I'm looking to make my wife one of those Bells made from the large Gas cylinders. I'm not planning on cutting the decommissioned cylinder myself however I am looking for suggestions on what the safest cylinder I should look for. I've been told that CO2 is the safest for cutting into. Is this correct? What about Argon?

I'm in the eastside of Seattle, WA area and of the few places I have called either send off their decomissioned tanks or they only have Oxy-Fuel ones. Most have been generous in stating they'll hand off a C02 K size when one comes in, but 2 years have passed - and I'm branching out now for suggestions.

K's diameter just feels right - the height won't matter as the cut height I'd expect ~36" tall. An XL (14.5") would be really neat but at the same time huge.

Once I find the tank or tanks if I can find 2. My next question will be who will cut them and what documention will I need to prove they are proper?