Slipjoint heat-treating

[Lon Aguiar]

Yesterday I did the heat-treat on my first slipjoint. The blade and spring are O-1. Finished tempering the blade and spring and realized that I didn't get the tang on the blade up to critical temp. I was holding the tang with pliers and using a small paint can forge. Is this o.k. or do I need to re-treat the blade and harden and temper the whole thing?

 

[Shing]

I would reheat and reharden and temper. Otherwise the backspring could wear the tang prematurely. I heat treat mine by hanging it on a piece of thin steel wire so it dosen't absorb too much heat and use a blowtorch.

 

[Patrickknives]

I would start over, its not worth the risk to find its not heat treated. The knife could work very well with alot of snap and then strart to get sloppy, my first folder did that because I did not heat treat the spring properly. I hold the blade with a welders locking plier on the back of the blade. I usually dont worry about getting the back of the blade to temp since differential heat treatment will help make the blade harder to break. Usually a small blade you can get hot with a torch direct, were you trying to measure the temp in the can??

 

[Patrickknives]

One more note, make sure you temper the spring different than the blade. The blade will be tempered at about 325-400 F and the spring at about 900. There are some posts showing how to do with torch and watch color.

 

[Lon Aguiar]

Thanks for the help guys. I am doing the heat-treat over. Tempering it right now. I hung the blade on a wire and turned the forge on end so it was vertical. I was surprised that I was able to get the spring tempered on the first try. I used a torch and got it to a nice bright blue. I did it three times so hopefully it won't break.