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Steve K
01-12-2016, 09:36 PM
Hit a snag, unexpected. Have several parts to fabricate for a Buccaneer 2 project. several tight bends required in 6061-t6 1" dia, 0.049" and 0.065" thick walled tubes. As this sort of thing quite common on many ultralight designs, I figured living in Portland metro area home of Van's aircraft and several other kit aircraft businesses, I should have no problem finding a shop to bend thin wall aluminum tube. found one shop in St. Helens OR that advertised mandrel tube bending and they just told me "no can do". My first choice, have Aero Adventure (FL) do the job, they said they can. I sent a part sample as pattern before Christmas and now I can not get them to answer emails or phone calls. Still need the parts, project completely stalled till I do.

Can anyone in this forum point me to a company local or even not local that can do the job? Or identify a tool or method that I can use to bend these myself?

Any help would be greatly appreciated.

Steve

Dana
01-13-2016, 05:19 AM
How tight is "tight"?

One technique, that I've never tried, is to fill the tube with sand or Wood's metal before bending. Or perhaps a conduit bender might do it?

If you're calling local shops, don't say it's for an aircraft.

martymayes
01-13-2016, 07:54 AM
A can't imagine those bends can be accomplished without a mandrel bender. There are some benders geared for home use that (with practice $$$) will do the job. Not sure of the price. Google bending soft alum. tubing or search YouTube for the same.

cliffo
01-13-2016, 10:25 AM
Give a call to the Pipefitters or plumbers local union hall and I'm sure the folks there can point you in the right direction.

Mike Switzer
01-13-2016, 11:49 AM
3/4" EMT (thin wall electrical conduit) is just slightly smaller than 1" diameter, you might see if you can borrow a 3/4" conduit bender from an electrician & see if it works. I just measured a conduit in my shop & it looks like you can get roughly a 6 5/8" radius bend. (measured from a box to the center of the conduit)

gmatejcek
01-14-2016, 07:53 PM
Hi there-

Find yourself a local hydraulic supply house. If they can't do the work, they should know who will.


Hit a snag, unexpected. Have several parts to fabricate for a Buccaneer 2 project. several tight bends required in 6061-t6 1" dia, 0.049" and 0.065" thick walled tubes. As this sort of thing quite common on many ultralight designs, I figured living in Portland metro area home of Van's aircraft and several other kit aircraft businesses, I should have no problem finding a shop to bend thin wall aluminum tube. found one shop in St. Helens OR that advertised mandrel tube bending and they just told me "no can do". My first choice, have Aero Adventure (FL) do the job, they said they can. I sent a part sample as pattern before Christmas and now I can not get them to answer emails or phone calls. Still need the parts, project completely stalled till I do.

Can anyone in this forum point me to a company local or even not local that can do the job? Or identify a tool or method that I can use to bend these myself?

Any help would be greatly appreciated.

Steve

mtgunner
01-14-2016, 08:44 PM
Steve,
I live in Oshkosh WI and worked at Basler Turbo Conversions for 16 years. We had to bend 1" diameter alum tube for our hydraulics system all the time. It was 5052-0 x .049" wall alum tube but I am pretty sure our bender would handle 6061-T6. How big of pieces are the ones that you need bent, what is the bend radius, and what is the angle that it needs to be bent to? I am retired from there but get me this info and I will talk to my friend that works on the hydraulics system and see if he would be able to do that like after work some day. PM me and we can exchange e-mails or phone numbers.
Mark

gyrojohn
01-14-2016, 09:33 PM
6061-T6 is hard to bend. If I remember right Powrachute in Hastings MI gets mill runs of a special variant of 6061-T6 to use on their powered parachutes. They may be able to help.

SprintUS1
01-14-2016, 09:40 PM
[QUOTE=Steve K;52663]Hit a snag, unexpected. Have several parts to fabricate for a Buccaneer 2 project. several tight bends required in 6061-t6 1" dia, 0.049" and 0.065" thick walled tubes. As this sort of thing quite common on many ultralight designs, I figured living in Portland metro area home of Van's aircraft and several other kit aircraft businesses, I should have no problem finding a shop to bend thin wall aluminum tube. found one shop in St. Helens OR that advertised mandrel tube bending and they just told me "no can do". My first choice, have Aero Adventure (FL) do the job, they said they can. I sent a part sample as pattern before Christmas and now I can not get them to answer emails or phone calls. Still need the parts, project completely stalled till I do.

Can anyone in this forum point me to a company local or even not local that can do the job? Or identify a tool or method that I can use to bend these myself?

Any help would be greatly appreciated.

Steve[/QUOTEasy]

My sprint called for bending 3/4" .049 square tubing for the canopy Needed two bows and the instrument panel. The bows are 44.5" wide and matched the curve of the Plexiglas. I bent them, and they came out very nice on a wood mandrel I made. I cut 3/4" plywood into three half circles. Center 3/4" width (you would need 1inch. glue up 1/4" to the 3/4) and 7" in diameter. Fasten two 9" diameter to the sides looks like a pulley. I made half circles and worked fine. I set it in a large vise. Make small bends every 1/2" or so. Keep matching it against a form that you want it to match. They came out great. Tubing should by a piece of cake. for tight bends I bent some steel round one end similar to a conduit bender pivot. Go for it. Could not be cheaper to make.
Good building,
Joe G.

flyrgreen
01-15-2016, 09:55 PM
Several good leads here already, so you should be fine. But allow me to echo the poster who cautioned against mentioning "airplane". This is large advice, especially for something that is structural. They'll turn you down flat every time. I've learned to use the term "homebuilt recreational vehicle". It IS the truth and I've never been inexplicably turned down since I adopted that term.

crusty old aviator
01-21-2016, 11:14 AM
Flyrgreen and Dana make good points about not mentioning "airplane." But I wouldn't mention anything about a vehicle, either. Say it's for a garden hose reel stand, or and plant stand on your patio, or a garden tool rack...something that has to look good, but wouldn't scare their insurance goomers. There are many ways to bend the tube you mentioned, but like mtgunner inferred, we can't really give you applicable advice without knowing the radius and angle of the bends you need to make. 6061-O bends a lot easier than -T6, so I'm not sure if a rig set up for 5052-O will handle it...at least you're not trying to bend 2024, that stuff is stiff!

Steve K
01-29-2016, 03:51 AM
Thanks, and thanks to all above. All the bend radius are the same at 3.5" to tube center. Bends are as small as 5 deg. up to 35 deg.

I figured I would likely require annealing the tube in bend region.

Dana
01-29-2016, 05:25 AM
3.5" radius is a pretty tight bend for a 1" tube.

crusty old aviator
01-29-2016, 01:27 PM
You should be able to do that at home with a home made, hardwood mandrel. Fill the tube with sand, and contain it by plugging the ends, before making the bends, to minimize crimping and ovaling the cross section of the tube at the bend.

gyrojohn
01-30-2016, 10:23 AM
You should be able to do that at home with a home made, hardwood mandrel. Fill the tube with sand, and contain it by plugging the ends, before making the bends, to minimize crimping and ovaling the cross section of the tube at the bend.

Filling with sand is an old technique but it turns out to be harder to seal the ends as one would think. The force of the bending pushes out the sand. A mandal would help. A good Pines bender with a double kunckle mandrel can do 1 to 1 bending with 0000 AL in a dead soft condition.
But I repeat the the alloy and temper of the material is what determines what one can do.
Powrachute is the biggest manufacturer of powered parachutes in the world and they make their frames out of 6061 T6 so they have lots of experience in bending this material. I dodn't know if they have the exact size you need but I would contact them rather than a non aeronautical company who normally uses other material.