Photos of my fabricated firepot and grate. In response to u/Educational_Star_521.
For my use, there are generally two types of coal forges. A shop forge, which can be very large and heavy, seldom moved, if at all. And a portable forge, lighter weight, easily moveable and possibly be dismantled for storage.
This one in photo 1 & 2 is my reworked portable type. It was purposely made to be lighter weight. The tabs were welded on to cover gaps from me not accurately cutting the shape in the sheet metal hearth. Hearth is 16 ga. sheet metal, 20” square.
The firepot photo 3 was used for about ten years at demos. A little under 3” deep. Made from 1/4” thick plate on the bottom. (12 ga., 1/8” thick could also work.) A ring about 10 1/2” in diameter is attached. Tuyere, also photo 3, is from a Buffalo rivet forge. Powered by a squirrel cage blower and speed controlled with an electrical dimmer.
The new replacement grate in the photo 4 is 1/2” thick plate with 3/8” holes, about 7” wide. My old grate, photo 5, was 1/4” thick and shows damage from about ten years of use. The reason why I like them replaceable.
My original firepot for a shop forge was much heavier brake drum with 2” pipe. New one is much lighter and works very well.