonly available 6" > tires. Not two out of one hundred reading this really need any > thing bigger than a 8.50 and 85% of those reading this would > probably be fine with 6.00 x 6". Joining the thread late -- working through some old posts... I'm told the larger tires are also more difficult to control, ground-loop wise on pavement. I'm considering burning a set of smaller tires while I'm learning the new plane. Then bump up the size as the skills improve. Also, grass is not only easier on the rubber, it's more forgiving of technique. If you can train on grass, great, but do know that pavement landings will be sticker. Benton 12jun01 >>> 2mar02 #7686-9153 +++ #8482 From: "rodsmith52" Subject: 10" Tailwheel I am building Bob's tailwheel and need a 10" wheel that is used on the Scott 3400's. I so far haven't been able to find just the wheel either new or used. Any suggestions? Rod Smith #246 +++ #8483 From: Budd Davisson Subject: Re: [Bearhawk] 10" Tailwheel If I was building a serious rocky-surface tailwheel, I think I'd modify Bob's drawngs for a 500 x 5, or maybe even a 600 x 6. Does this make any sense? Plus they are a lot more available and probably much cheaper. When I was bashing around in the Sherpa, the one thing i noticed most was that few stock tailwheels are up to serious bush work because of the rocks. Of course, if you're doing that kind of flying, you already know that. Most of us will never see those kinds of landing sites. bd +++ #8486 From: "rodsmith52" Subject: Re: 10" Tailwheel My plan is to use a nylon spacer between the wheel halves to go with a 5" wide tire. It is not quite as tall as a standard 500 x 5, 11" versus 14". The tires and tubes are available in Anchorage but not the wheel halves. Even Gar-Aero in Homer who makes these conversions available requires that you have a good tail wheel to start with. I may end up taking your suggestion and just going with a 500 x 5 wheel but they are set up for 1 1/2 or 1 1/4 axles so will require some modification. Rod +++ #8491 From: BruceAFrank@a... Subject: Re: Brake Disks > Another cost-saving tip is to go for seconds What is your source of these "seconds"? Bruce A. Frank +++ #8492 From: BruceAFrank@a... Subject: Re: 10" Tailwheel > If I was building a serious rocky-surface tailwheel, I think > I'd modify Bob's drawings for a 500 x 5, or maybe even a > 600 x 6. I have an 8" diameter Maule "Tundra." (No snide comments about Maule tailwheels, please) I thought this would be adequate for back country landings, tussock grass and sage brush. You don't think that diameter is up to the job? Bruce A. Frank +++ #8493 From: Russ and Penny Erb Subject: Another one to file away... Here are a four more tips that you'll want to file away for future reference. I was reminded of these while visiting Pat Fagan and using his lathe to turn down my tail tie rods. ... 3. Pat tells me that the 1-1/2" tubing for the axle for the 6.00x6 wheel won't quite fit into the wheel bearings. It will need to be turned down just a fuzz on a lathe. You'll need to this before you weld any of the other parts on. Make sure you have the wheels in hand before making the axle. What a pain to build the landing gear and then find the wheels won't fit! 4. You may want to make the axles a little longer than shown on the plan. Pat built his to plan and has just enough threads to get the cotter pin in. It would have been nice to have a few more. Russ Erb +++ #8494 From: Budd Davisson Subject: Re: 10" Tailwheel I suppose the best comment on stock tailwheels came from the Sherpa pilots when we were getting ready for alittle expedition accompanied by a Maule and a Husky, both with big tailwheels. The Sherpa guys wouldn't let them come along unless they both carried extra tailwheel assemblies. This proved to be important because the Husky broke it's tailwheel casting on our third landing site. if all you're talking about is rough grass and sage brush, it's no big deal. If you're talking about true bush where the rocks are plentiful an unpredictable, I'd think about something tougher. It's not just the tailwheel, but the castings tht are the problem. bd +++ #8495 From: "rodsmith52" Subject: Re: 10" Tailwheel I dont have any experience landing on cobbles or larger rock where a large diameter tail wheel would be mandatory. With my Maule M5 on 850 x 6 tires and a standard Scott 3200 with 8" tailwheel, I found that you would dig a trench in soft sand with the tailwheel. Not good when it takes nearly full power just to taxi. Once when I got above the tide line on a beach and stopped moving, I hopped out to discover that my lower longerons at the tail were actually flush with the surface. A Gar-Aero conversion to a much wider and maybe slightly taller tail wheel helped a lot. For the type of places I like to fly into I think extra width is more important than extra height for the tailwheel. Proto II has 75 pounds on the tail when empty. I calculated 299 pounds on the tail at gross weight and aft loaded as Bob presented in one of the newsletters. While you wouldn't want to go into a soft strip that heavy, it does help to have some weight toward the rear to keep the tail from lifting when you hit the soft spots. I landed on some pretty rough tundra a few times with the above combination. The fact that I never broke anything was probably more luck than skill. Rod Smith +++ #8497 From: BruceAFrank@a...> Subject: Re: 10" Tailwheel You have hit on a point that has crossed my mind, the cast parts. I have thought of taking the Maule tundra wheel and using that with a mount that I built from 4130. May decide to go that way after initial test period. Bruce A. Frank +++ #8511 From: "del" Subject: big tailwheels > You have hit on a point that has crossed my mind, the cast > parts. I have thought of taking the Maule tundra wheel and > using that with a mount that I built from 4130. May decide to > go that way after initial test period. I was thinking about this, and wondering if there is any reason why you couldn't just adapt a nosewheel assembly to the Bob Wheel? Then the only modification required would be possibly a different axle and whatever spacers are needed on each side for the hub/wheel to stay in position. You'd be able to use standard size tires without modifying the wheel at all. Having worked on a lot of tires, I get pretty leery when folks start talking about modifying anything designed to hold pressure. Del Rawlins -- #316, Anchorage, AK +++ #8525 From: Brian Cox Subject: RE: 10" Tailwheel I've scrounged pretty much all my parts on ebay so far. They very often have Scott or Maule tailwheel assembly, tailwheels only, etc. Just go to www.ebay.com. Get yourself set up to bid by clicking on their instructions. Then click on "eBay Motors", then "Aircraft", then "Parts". The first time you go through it there will probably be about 600-700 items. After that, you can just go in each morning and look at the "New Today" items. Once you identify something you want to bid on, click on "Watch this Item". Then you can just click on "My eBay" to follow the bidding progress day by day. Good luck. Brian Cox, #478 +++ #8526 From: Brian Cox Subject: RE: big tailwheels > I was thinking about this, and wondering if there is any > reason why you couldn't just adapt a nosewheel assembly to the > Bob Wheel? Aircraft spruce has Azusalite nylon wheels in 4" and 5", and Azusa & Matco aluminum wheels in 5". These are for homebuilt main wheels. the Matcon 5 inch wheels are specified for the Lancair and Vari-Eze mains. Azusas are less than $30, and the Matcos are about $75.50 for the 5" wheel with bearings. Brian Cox, #478 >>> 4sep02 #9154-11297 +++ #9424 From: "Montee, Dan L." Subject: Wheel Size Does anyone remember what size tail wheel is on either Proto #1 or Proto #2? I have the drawing but I don't remember what size Bob is using. +++ #9425 From: "alpine_traveler" "Doug" Subject: Re: Wheel Size In the drawing there is a supplier listed for the wheel (something like B&B) who is listeed in the homebuilt section of TAP. Is a BD5 main gear wheel. Got mine for around $25 IIRC. Can't exactly recall the true size and beats spending $60 thur A&S or Wicks. Actual tires for the listed rim are in the catalogs too. +++ #9426 From: John Dougherty Subject: Re: Wheel Size Bob used a 10" on the proto #2 but I beleive it was an 8" on the proto #1. +++ #9445 From: "Montee, Dan L." Subject: Tail Wheel Education This aircraft newbe needs a little education, I'm attempting to find a wheel and tire to build my tailwheel around. I've exhausted about every resource I can find in an attempt to decipher the secret aircraft jargon on wheel size and tire size. Much of what I find has stuff like 6.00 x6, or 5.00 x 4 which to me is a tire size followed by a wheel diameter, which doesn't help me with wheel selection or tire selection since I can't find the actual tire diameter and recommended wheel width for the tire. Other "coded " tire/wheel sizes include things like 12.50 S.C., or 10 x 3.5 -4. Is there a secret decoder ring for aircraft wheel and tire sizes? What is special about a tail wheel and a tail wheel tire? What's the risk in putting a "non aircraft" wheel and tire out behind? On the tail wheel drawing Bob lists B & B KS. I'm not sure what that means either and Google can't help me. I think we need a 4" diameter wheel, with 5/8" bearings, and I'm not sure about the wheel width. Actual tire size needed remains an enigma to me. Any help would be very much appreciated, Thanks. +++ #9449 From: Peter O Ludke Subject: Tail Wheel Education > This aircraft newbe needs a little education, Much of what I > find has stuff like 6.00 x6, or 5.00 x 4 These are common main and nosewheel designations. The 6.00 is the nominal section width (i.e. The width of the tire at it's widest point). The 6 is wheel diameter. Tire diameter (which varies a little by manufacturer (as does true section width)) and wheel width is not described by these designations. For what it's worth 6.00x6 main gear tires (the most common) run about 16" to 18" in diameter (unweighted), and 5.00x5 nose wheel tires run about 14" in diameter. Other common main gear tires on light singles are 7.00x6, 8.00x6 and 8.50x6. Off hand I don't know the width of the common 5" and 6" aircraft wheels, but I'd guesstimate them at about an inch less than the diameter. > Other "coded " tire/wheel sizes include things like 12.50 S.C., or 10 > x 3.5 -4. These are tailwheels. The tailwheels commonly found on light singles almost exclusively use either 8" or 10" diameter tires. The 8" tire designation is 2.80x2.50x4, and the 10" is the 10x3.50x4 mentioned above or alternatively 4.10x3.50x4 (same tire different designation). Both of these tires fit the same 4" diameter wheel. Again I don't know the width of the wheel offhand, but it's about 2.75" for the Scott and Maule tailwheels common on certified aircraft. If building a Bobwheel (tm) I think the 4" Azusa wheels (either in aluminum or nylon) should work well also. The hardcore bushpilot types often run bigger (and much more expensive) tires on their main wheels (26" to 31" ~balloon~ tires) and sometimes on the tailwheel (there exists an STC to mount a 5.00x5 nosewheel tire on the Cessna 180/185 tailwheel). Note that these tires have a non-trivial negative effect on both aircraft weight and cruise speed, and aren't really necessary unless you make a habit of landing on really rough 400' gravel bars and such. >>> 20may03 #11298-18250 +++ #12704 From: "rodsmith52" Subject: Tail Wheel Buffoonery I'm building the "Bob Wheel". I machined several of the parts quite awhile ago but didn't have the 2 3/8 stock to machine the body until this week. As usual it took me about 3 attempts before I had a keeper. I had it machined exactly like it looks on the diagram. When I started assembling the parts for a test fit it looked like the fork king pin was about an 1/8" too short. After much head scratching, some cursing and looking closer at the plans, especially the diagram of the completed tailwheel, my error became apparent. The diagram of the body on the plans is what it should look like with the cam brazed to it. I thought the cam sat on top of the body, in actuallity it slips over the outside of the body and is brazed flush with the top. At least I didn't have to redo the body. Just chucked it up again and turned the extra lip back down to the 1.500 dimension. Will have to brush up on my brazing skills before tackling that. Rod Smith #246 +++ #12732 From: Budd Davisson Subject: Re: [Bearhawk] AviPro Wing Test & newsletter > Bearhawk component we'd most like to see for sale that's not on the > list--the Bob-Wheel.I heard a rumor that AviPro was thinking of > tooling up to build them. yes, we are going to make them. No, I don't know when. Yes, soon. No, I don't have a price. bd +++ #12735 From: "Dave Roberts" Subject: Re: AviPro Wing Test - Bobwheel On the second page of the Bob wheel drawings, is the king pin drilled out almost all the way to the top. I can see the purpose of machining it out at the bottom for the fork cross tube. Is the rest just for weight reduction or am I just not seeing somthing that I am supposed to be seeing. I think I will do like you and make a spare also. Thanks Dave Roberts +++ #12737 From: "rodsmith52" Subject: Re: Bobwheel I also assume the king pin is drilled out most of the way for weight savings. I guess you could leave most of it undrilled if you wanted to. Rod Smith +++ #12743 From: Ken Beanlands Subject: RE: AviPro Wing Test & newsletter I must say that I've been very impressed witht he Matco tailwheel. I have the 8" pneumatic (courtesy of one of the BH list members) on the Christavia and it seems to be quite robust and has a very simple designusing the control springs between the rudder and tailwheel to provide the spring action for the castor/locking mechanism. Very neat design. All that remains is to actually put it to use. Ken Beanlands B.Eng (Aerospace) +++ #12774 From: "Steve Eldredge" Subject: RE: AviPro Wing Test & newsletter I've been using the Matco 6" solid for about a thousand landings and have had zero problems. A cheap and seemingly solid tailwheel for under $200. PS on a Pietenpol. Steve E. +++ #12791 From: "ken wardstrom" Subject: 14* versus 12* We have just finished installing the tail wheel and checked to make sure the craft sits at the 14* as indicated on the drawings and it doesnt it sits at 12* (1) have any of you guys that have completed to that stage checked this out, mabey we just screwed up. (2) will there be any difference in the low speed landing characteristics with this 2* difference. any comments appreciated _ ken +++ #12793 From: Budd Davisson Subject: Re: 14* versus 12* RE: Deck angles Very few airplanes that I've measured of any kind are at their described deck angles. Most are flat by at least two degrees. All of this can be caused by every thing from too much angle in the tailwheel spring to forgetting that the airplane may have been measured originally with bigger tires. Do you have 800 x 6's? To my knowledge, Bob has never had anything smaller on it and sometimes may have had 8.50's. The two degrees won't be noticed on either takeoff or landing. If you got down towards ten degrees, it might be. Worse case scenario is on really slow landings you may roll the tailwheel on first but I doubt it. bd +++ #12805 From: "ken wardstrom" Subject: 14* versus12* Thanks for the feedback, we shall continue as if everything is normal, but it sounds like if we want to get serious about fly fishing for steelhead in alaska a few modifications are required. (1) - extend the front gear to get the required 20* deck angle. (2)- add 2* nitro to the 100ll. (3)- install a 200hp. nitrous oxide system. I beleive with these modifications and bob showing us which midstream boulder to land on a person could get into some fine fishing that even the supercub guys couldn't get to. -ken +++ #15740 From: Pat Fagan Subject: recommendations ... Third, the one real problem I have had is with my tail spring. I still don't have mine right. The tail spring attach components in the plans are sized for a 1.5 inch wide spring. Be advised, the only place I could find that size spring is at a junkyard. If you want to have some springs made up for you, you will probably have to use 1.75 inch as that is what every place I checked with handles. That will require you to size up the bracket welded to the bottom of the tail post, as well as the U-bracket. Budd, what are you supplying with the kits? I had to guess at the arc and length of the spring to have a set made. What I thought was good turned out not to have enough arc once the plane was fully assembled. I rearced the springs so that the tail wheel pivot bolt (caster?) is vertical, but now the tail sits higher than the recommended (14 inches if memory serves) distance off the ground. I've flown with the rearced springs and it corrected the shimmy problem I had landing on pavement, but at gross weight, the spring is again compressed enough that the pivot pin angle is wrong and the shimmy comes back. After making 8, good, landings at gross weight, my springs took a new set that didn't return to normal even with all weight removed. I think I will try cutting off an inch or two before adding more arc, as I don't want the caster angle to be off when lightly loaded. Mike, perhaps you could include in a future Beartracks a scaled profile of the spring that Bob is using on the protos. It would save a lot of trial and error. Pat Fagan #232 Pearblossom, CA +++ #15746 From: Del Rawlins Subject: Re: recommendations > The tail spring attach components in the plans are sized for a 1.5 > inch wide spring. Be advised, the only place I could find that size > spring is at a junkyard. Pat, I don't know if this will help you or not, but the Bob Wheel drawings include plans for a 1.5" tail spring, which you could presumably have fabricated by a spring shop. For those of you thinking about bush operations, I had a good long talk with Boog last summer about tailwheels, and his recommendation is to forget about oversized tailwheel tires, unless you will be primarily be landing on the beach, where the extra flotation in sand can help. His opinion was that the larger wheels were just more likely to snag on stumps, rocks, and things often found on the usual unimproved fields seen in bush flying. -- Del Rawlins +++ #15748 From: Pat Fagan Subject: Re: recommendations > Pat, I don't know if this will help you or not, but the Bob Wheel > drawings include plans for a 1.5" tail spring, which you could > presumably have fabricated by a spring shop. Del, I've already made the commitment to a Scott tailwheel, which can use either a 1.5 or 1.75 inch tail spring. I had my springs made at a spring shop, but they were unable to provide 1.5 inch material. I was merely warning other builders to find out what size spring would be available before making/welding the bracket to the tail post. If you build to plans, than can't get 1.5 in. springs, you'll have to cut the bracket off and build another, larger one. Pat Fagan +++ #16958 From: pfflyerz@c... Subject: Re: Tailwheel was (A?)VSI on a Bearhawk > What was the fix for your tailwheel problem Pat? What kind do you > have? I have a standard Scott tailwheel. I had some springs made for me at a spring shop in the city. They consisted of 3 leaves, just like Bob's. The bottom 2 leaves were attached at the tail wheel, but the third leaf was short and only attached at the fuselage. According to Bob, automotive springs are not as hard as they need to be for our application. They should be 40 to 46 Rockwell. I don't know what mine are, but they were sagging at gross weight and taking a new set with each landing. I discovered what was happening was the two long springs were bending around the end of the short spring, so it was acting like a two spring system. I tried shortening the moment on all the springs, and clamping all three leaves together, but nothing worked. I finally made a new "short" spring and now have all three attached at the tail wheel and the fuselage. I was concerned with stress on the bolts with all three tied together, but I still get good spring action. +++ #17436 From: "Dave Roberts" Subject: Re: Tail wheel height > Can Pat or someone else who is flying get a measurement from the > bottom longeron at the tailpost to the ground for me. On the plans > it looks like 12". I am installing a tubular tail spring and my > oversized "Bob" wheel and need to get the angles right. I don't know if this will help you or not. My Avipro fuselage with the Bob wheel and 10" tire and spring built to Bob's specs with a weight of 130lbs on the tail wheel is 17 1/4" from the floor to the pad for the tailwheel spring. Dave +++ #17444 From: "Dave Roberts" Subject: Re: Tail wheel height > What kind of a deck angle on the fuselage does that give you? Budd, I'm not sure exactly where to measure the deck angle, so I measured on the top longeron between the wing attach fittings. The angle there is 15 degrees. That is with 8:50x6 tires and not with the gear loaded. If you want me to measure somewhere else or differently let me know. Dave +++ #17445 From: Bob Romanko Subject: RE: Re: Tail wheel height I could be wrong, but isn't deck angle on the Bearhawk the angle between the lower longeron (at the cabin) to the ground? Hmm....deck angle....cobwebs...cobwebs....phwwwwt! Planter Bob +++ #17446 From: Budd Davisson Subject: Re: Re: Tail wheel height Since nothing Bob does is ever square, that's probably not dead accurate. A more accurate place would be to run a rod or something through the wing fitting bolt holes and measure that. Then subtract 2 degrees for the incidence. A 15 degree deck angle is pretty steep for a modern airplane and I wonder how correct it is. bd +++ #17469 From: rsmith@f... Subject: Re: Re: Tail wheel height The lower longerons between stations B and D (front and rear door posts, front door) are parallel to the thrust line and what you use to level the plane. Slap your smart level on them and that should give you the deck angle. Rod Smith #246 +++ #17470 From: "Dave Roberts" Subject: Re: Tail wheel height > Since nothing Bob does is ever square, that's probably not dead > accurate. A more accurate place would be to run a rod or something > through the wing fitting bolt holes and measure that. Then subtract > 2 degrees for the incidence. Okay, I put the rod in the wing fitting bolt holes. Still 15 degrees. But minus 2 degrees and lower the front of the fuselage to add for finished weight it would probably be close to 12. That would probably be alright considering the bigger tires. Right? Dave +++ #17476 From: rsmith@f... Subject: Deck angle - was tailwheel height I just noticed that on sheet 1 of the plans, 3-view, Bob shows the deck angle as 14 deg. Rod Smith +++ #17477 From: "ken wardstrom" Subject: deck angle On #357 is 12* and we also mearsured from the floor to the rear spring support plate @ 16". We suspect we may have drawings for the short legs as there is no way we want to get the tail wheel any closer to the rudder. We suspect the 2* difference may increase the required landing speed, we're not going to do anything about it at this time, but it sure would be nice to get a solid answer for the future. thanks - ken +++ #17488 From: Budd Davisson Subject: Re: deck angle Re: deck angles Most tailwheel airplanes sit at 12-14 degrees and it's hard to tell the difference between the two on landing or takeoff. A number sit at 10 degrees (my Pitts) and a few go as low as 6 degrees, many Skybolts. When you get that flat there is indeed a difference in landing speed. I don't know what the 4412 critical CL AOA is but I'll bet its around 15-16 degrees. Maybe more with flaps. If you're within 2-4 degrees of Max AOA on landing that's close enough and you probably won't be able to measure the difference in actual touch down speed. Also rolling the tailwheel on first is perfectly acceptable in my book. Dropping it in tailwheel first, isn not. If you were to actually sit on the ground at max AOA, you're so close to stall during rotation and the last part of the approach that gusts can drop you REALLY hard. Also, don't forget the angle of incidence. It's the angle the wing sits at in relation to the ground that actually counts. As for short legs, I wasn't aware there were two gear leg lengths. Does anyone have information on that? If not I'll ask Bob. bd +++ #17522 From: "Dave Roberts" Subject: Re: Tail wheel height-deck angle > 12 degrees is a super common deck angle. What do you get when you > measure the lower longeron between the door posts as someone > suggested. 12.5 degrees Dave +++ #17577 From: Pat Fagan Subject: Re: Re: Tail wheel height-deck angle I checked out #232 today. Tail height at the front attach point of the tail spring is 14.5 inches. Deck angle is 12 degrees. Looks like a recent hard landing has "rearced" my tailspring again. I'm not at all happy with that spring, but don't know where to go to get a better one. For those planning on using a Scott tailwheel, DO NOT use the Maule style compression springs for steering. I did and was getting lousy steering and bending of the spring attach ear, even broke one off. I called Scott to ask about the problem and they helpfully advised that I use the proper spring. I bought the standard Scott tension spring and it taxi/turns so much easier and no ear bending. Pat Fagan +++ #17579 From: Benton Holzwarth Subject: Re: Tail wheel height-deck angle In the Nov '02 EAA Experimenter (pg 39) there was a bit on resolving tailwheel shimmy. It talked about how to arrange the pivot axis to stabilize the wheel, but, pertinate to your statement, it said, "...The Scott 2000 tailwheel does require some tension on the steering springs to control the unlock tension and hence shimmy. The Scott 3200 installation instructions say that chain tension is not required or recommended." Is that consistent with your experience? Benton +++ #17583 From: Pat Fagan Subject: Re: Re: Tail wheel height-deck angle > "...The Scott 2000 tailwheel does require some tension on the > steering springs I believe I have the 2000 tailwheel. I think the 3200 is the heavy duty ($500 more) model, but other than price, I don't know what the difference is. As long as the pivot pin axis of the tailwheel is perpendicular, I haven't had a shimmy problem, regardless of how much or little tension I had on the steering springs. The shimmy came from the leaf springs sagging from gross weight, and most recently, a carrier landing. Originally, I had a slight sag on the compression style steering springs. A mechanic at the field said they needed to be in tension. I tensioned them, then got a tail wheel shimmy at gross weight and that is when the ear snapped off. I went back to no tension on the springs but was getting no spring help for ground steering, it was all rudder. Even then, I kept bending up the ears. I put the proper tension springs on and tensioned them to the called for 25 - 30 lbs preload and it seems to be working great. Pat Fagan +++ #17585 From: Budd Davisson Subject: Re: Re: Tail wheel height-deck angle > Looks like a recent hard landing has "rearced" my tailspring again. > I'm not at all happy with that spring, but don't know where to go to > get a better one. We should have our springs available soon. It's to Bob's profile and hardened. bd +++ #17588 From: "Dave Roberts" Subject: Re: Tail wheel height-deck angle > Looks like a recent hard landing has "rearced" my tailspring again. > I'm not at all happy with that spring, but don't know where to go to > get a better one. There is a machinist here in Montana that builds tailwheel springs to your spec's. If Budd's spring doesn't work for you I could give you his name and #. Dave +++ #17593 From: Scott Bailey Subject: Re: Re: Tail wheel height-deck angle Additionally, your local 4x4 shop should be able to direct you to a good spring shop. They will make just about anything you can spec out. My last experience with a spring shop (Valley Spring in Phoenix, 7 years ago?) was very good. They built some very nice custom springs for a 4x4 project of mine at a VERY reasonable price. Although there certainly is advantage buying AviPro, it may make more sense to buy local. Scott Bailey +++ #17594 From: Del Rawlins Subject: Re: Re: Tail wheel height-deck angle > Additionally, your local 4x4 shop should be able to direct you to a > good spring shop. I believe that Pat did have his spring made by a local spring shop, although it sounds like they did a lousy job with the heat treat. -- Del Rawlins +++ #17609 From: pfflyerz@c... Subject: Re: Re: Tail wheel height-deck angle > There is a machinist here in Montana that builds tailwheel springs > to your spec's. If Budd's spring doesn't work for you I could give > you his name and #. Dave, I'll keep that in mind. My springs were made to the profile I need by a spring specialty shop, but they had no idea what hardness the steel was, nor where I could go to have it checked/amended. I suspect your machinist might have the same problem. Pat Fagan +++ #17613 From: "Bruce A. Frank" Subject: RE: Re: Spring sprang sproingg On the V-6 STOL most builders have used the tail wheel spring from an Aronca. I think it is the Champ...not sure anymore...I vaguely remember the designation of the model of plane containing ...7c.. in its designation in both Univair and Wag Aero. It is a three leaf unit that has worked well. It used to be sold by Wag Aero for use with 2+2 Sportsman. I bought mine from Univair. I don't have the latest Wag Aero catalog and the their web site shows only a tail spring for the Cessna. Univair will likely still supply it (probably they have the STC/PMA for it.) Bruce A. Frank +++ #17616 From: Sam Butler Subject: Springs Here in Portland OR, we have two metal treating outfits. Look in the yellow pages, and give them a call, and ask to talk to their metallurgist, I've found that both of the ones I've talked to have been very helpful, and very knowledgeable in all areas, we have had very small projects done and if you're not in a huge hurry, they'll throw your project in with another batch, and that keeps the cost reasonable. Sam Butler +++ #17620 From: Budd Davisson Subject: Re: Springs As I mentioned: we've gone through the brain damage of finding good spring and heat treating people and already have prototype springs and we're just trying to decide which vendor to go with. The springs will be about $100 but at least will be guaranteed to fit and work. bd +++ #17622 From: "Dave Roberts" Subject: Re: Tail wheel height-deck angle The machine shop made mine and then hardened them to rockwell 40 as per The Bob's plans. My spring cost about the same as Budd's so if Budd's works for you that would probably be the way to go. But if you need a different shape this guy seems to do a good job. Although he said if I fly to Alaska I have to take him along. Dave +++ $Id: 2.3.4-Fuse-TailWheel,v 1.11 2003/05/22 03:24:00 bentonh Exp $