Welding engine mount

[rawheels]

I had someone weld a plate onto the engine mount of my other plane (Kitfox). Got a second hand message from the guy saying "might want to anneal the mount before you use it". I did a quick google search on annealing, and it doesn't exactly look like something you do at home. Is that a common practice after welding, and if so, how do I go about doing it?

[mtaylor]

Did he possibly mean "stress relieve" instead of "anneal"? Stress relieving is simply a matter of heating with a torch the HAZ (heat affected zone) to a dull red then allow to cool very slowly by working the torch flame over the area as you slowly withdraw the torch. Was the plate welded on with a torch or TIG? If TIG, I'd stress relieve. Might also be a good idea to have the mount in a jig or on the frame to prevent warping.

If he indeed means to anneal, that's outta my realm of knowledge and ability.

Good luck.

[mtaylor]

Oh, and also, keep doors and windows closed. You don't want ANY kind of breeze on the piece you're stress relieving as it is cooling down...

[rawheels]

Thanks. You are correct, he meant stress relief, not annealing. Not sure why he didn't do that when he welded it. He said that he would do it the next time he was around, but is currently out on an IRL racing team. Can I do the stress relief with a propane torch, or do I need to wait around until someone with some acetylene torch is around?

Ryan

[JBMoore]

Follow Mark's advice about stress relieving and you should be fine. I did all mine with a oxy-acetylene torch.... I don't know if a propane set up will get you to the dull red color needed.

Jeff Moore