After having to relocate my shanty town style shop of tarps and makeshift work benches I have finally spent the required time to have a forge that isn't so ghetto. I used an old 20lbs propane tank and some various scrap. Angle steel from a bed frame, barbq grill, rebar, a bit of sheet metal and some 1/4 round. The burners are 3/4 pipe in 6" lengths into floor flange. (No flared end or nothing) an 1 1/2 reducer to 3/4 and some 1/8 Id pipe with a 5/64 hole drilled in it for gas. There are many places to get info for making these forges and burners and after trying what seemed like every variation possible, I have realized that if you put gas down a pipe through a small hole at a wide ranges of psi and stuff extra air into them you get results. My point is there are lots of things that work, some more efficient than others but don't be discouraged when building a forge that doesn't work. Some advice though, now that I have tried so many things I bet I have spent the equivalent time and money as buying one outright from a reputable company. Having said that its totally possible to make a forge for $50. I'm sure some would rather not see blow dryers in use but it is what it is for now. They work great and you can choke the intake with a piece of tape,

This is a video of mine running at one psi, then I turn it to two psi and turn the air up. With no choke.

trim.r2KEcD.MOV

Good looking forge. (Wasn't trilled I had to save file to puter before I could play it but maybe its a limitation of Win 8) ;) and looks HOT :) But, WOW those are some big gas orifices!! At 1 psi, it doesn't leave much lea way to idle it down for a good long soak. Outside of heavier pieces could reach welding temp before inside gets to forging temp. I have a forced air forge I built and even with a 1.25" burner pipe, I'm only running a .05 something (Forget the letter size) gas orifice and at 5 psi I can burn up steel reeeeal fast :D

You're right. It's super hot super fast. I may make a very small forge with one burner and a smaller oriface for tempering and such. Thanks for pointing it out. :)