re-arching an aluminum tailwheel spring

[tx_swordguy]

Is it possible to re-arch an aluminum tailwheel spring? I know steel is done all the time but not sure of the aluminum. wasn't wanting to put a drastic bend but just bring it up a bit. I have a 12 ton press and a 20 ton pipe bender. While the pipe bender would be ideal angle wise I am not sure if the unsupported center of the die (where the pipe actually sits) would support the spring enough. I tend to think the press is the better choice.
Thanks Mark

[HighWing]

I think a lot depends on the specific alloy and heat treatment. Years ago, I was making some specialty parts using 7075- T6. At full heat treatment, bending was nearly impossible without hearing that ping before picking up the two pieces. I suspect, if you could neutralize the heat treatment, then bend followed by re-heat treating, it could be done. For my project, I would buy the non HT aluminum, bend then heat treat to T6.

[jiott]

I have heard of guys over-bending the Grove landing gear in a hard landing. They sent it off to Grove and it was rebent to original shape. Very likely Grove anneals it, rebends it, then re-heat treats it. I would think the same could be done with the Grove aluminum tailwheel spring.

[Av8r3400]

Very likely Grove anneals it, rebends it, then re-heat treats it.

This is exactly what they do. I had a bent gear that I was going to use on the Mangy and this is what they quoted me to repair it. I decided to get a new, custom spring made from them instead.

[WWhunter]

Sort of along the same line.. I bought a plane that has the round tapered type landing gear legs. The gear was bent and restraightend when I got it. Apparently bending it past a certain point destroyed the heat treatment as it bent again soon after I purchased it. No hard landings, just a gradual sag is what I noticed. Ended up installing new legs. Maybe if the previous owner had reheat treated them they would have been fine.

[jrevens]

Sort of along the same line.. I bought a plane that has the round tapered type landing gear legs. The gear was bent and restraightend when I got it. Apparently bending it past a certain point destroyed the heat treatment as it bent again soon after I purchased it. No hard landings, just a gradual sag is what I noticed. Ended up installing new legs. Maybe if the previous owner had reheat treated them they would have been fine.

If I had to guess, they were probably heated (with a torch) in order to bend them back, and then not re-heat treated. Cold bending won't diminish the hardness from heat treating and tempering, but it may actually increase the hardness, due to work-hardening.