a few gas forge questions for Chilla and anyone else

Gday Charles, you mentioned that you have a gas forge, I think you said it was a venturi type. I'm interested in building one, but as yet can't decide between the
different designs. I've never used one so at the moment I'm still a little in the dark and confused with information overload.
What burner design did you use? did you use it as per the original design or did you modify it to suit the materials you had on hand?
How big is your forge body? Round or square? what type of insulation did you use and can you remember the name of the company you got it from?
Thanks mate, I'm sure I'll think of a few more as soon as you answer these. The pointers would be very much appreciated.
Regards Rusty_iron
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Hi Troy,
I've made one forge and I've bought one. I use the bought one now as I've tuned it properly and reduced the firebox so that I can forge weld.
I have made several types of burners, and bought a few also.
Okay quick and nasty is usually the best way to go.
-------------------------------------------------------------------------- I've designed my own burner, that is really easy to make and can be used venturi style or forced air.
Component list: -------------- Part A (flare) ------ 1 x 2 1/2" to 3" long of 1 1/2" stainless steel tube 1 x 1" pipe connector
Part B (gas accelerator) ------ 1 x mig tip 1 x brass tube to suit the mig tip about 4" 1 x brass adapter from brass tube to gas hose
Part C (burner assembly) ------ 1 x 9" piece of 1" pipe (burner tube) 1 x 3" piece of 1" pipe (air inlet) 1 x brass elbow to suit
Construction ------------ *Note: This is what I did, and it isn't rocket science :-)
Part A: Grind the pipe connector to just fit the stainless steel tube, and force fit into place (told you it wasn't rocket science).
Part B: Tap the brass pipe with a thread close to the mig tip, and screw into place. Silver solder to make a gas seal. Grind the mig tip so that it resembles a missile cone (this helps with air flow). *Note: I chose to shape the mig tip when the brass tube was attached because I have fat fingers. Silver solder the brass pipe to the brass adapter with a gas seal.
Part C: Drill a hole in the brass elbow to accept the gas accelerator, and silver solder into place.
Assembly and Tuning ------------------- If done correctly the gas accelerator should be poking out of the elbow. Take the air inlet and temporarily screw it over the elbow with the gas accelerator poking out. Gently bend the gas accelerator so that it is dead centre of the air inlet. Unscrew the air inlet and screw it on the other opening of the brass elbow. Screw the burner tube over the gas accelerator. Screw on the flare.
Done. An easy-peasy burner. The burner can be used as is or an air source can be screwed onto the air inlet.
*Note and warning: I got most of the burner components from Bunnings, and the non-brass components are galvanised. The pipe is fine, as it doesn't heat up enough to cause the zinc to burn off. However the pipe connector does give off zinc fumes until the zinc coating is burnt off so stay clear, it's safe after this period. If you can get non-galvanised fittings that's better of course.
--------------------------------------------------------------------
The commercial forge body is 12" x 6" x 2 1/2" (originally 3", but I put a hard fire brick floor in to raise the temperature. It's square.
The one I made is a little too large and I'm going to reduce it, it's round with a flat floor, I put some fibre board on the bottom, but need to reduce the firebox a little more. It's 12" x 6" x 7".. it's too big. I use castable refractories from Forseco, but a better way to go would be to use Kaowool and a zirconium based ir reflecting paint (supplied by Forseco), plus a hard fire brick for the floor.
You should be able to get Kaowool and fire bricks from a kiln or pottery supply place. BBQ supply shops, like BBQs Galore are a good place to look also.
Hope this helps a little.
Regards Charles P.S. I am experimenting on making a gas forge from a Milo tin. Mark I didn't work out, so I am currently working on Milo Tin Forge Mark II.
Rusty_iron wrote:

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