On Thu, 17 Oct 2013 14:06:10 -0700 (PDT), stryped
wrote:

On Wednesday, October 16, 2013 8:12:42 AM UTC-5, stryped wrote:
I have been reading about stress relief and general metalworking. If a person wanted to prevent stress cracks in somethign like a t bucket frame, is it a good idea to peen weld areas? Can an air operated needle descaler work? Is hand peening possible?

I read my bobcat is capable of tig, but it lists it as "non critical". Why would that be?

One other question, I read that a root pass is not supposed to be peened? I dont quite understand that but does that mean you cant use a needle descaler to remove flux?

Also, is it good or bad to grind a weld flat after welding? Seems I read the heat from grinding can cause problems as well.

I believe that the general standards are not to grind welds as the
raised bead actually contributes additional strength to the joint. A
guy that built welded steel boats told me that in order to pass
certification the welds could not be ground flat.

As the parent metal is actually melted in the welding process it seems
illogical to believe that any additional heat generated by grinding
will effect the strength, excepting of course an "air hardening" alloy
which is common in bicycle frames and probably less common elsewhere.
--
Cheers,

John B.