I have an old Walmart garbage can that is oval in shape and was marked as stainless steel when I bought it. It's been sitting in my garage for a while and it looks like it has pretty good dimensions for the shell of a gas forge.

I'm betting nervous about using it though. "In rust we trust" and all that. Is there a way for me to safely assess weather this is going to kill me with fumes if it gets hot?

For me that is way too big for a propane forge.

What is it that you want to do that needs a forge that size?  Would have to be ornamental twists for railings I would think as for something like a sword you only want to heat what you can work before it cools off and blade alloys have narrow forging temperature ranges. Building a gas forge larger than you need is like stuffing the excess length/width/height with dollar bills each time you fire it up.  Cheaper to build multiple forges each sized for the need.

If it's really stainless steel then fumes are not an issue.

Nothing ornamental. Just some basic beginning forging. Forgot to mention I'm planning on cutting it in half. Using the whole can would definitely be too large for anything I would want to do.

Half would work better.  How thick a liner?

I've been keeping the sheet SS from a very similar garbage can for when I can eventually make time to make a propane forge. Mine isn't plated with anything. If you aren't confident in identifying stainless steel, then you can verify if yours is by spark testing or by abrading a small area or cutting it and then seeing if the resulting fresh surface rusts readily or not. If you just take it apart and inspect the edges (including of your faster holes), I would expect to see rust there if it were plated stock; the manufacturing process for a relatively low value item is unlikely to include a plating step after the sheet has been rolled into the can form. 

When I decide what size the first forge will be, I'll cut the sheet to size and rivet it together into my forge shell. I could probably make 2-3 forge shells of different sizes from it. It seems a bit big to me to just cut it in half, but that is for what I want to do; YMMV. 

10 hours ago, Chris Williams said:

If you just take it apart and inspect the edges (including of your faster holes), I would expect to see rust there if it were plated stock;

You were right on the money. Rust around the screws and rivets.

11 hours ago, ThomasPowers said:

Half would work better.  How thick a liner?

Was thinking about using 2 layers of 1 inch ceramic wool with cabosil coating. They will both be here on Wednesday. I think I'm going to make a coffee can forge first just to work with the materials a bit. Don't want to waste time and material

So far, your ideas seem right on to me.

Yep, especially cutting the container down, should make a fine forge body.

I wonder if they are still selling them?

35 minutes ago, Mikey98118 said:

I wonder if they are still selling them?

Looks like the original might have been discontinued.

 

 

They do have an alternative though.

That general style is fairly common. I've had a few over the years. 

I have a couple of piece of stainless pipe from commercial kitchen exhausts in various sizes that are heavier gauge and I bought cheap when the Re-Store had a moving sale.

How does the price of the waste basket compare to an appropriate length and diameter of SS stove pipe?

Frosty The Lucky.

The trash can is *much* cheaper if you buy both new.  I think I paid US$4 for the piece of stainless that was of similar size but of course I was buying used and at moving sale prices...why I bought it! Stainless stores nicely.

9 minutes ago, ThomasPowers said:

The trash can is *much* cheaper if you buy both new.

That's why I asked. I won't recommend SS stove pipe again. Thank you. 

Frosty The Lucky.

Now I don't know about the stainless steel wood stove pipe; never priced any new.  I did get a piece to replace the bottom section of my woodstove chimney for our house's backup heater.  (Last joint where it's the hottest was rusting out.) Not nearly as heavy as the commercial stuff I snagged for the forge.  It's now a beautiful Peacock Purple for the entire section due to temper coloring.

I just searched out SS stove pipe online and it's spendy, IIRC 6" x 48"/$56. Cut in half and sapped together gives you 12" dia x 24". 

Pretty spendy though, guess I'll stick with plain steel shells.

Frosty The Lucky.

The commercial HVAC stuff for restaurant kitchens' fire suppression systems is much much thicker and cheaper the way I got it.  It gets welded together!

I like thick walled forges; my most commonly used one was made from a section of OXY tank!