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Almost finished with my first propane forge. The shell is 11 gauge sheet metal I bent around a 12” diameter pipe to form the vault on top. The bottom is flat. I bought a Pine Ridge LP 290 burner which is fed by a 2” black pipe. I thought about making my own ribbon burner but liked their burners and decided to put my time into other parts of the build. I used 3” of rigidized 8lb Durablanket on top and bottom because the burner protrudes 3” inside the shell. I only used 2” on the sides to maintain the inside width I wanted. I added a ½” Kastolite liner and a nitride bonded silicon carbide kiln shelf floor. I cut the insulation carefully so that the burner fit snuggly. The Kastolite slightly overlaps the edge of the recessed burner so I shouldn’t have any leakage around the burner to the outside. I painted the inside with some Matrikote I bought from Wayne Coe. Inside dimensions are 19” deep, 8 ½” tall and wide. The doors are insulating firebrick. I made a brick from Kastolite but it was heavy for my use so I decided to stick with the light weight insulating bricks for now. The upper bricks in front are held in place by compression with a bracket on each side. The lower bricks slide open/closed using a pair of 24v linear actuators I found on Craigslist by accident. An example of finding something I didn’t know I was looking for but knew what to do with when I saw them. I bought a 24v power supply and a double throw center off momentary rocker switch from Amazon. The back is closed off with fire brick but can be opened for pass thru as needed. All metal is well outside the flame zone so I don’t think I’ll have any problems with warpage. Not sure if I’ll like the actuator controlled doors but it will be fun to see how they work and if they survive the heat. I’ll leave the front bricks apart a bit for the exhaust and can open to a max of 6” with the actuators. I can easily work at the back end if I need more than a 6” opening. I have a 100lb propane tank with a Harris 25GX regulator. From there, I run a ¼” braided stainless hose to a ball valve, then a Red Hat normally closed solenoid valve controlled by a Cleveland Controls pressure switch and then to a needle valve. You can hear the solenoid valve click open in the video once I turn on the blower. The propane enters the airstream thru a mixer made from a 2” T and some 1/8” tubing. Air from a Centaur PB50 blower is controlled by a 2” gate valve. The needle and gate valves are near the front of the forge so I can see the flames as I make adjustments. I removed the variable speed control from the Centaur’s motor because it seemed redundant with a gate valve and slowing some motors can overheat them. I have multiple uses for the blower and can use all the air it puts out. I wired in a 25’ 14 gauge extension cord. All 120 volt wiring is protected by FMC. The 24 volt wiring is not encased but is held out away from the forge body by zip tying them to the 2” black pipe which should never get very hot. I made adjustable tool rests and castable refractory porches for the front and back. I made a 10” wide air curtain using some thin sheet metal and a 1 ¼” T. The T allows me to clean out anything that falls in. The air curtain uses the burner blower’s excess capacity. I don’t have a valve on the pipe going to the air curtain and don’t think I’ll need one since the pipe reduces to 1 ¼” but I can add it later. The pvc pipe to the air curtain has a barb with attached clear tubing that goes to the pressure switch. I also drilled a hole in the metal pipe to direct a small amount of air to help keep the 24v power supply cool. A dust shield helps keep the power supply clean. The forge stand is yellow only because most of the scrap I bought at the local salvage yard was already painted, in good shape and I didn’t want to spend the time to grind it all off. I just cleaned up my welds and touched up the paint. I kinda like the yellow now. The propane hose is held up out of the way with an adjustable support. The stand has casters at one end and adjustable legs on the other. The adjustable legs allow me to make the forge stable and level on most surfaces and prevent the forge from rolling off on its own.