RainLover wrote:

Okay... here's the setup:

I Bought a 6' diameter stainless steel tank from a local scrap yard.
I got it for an incredible price because there was a foot thick, VERY
dense foam lining it that I needed to use a chainsaw to cut before I
could break it out....

This tank had been drop tested and had dents on the top with '1st
drop, 2nd drop... etc and the height dropped from on it...

When I got out all the foam, written on the inside were the words
"Nuclear Packaging". The scrap yard had checked it with they geiger
counter and it read ZERO... so that's okay.

MY QUESTION:
What sort of Stainless Steel would you guess this to be? I'm creating
a couple of sculptures from the material and would like to use the
proper welding rod... I'll go with 309 barring a good guess of
something else.

Thanks!

James, Seattle (port orchard), Washington, USA, Earth
My bet is it is safe. It was likely a layer of containment to protect from
mechanical problems in a crash during transport. If the internal didn't leak
Then all is well.

Now : I don't know your supplier. Nor their equipment. Being a Physicist, I tend
to guess the scrap yard has a yardstick quality instrument that can't measure
some stuff, but is more go no-go for the most part.

What I would do to sleep at night is this :

Buy some fresh color film. The faster the better - e.g. 400 or 800 ASA.
some 2 1/4 x 21/4 roll film. Camera store for this.
If they have Tri-X in black and white and can develop for you - ok.

Buy two rolls - develop in two stores or at two occasions. Tell them you want
the film and the film might be blank or near blank. Prints wanted on each.
Put the film inside the tank - still wrapped up on the spool - but no foil around the
film. Then after a single role is developed :

Look for pin holes e.g. black dots on the film and white dots on the paper.
General fogging indicates a larger exposure and the density strength

Remember - we are play-acting scientist here - If the first is slick clean - develop
the second roll. If slick clean - you are slick clean and ready for fun and games.

If the film is foggy or spotty you should get professional help to determine threat.
My bet there isn't. The local health department might be able to give you a simple
test with their machine - far better than the one at the steel supplier...

Martin [ Suggesting some ideas I would do in this position, not telling what should be done ]

--
Martin Eastburn, Barbara Eastburn
@ home at Lion's Lair with our computer
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder