I just recently finished building my first forge out of a used portable compressed air tank, single venturi propane. I got the tank free from my neighbor. 1" Inswool, 1/4" thick Satanite (2 coats), 2 thin coats ITC-100, 3/8" thick floor of Bubble Alumina. I bought the materials and venturi kit from High Temp Tool & Refractory, and I highly recommend them.
The venturi is angled properly thru a 10 0'clock mounted burner seat and gives a great swirling effect. The first blade I forged in it got hot too quickly at 5psi so I turned it down to 3psi. My knifemaking mentor and teacher here in Kansas City said it definitely seems like it will reach welding temp and we will try is soon.
The tank end cap was cut off with an angle grinder, as were the two door openings. I ground out 4 steel studs to weld to each side of the endcap and body to hold springs and retain the end cap. I can easily remove and reline if needed. Welded in the burner seat and 2 angle iron rails on the back opening to facilitate a piece of 1/2" Insboard to use as a door. Painted with black header paint that did not discolor after 2 hours of forging.
Total cost about $185. I found the Satanite to be fragile if anything rests on it at temp and I decided to reline the mouth of the forge with Bubble Alumina, which I found to be awesome for the floor and like concrete. I love that stuff so far. Any comments are welcome. Thanks.
Tony Z
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