Oil Quenched Handles

Crag the Brewer

Crag the Brewer

I make Nice, boring knives
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Knifemaker / Craftsman / Service Provider
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First off.... Merry Christmas, Everyone!!!

I normally make my blades out of higher alloy, air hardened steels....

I got a batch of 8670 from Bos. First time working with the steel. So far I like it. Another fun steel to work with.

But, I don't think I've made anything dipped before?

I almost screwed it up majorly, and wanted to make a post for the new makers.
Normally I cut around the perimeter of the handle the next day, after it is cured.

Look what I did.



You can see I cut into the steel.
Normally I rely by sound and feel, but lost track where the steel tang was.
On air hardened steel the tangs are at full hardness. I guess this isn't true for oil quenched blades?


Fortunately, it was on the underside. I only cut into the handle a little bit.... And it was for my wife.... I was able to work around it. But it really threw me for a loop, because I knew how hard the knife edge was, it took awhile to grind and sharpen. I was going crazy, then it dawned on me that it was dipped, and that must effect the blanks overall?








Thanks.
 
The handle should be mostly hardened as well if they were heat treated in a kiln, the only spot that may be slightly softer would be the very end of the knife where pliers or tongs held it but even then a steel like 8670 is pretty deep hardening and shouldn’t be able to cut it like that if it was properly hardened. I’d be calling Bos. and asking exactly how they processed the blades.
 
Joshua Fisher said:
The handle should be mostly hardened as well if they were heat treated in a kiln, the only spot that may be slightly softer would be the very end of the knife where pliers or tongs held it but even then a steel like 8670 is pretty deep hardening and shouldn’t be able to cut it like that if it was properly hardened. I’d be calling Bos. and asking exactly how they processed the blades.
Click to expand...

I could feel by sawing closer to ricasso area Was hard, but as you said at the rear/bottom was where I accidentally cut off.

The blade was definitely Very Hard, I just was surprised the butt wasnt. I'm sure the new bandsaw blade was a new blade No More.....
 
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Did you happen to notice an kind of transition somewhere on the tang where the scale gets less texture and more just dark? That would mean they didn't quench the tang in the oil.

I don't, simply because I don't have a deep enough quench tank (1 gallon paint can), but I would if I could because that oil line always has a warp. But that oil line would be a tell on wether the tang is hardened or not.
 
N.W. Gean said:
Did you happen to notice an kind of transition somewhere on the tang where the scale gets less texture and more just dark? That would mean they didn't quench the tang in the oil.

I don't, simply because I don't have a deep enough quench tank (1 gallon paint can), but I would if I could because that oil line always has a warp. But that oil line would be a tell on wether the tang is hardened or not.
Click to expand...
You would have thought that a Bos HT would totally submerge the knife.
 
Just a thought, perhaps the blank picked up a warp during heat treating (in the handle area) and they used a torch to straighten the warp resulting in a soft area where you cut it?
 
If Bos fixes a warp, there will be a “Q” marking the high point of warp. I know there is a maximum length of 12” tip-to-butt for oil quench. From your picture it appears over all length is about 14”. If you hit the handle some where from 2-3 inches from butt, that probably is your answer.
 
Yes, I think that's what this is .

Funny, I don't really see discoloration. It seems even .

Good to know about "Q" label
I have a couple Q's and everything looks nice and flat
 
The “Q” is marking high point of warp prior to straightening. It is a locator so the blade is straightened properly before returning it to the customer. I spoke directly with Paul Farner when I had some blades come back with a “Q”. He’s the one that gave me the info. I’m sort of surprised you weren’t informed about butt being soft. The 12” limit for oil quench is listed on Paul Bos Heat Treat page on Buck’s website. Buck’s Home page-About-Services-Paul Bos Heat Treat
 
J Lensmire said:
The “Q” is marking high point of warp prior to straightening. It is a locator so the blade is straightened properly before returning it to the customer. I spoke directly with Paul Farner when I had some blades come back with a “Q”. He’s the one that gave me the info. I’m sort of surprised you weren’t informed about butt being soft. The 12” limit for oil quench is listed on Paul Bos Heat Treat page on Buck’s website. Buck’s Home page-About-Services-Paul Bos Heat Treat
Click to expand...
I know there is a limit, and quite possibly I have known?
during the rush to cut out the handle, ALL gets lots in the excitement.
I definitely never knew about the Q info.

And I wish they sent paperwork back with the blades confirming they did what I asked. :)
 
I understand that. If anything that is one negative to utilizing Bos. You get an invoice stating heat treat and cost, but you don’t get a spec list, tested hardness, process used etc. The one thing I don’t know is how Bos straightens any warps.
I’m debating about sending my next batch back to Peter’s. I just know that Peter’s wasn’t a big fan of working with AEB-L/14c28n. I believe they changed their process, I’ll have to contact them and see what they have to say.
Good luck with the rest of your blades!
 
DevinT said:
The title should read oil quenched tang.

Side note: the edge of a kitchen knife should never be straight. There should always be a slight curve to it.

Hoss
Click to expand...

I have that large radius, it helps with rocking, chopping, and push cuts.

Person who has it says it's cutting great.....I'll keep you posted.
Thanks.
 
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