Force air propane DIY

[Craftisahandjob]

So I started forging using a converted table top grill as a charcoal forge. Then upgraded to a propane tank propane fueled forge with a naturally aspirated burner. I'm looking to build another forge. I am seriously considering building a forced air propane burner for this new forge. I'm having a hard time finding clear plans for forced air burner builds but believe I can figure it out from what I've seen and read. My question is whether it's worth it? I'm hoping the forced air will lower my propane consumption. I can whip up a variable speed switch to a squirrel cage blower, but would probably start with just a set speed blower. My hope is to start forge welding. Given the size of the firing space I was thinking of using a 1/2 black iron pipe with a 3/4 BIP flare. I'm looking for adivce and more knowledge on the pros and cons. I'd rather not set up a basal valve and thermocouple or solenoid and all that stuff. Sorry for the wall of text. 

[Frosty]

Welcome aboard, glad to have you. If you'll put your general location in the header you might be surprised how many of the Iforge gang live within visiting distance.

A gun burner is plenty easy to build, a lot easier that a NA burner. It's just a gas supply installed in a pipe that leads to the forge with a blower supplying air. I suggest putting a 90* elbow between the gas jet and the forge, the turbulence of the turn does two things: first it helps mix the fuel air for a better burn and secondly it prevents a back fire is those conditions arise.

Increase efficiency? Heat output is directly determined by how much fuel air in the correct ratio you can get in the chamber per second. Properly tuned there is very little real difference between a gun and NA. About the only differences are: ease of construction, ease of operation and susceptibility to back pressure.

NA burners require more precision in the build and a little tinkering to get tuned but then it's just a matter of altering the propane PSI to change output, there is NO further ratio adjustments required. Gun burners are easy to make and rare better able to push the fuel air into a confined chamber but changing temperature REQUIRES you adjust both fuel and air taking practice. You have to tune the burner every time you want to change the output.

When you get down to it the job they do is the same for the same fuel unless you want to change the temperature in the forge, then you are burning fuel while you tune the gun burner and there is usually a little lag time. If you buy a gauge and keep a notebook changing temp with a NA burner is just a matter of turning the regulator to the desired psi and the forge temp will adjust.

I hope this is helpful. I make NA burners but have NO problem with guns, both do the job a treat once you know how to make them work for you.

Frosty The Lucky.