Non-Obvious Skills to Learn as a CPL

[Colonel]

Regardless of the paper, if you mig or tig a cluster, be sure to heat it up with an oxy torch afterwards to relive the stress and avoid cracking in the future.

Not sure how many people bother to do that any more, but ....

Same thing with an exhaust. Especially after repair, they don't fit very well on the studs and you have to force it on then tighten up the nuts. And people wonder why they crack so soon afterwards?

Here's the trick. Force the ill-fitting exhaust on, and start the nuts. Then, heat up all the vertical stacks with a torch so they have a section which is glowing and plastic. While they are hot, tighten up all the exhaust studs and the flanges can square to the ports. After it cools off, the exhaust will slide on and off the engine perfectly. No stress. No cracks. No leaks.

Doesn't cost hardly anything, just a little gas and some time. But no one gives a shit any more, and that's ok.

[Squaretail]

It’s funny, the welding snobs say you can’t mig an aircraft fuselage - only tig or oxy.

I've watched a lot of videos on the subject, and while all of them have this opinion, I haven't really seen a compelling reason why one couldn't. The only thing I can see is that its easier to do a better job on the relatively thinner material that makes up airplane structures, but that doesn't make it impossible.