Throwing knife temper

[Quasimorte]

I am going to try and make throwing knives from a couple of mill bastard files i have found and was wondering if i wanted a hard, medium, or soft temper on the steel? I know i have to soften the steel to a working level but can i harden it back up in a toaster oven? or should i soften it even further? I haven't started anything just yet, i'm still building my work bench but have all my tools together and was just wondering on spacific method.

thanks all

 

[polarbearforge]

While files wouldn't be my first choice for throwing knives, they will work. You can't harden them in the toaster oven, but you can temper them. In other words, you can soften them only. When I make throwing knives, I temper them at a higher temperature to make them tougher and not quite so hard. For 5160, I temper them at 475-500.

Jamie

 

[Stacy E. Apelt - Bladesmith]

Qusimorte,I don't know what your level of throwing ability is,but I have an idea of your knife making skills.Please read a book or two,go online and read some tutorials,and learn a bit about working with steel.You will avoid some mistakes that will cost you a lot of time (and maybe fingers) and you will not have to ask some of these sub-basic questions.
The toaster oven will not soften the steel,or re-harden it.You would have to heat it to around 1600F to do either.Once annealed (softened) the steel would have to be re-hardened to make it hard again.(Throwers made for just putzing around wouldn't even need hardening.)Tempering is done between 350 and 500 (for simple steel) to remove the brittleness after hardening.A high temper makes softer,but tougher steel.IMHO files would be the wrong steel for a thrower.Use a piece of 5160 spring steel.You can probably get it in annealed state from a spring shop in your home town.
Stacy