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Old July 15th 06, 02:40 PM posted to rec.aviation.homebuilt
Stealth Pilot
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Posts: 78
Default What was that welding exercise/exam?

On 14 Jul 2006 13:00:20 -0700, "Dan Horton"
wrote:


stress to relax through deformation of the tube (it necks, swells, or
bends). This is not entirely successful, since the process again
involves shrinkage when the section cools, as well as introducing
variation in tube diameter and wall thickness. Although significant
stress may still remain in the end, the process can be useful in
straightening warped structure.

These days most professionals tig. The tube length warmed in the
process is less, so expansion is less, and residual stress after
cooling is less. Very few bother to stress relieve. Same for
mig-welded frames. You want to use gas? No problem, but skip the
reheat unless you need to correct warpage.


if you build a little standoff holding clamp to hold the tube straight
it will cool straight with no warp.

I'll email you a digital photo of a holding clamp. it screws up with
just the gentlest of holding force.

Stealth Pilot