Del Rawlins wrote:
In Leon McAtee wrote:

Del Rawlins wrote in message
...


To add to Corky's comments, 4130 can be TIG welded with little worry
about the HAZ as well, which is how I am welding the steel components
of my Bearhawk together. I may do some stress relief of critical
clusters and attach points using a rosebud torch,

Seems to be a contradiction here. If TIG works so well why bother
with the "stress relief of critical clusters and attach points"? This
either implies that the welding process is not completely acceptable,
or the rest of the structure has been over built and less than ideal
welds are acceptable. If the later is the case why not use something
like 1026 DOM and forget the post heat alltogether?


No contradiction. I haven't been convinced that stress relief is
necessary, but neither have I been convinced that it hurts anything, and
it only takes all of a few minutes to accomplish. From what I can tell,
even experienced welders can't agree on whether or not it is desirable.


I'm not from Missouri but I still need to be shown that TIG is truly
acceptable for welding 4130.


Over and above 50 odd years of experience in the aerospace industry?
I'm going to say Arkansas, but that's only a guess.



It was my understanding that the problem with TIG is that it doesn't put
in ENOUGH heat. That is, it melts the steel at only a very limited
section, as soon as you move on all the surround steel sucks the heat
out, basically quenching the weld and making 4130 brittle.

Don't know if it was my lack of skill, the cheap TIG contraption I was
using, or misaligned stars, but the few test pieces I TIGed together
came apart with my bare hands. I'm strong, but not like that. I
decided to stick with OcyAcet.

Luckily, I'm almost done with it.

--
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"Ignorance is mankinds normal state,
alleviated by information and experience."
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