Trad Gang
Main Boards => Hunting Knives and Crafters => Topic started by: Ragnarok Forge on March 06, 2011, 02:59:00 PM
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As usual I am fiddling around with new techniques and trying to learn new things. I was working on interupted quenching a set of skinning knives today and heard the dreaded tink on two seperate blades.
The technique I am working with is an interupted quench. The blades are made from modern Heller horse rasps I get from a farrier buddy of mine. The blades were triple normalized prior to quenching. I took the blades to nonmagnetic and held them at that temp for 2 minutes each. The blades were edge quenched in air temp water ( 65 degrees ) to black around 850 to 900 degrees, and then moved to finish quench in 130 degree canola oil. Heller rasps are 1095 steel. The bevels, and edges were even, I have the blades in the tempering oven and will take the scale off with vinegar to find out where the cracks occurred.
I have an armguard knife from a prior tink and now, two skinning knives that have small cracks in them. Being a knife maker so far has meant I never have one of my own knives to use. Every time I make myself a knife someone wants it bad enough I end up giving it up. I am going to work these knives up, put and edge on them and then use the you know what out of them to see what happens with them over time. I won't let anyone else have these since they are failed blades. I figure if nothing else I will get three shop knives out of the blades.
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I'm sure the moment the sound came was a little bitter after all that work... But knowing you, I'm sure you'll continue looking at ways to be better at what you do. I guess like you said, at least you have 2 more knives now.
I don't suppose your Heller rasps are Red Tangs? Those are the ones I have and have been wondering what steel they are. They 1095, too?
Jeremy
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Jeremy,
They should be 1095 if they are from Heller. You can try to find specific info on the Heller website. They may list that particular rasps steel type in a catalog. Another option is to contact Heller directly and they can tell you what the steel type is. They will either be 1095 or higher carbon steel.
I like to look at the positive side. As mentioned I have a couple of new shop knives. Plus I bet they work great despite minor cracks.
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sorry too here that! I would personally avoid quenching in water. Unless you are using a lower carbon steel, veg oil is actually a quite fast quench and you'll end up with a lot less tinks and warped blades. Most of the metal sights list 1095 as an oil quench steel. just my 2 cents.
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SRT Ben,
Thanks for that info. I have worked quite a few rasp and file knives sucessfully with canola oil. I am fiddling with an interupted quench to try getting good Hamon on my blades. From reading and research a water quench causes cracking when the steel is converting to full martensite at 500 degrees or so. Hence the interupted quench to oil at 850. I suspect that having the oil at 130 degrees made it to fast of a quench for 1095 to survive. My other blades were quenched in my goop.
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Not an expert on this at all, so I'll stay away from my opinion on what might have caused your tinks using water (more of an oil guy, but i think water temp maybe).
Glad to hear that you dont have a blade for yourself as a knifemaker either. Getting around to a dedicated "me" knife finally after all these years. This place is full of good info, so I'm sure you'll get a helpful response quickly.
Good luck, Nathan