Many of us weld and buy used cylinders at auction, via Craigslist etc because it's MUCH less expensive than renting.

Pete S. on Weldingweb posted this and now I won't have to wait on my LWS to lose my cylinders.

https://portal.phmsa.dot.gov/rinlocator

Original thread:

What tanks can I refill with helium mix?

You want the blue locations for hydro testing but the "visual" locations will nearly all be local welding suppliers who of course sell gas so it's handy for that.

Shop life is wonderful with industrial gases. I have nitrogen (purging and pressure testing AC systems, vacuum is poor for finding leaks), CO2 (MIG welding, bead seating with my 200 psi regulator, brief pneumatic tool operation in the field, etc) and the usual MIG mix, argon, acetylene, oxygen and LP. I learned what brands my local supplier accepts for exchange (the welding industry consolidated down the decades) so I know what to search for. It's easy to do.

 

The last time I got acetilene they just exchange cylinders. Said they don't recognize "owned" or rented cylinders.

 

There is no universal policy. If your LWS are totally cool then those are the people to support with your business!

Small sizes are typically swapped out anywhere so long as they don't bear the neck ring of the competition.

Some LWS can refill cylinders which have current hydro at their site instead of sending them off. I'd love to have one of those near me but as the owners retire and sell off their business to Airgas or whoever then corporate take over.

 

here in joisey most of the places will only take in and exchange their own tanks. and they test for free.
if you bring in a tank that is not one of theirs they will not touch it.