RE: WACO YMF
I think that I would rather see the tailwheel strut made from something like music wire. Failing that, you can probably temper the wire that you are using by heating it until it is yellow hot (past red hot) and oil quenching it. You may need a forge to generate that much heat. Normally unless you have the means to super oxygenate the flame, (similar to a cutting torch) you will not be able to achieve that temperature. Try it with a scrap piece of wire and your Butane torch. You will need a container with sufficient engine oil to submerge the part . Also be sure to have a fire extinguisher on hand in case you ignite the oil. You probably will not do this, but better safe than sorry.
Bill, AMA 4720
WACO Brotherhood #1