Well, I have the o-1 ordered for making 2 BIG knives..18" OAL throwing/hunting knives. Only thing is, i gotta find someone who can HT a blade that long and temper to spring temper. Any ideas? My torch setup wont quite work for this project.

Taz Bring it up to temp in your forge and edge quinch it. Then take your torch and do your tempering.

I use an oxy/acet torch for my HT, no forge. These are BIG blades, .25x3.5x18" OAL, and they are for throwing knives, so they have to be spring tempered. The torch wont quite work on this, and it would take about an hour to bring them up to temp, let alone finding a tank big enough to quench them...

taz, did you ever find out how to heat treat those 18in. throwers? I am am having some 13 1/2" ones idm'ed out of 4140 and was trying to find out the best way to treat them. the guy that ordered yours must have been throwing a long time. I find the longer i throw, the longer my knives get.anyway got any thoughts that might help me out. thanks, Roc

How about getting a 4" pipe and shooting your torch into it. You should be able to contain enough heat to bring your blade up to temp. You just have to watch it closely to be sure your heat is even. This should be faster than trying to heat it up with the tip only. Temper it with the torch as you would any other blade.

Or if you have a big enough BBQ you can use kingsford charcoal. Just coat the blade with a thin layer of mud/fireclay (no more than 1/16") to keep the impurities out. You can set up a very cheap very effective large bed of charcoal briquettes with concrete blocks and expanded metal grating (that diamond mesh looking stuff). It's very easy to hit temps in excess of 1600F, and alot higher if you play a hair dryer over it. If you can get natural lump charcoal, it will be alot cleaner and hotter.