Thread: A couple of knife making questions

I've gotten the idea in my head to make a couple of slipjoint folding knives. I'm planning on starting with 3/32" O1 steel for the blades and springs, however I've never worked with stock that thin before. When profiling the blade, at what thickness should I stop before heat treating? Also, in some of the patterns that I've seen, there's a relief cut for the tang of the blade so that the liners won't leave visible scratches on the tang. Given that I'm working with hand tools, doing an exact relief will be hard to do. Could I not just install some thrust washers on the inside of the liners kind of like we do with razor scales?

I'd suggest a minimum edge of 0.020 inch. If you are starting with typical flat ground machinist barstock that has no forging history there will be a much smaller risk of warp during HT. It does not mean it won't happen but not as likely. Leaving a bit of thickness gives you some wiggle room straightening the edge if it does warp.

Washers are okay. You will need to recalculate blade thickness plus washers to determine the final thickness of the spacer at the butt of the knife, any pins or pivots used as standoffs (those bits that hold the liners/scales apart) in assembly and the final thickness of the spring (minus a little room to allow it to function as a moving part). Some of this depends on what method of assembly you are using (which guide/directions/author?).

But otherwise good luck.

Originally Posted by Mike Blue

I'd suggest a minimum edge of 0.020 inch. If you are starting with typical flat ground machinist barstock that has no forging history there will be a much smaller risk of warp during HT. It does not mean it won't happen but not as likely. Leaving a bit of thickness gives you some wiggle room straightening the edge if it does warp.

Washers are okay. You will need to recalculate blade thickness plus washers to determine the final thickness of the spacer at the butt of the knife, any pins or pivots used as standoffs (those bits that hold the liners/scales apart) in assembly and the final thickness of the spring (minus a little room to allow it to function as a moving part). Some of this depends on what method of assembly you are using (which guide/directions/author?).

But otherwise good luck.

Mike, do you think it would be a wiser alternative to use an end mill bit in a drill press to cut the relief versus using washers?

**EDIT**

Also, I was looking at my Case knife that I was going to use as a general guide for the general shape, and it doesn't have the reliefs and all-in-all it doesn't have many scratches at all.