On 12 Jul 2006 04:58:49 -0700, "mhorowit" wrote:

Somewhere I read about a welding exercise where the student built a
tube frame of some sort, pressurized it, checked for leaks, then
smashed it flat and rechecked for leaks.
I've looked thru my books but can't find it. Anyone recall where I can
find a description of the exercise? - Mike

I have no idea what any official test looks like except a vague
recollection that the australian test was an N shape coming up off a
tube. you had to weld it bolted vertically up off a bench to
demonstrate welding in all positions. it was then sliced up to check
for carbon and impurities in the weld. there was also a set of butt
welds in sheet.

I have a friend who is a crackerjack welder but lacked the confidence
to tackle a welded tube airframe. even after he welded a tailwheel
that I flew across australia and back.
I had him weld up a square in tubing using a different type of joint
in each corner. he then stressed this to destruction in a press.
it took two tons to destroy each corner and the joint failure was in
the tubes a little way off beside the weld. with that reasurance he
has almost completed an absolutely schmick low wing sonerai two.

try it it worked for him.
Stealth Pilot