I'm a hobby maker with about 20, or so, knives made so far all using O1 steel(some of my work....http://knifedogs.com/showthread.php?t=3466) .
While I believe my heat treat/temper process has been adequately producing usable knife blades, I don't know that to be the case.
Because my wife is an instructor at the Canadian Coast Guard College here in Sydney, I have been able to use some of the resources and equipment housed in their Mechanical Engineering building. There they have a rather large heat treating oven suitable for anything up to 36" in length(big oven!).
My process has been to:
- preheat the oven to 1350F
- bake the knife blades(I've done four at one time) until critical is reached(non-magnetic)..... approx 20 minutes at temp.
- quench in heated used motor oil(being careful to move the blades back and forth for 10-15 seconds)
-immediately run to the College's kitchen where I place the knives in a preheated 350F oven for one hour.
There... that's my process.
The resulting blades will then be hard enough to not scratch when worked w/ a file, and the grinding sparks will be "whiter" then those from the annealed steel.
I have not done a 90 degree blade bend test, or had the hardness accurately checked.
From this description, am I on the right track?
I have read of the process of "thermal cycling(??)" by heating the blades to critical temp then cooling to room temp. Do I need to be doing this w/ O1 steel?
What more, or different should I be doing to produce a superior blade?
While I believe my heat treat/temper process has been adequately producing usable knife blades, I don't know that to be the case.
Because my wife is an instructor at the Canadian Coast Guard College here in Sydney, I have been able to use some of the resources and equipment housed in their Mechanical Engineering building. There they have a rather large heat treating oven suitable for anything up to 36" in length(big oven!).
My process has been to:
- preheat the oven to 1350F
- bake the knife blades(I've done four at one time) until critical is reached(non-magnetic)..... approx 20 minutes at temp.
- quench in heated used motor oil(being careful to move the blades back and forth for 10-15 seconds)
-immediately run to the College's kitchen where I place the knives in a preheated 350F oven for one hour.
There... that's my process.
The resulting blades will then be hard enough to not scratch when worked w/ a file, and the grinding sparks will be "whiter" then those from the annealed steel.
I have not done a 90 degree blade bend test, or had the hardness accurately checked.
From this description, am I on the right track?
I have read of the process of "thermal cycling(??)" by heating the blades to critical temp then cooling to room temp. Do I need to be doing this w/ O1 steel?
What more, or different should I be doing to produce a superior blade?
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