Heat treating furnace design.

[drogo]

why use a forge burner at all. if you are just trying to back temper(heat treat) why not use a burner for a gas grill. they cost less than making a burner and give off a large eaven heat.

just my .02

[ApprenticeMan]

This is for heating the blade to between 1500-1650, i don't think a gas grill oculd do that hehe. Good ideas Welder, i have to think about this one, build the prototype, all that hehe.

[Ian]

Why not make an electric heat treating oven? In fact I thought a lot of knife makers used a normal domestic oven to heat treat? If you can get the guts of one a simple kiln type box around lightweight refractory bricks would work well IMO. The refractory bricks are much better than the standard refractory in a cooker so it would probably get a lot hotter too, but remain 'dialable'. I've seen designs somewhere for a really nice electric furnace on the net. Think it was one of the british knife forums.

[welder19]

I don't know as though a grill burner would give the heat needed here but you could actually make a burner similar to them but much more high performance, you could make it the appropriate length for you "oven" and have it put out a lot more heat, larger holes more gas and more air.
You could definitely get a more even heat with that style burner, as far as them being cheaper.....that I guess depends on where you shop and how much you can scavenge up, I've build somwhere around 8-10 propane burners and have yet to spend a dime....not trying to brag or rub it in anyone's face. just making the point that if you srounge around enough you can do almost anything with very little or no $.

welder19

[case]

British Blades :: Custom Knives - How to Build a Heat-Treat Furnace - Page 1
here you go.

[HWooldridge]

Have you thought about a salt bath for both quenching and tempering? I'm told the results are very repeatable and reliable with almost no decarb issues.

[Ian]

Thanks for posting that Case, exactly the one I was thinking of

[dragonflySmithy]

One thing that you could do to help controll the build up of scale is to put a choke plate on the buner and run a slightly rich flame. For the little bit of scale that will form you can get most of it off by soaking it in white vinagar for a few days. then take it out and rinse it off with lots of water and a 3M pad ie green scruby.