Best blow torch

[SteelSlaver]

Lay a bed of charcoal down, then lay a piece of 2" steel pipe that will hold the blade of your knife on the bed in such a way that you can grab the tang with some tongs or pliers. Now lay a second piece of pipe down so that it points at the first at about 45 degrees with one end near the tang end of the 1st pipe and the other end on the side of the BBQ. Cover the first pipe and that end of the 2nd with charcoal leaving the tang end open. Light the charcoal and when it is going good take the wife's hair dryer and blow down the second pipe. Place your knife in the first pipe (muffle) when it starts to get red. Pull it out as it gets red and keep checking with magnet. If you are using 1085 it should work alright. 1095 you best put it back in after the magnet doesn't stick and go up what you hope is another 75-100f before quench.

 

[russianpolander]

I've never tried this but a friend at work told me this: Punch about twenty holes in the bottom of a 5 gallon steel bucket and fill it with any charcoal. Drench it with a quart of kerosene and light it. When it is white hot plunge the knife in fully and heat 1095 'til it is red then quench in some old transmission fluid. Temper in an oven at 400f for 20 minutes. What do you guys think?

 

[tryppyr]

I think the OP is determined to use his blow torch, so he'll probably modify anything you say to include it in the solution, no matter how superfluous it is in the end.

 

[SteelSlaver]

That method would probably work fine for making the heat. The 1095 till red and then quench in ATF is really sketchy though. It will turn a red well before 1500 and stay a red until well past. Depends on what red and under what light you look at it. Canola would be better than old ATF just because of the health issues of smoking ATF which I started with. Placing a muffle in the bucket with the charcoal and cutting a hole near the bottom to accept another piece of 2" pipe for blowing air in would also work. When the magnet don't stick give it another minute and a couple subtle shades of red then quench.

20 minutes at 400 is not near long enough. 2 times for 2 hours at 400 would be much better.

The thing about a small propane torch is a bigger piece of steel will give off the high heat faster than you can put it in. Getting it hot is not a problem, getting it to an even 1500f is. Only way a small torch is going to make it is with some kind of heat dam/ insulation to help you out.

 

[Atlas Knife Company]

A standard propane plumbers torch (propane/air) reaches a bit over 2000F.
A propane oxygen torch reaches 2900F.

Don't you mean C instead of F on those temperatures? If not, then it wouldn't be possible to forge weld in ANY propane powered forge.

The maximum adiabatic flame temperature a propane torch can achieve with air is 2,268 kelvins (1,995 °C/3,623 °F). Some propane torches are also used with a tank of pure oxygen to achieve a flame temperature nearing 3,095 kelvins (2,820 °C/5,110 °F).