Hollow grinding a U2 - need maker

[Kim Breed]

Can I use that cinder block in my next spec sheet. I have a new laminate folder from William Henery that has an edge hardness of 65 RC. Should I use a 2 x 4 or a hammer to knock it through.

 

[Cliff Stamp]

why so slow?

I live in the boondocks, there isn't even a post office in the town where I live, I have to drive to the next one.

...had a little chipping

Yes it has little flexibilty at full hard, it doesn't work well for bone contacts in high cutting profiles. No ductility so it cracks trivially if the edge is loaded sideways. I have used them on poultry and red meats, but I crack the joints and cut only tissue, you have to go fairly slow unless you have a lot of experience.

you can't have it work right at full hard..

Depends on what you want it to do. Mine is excellent on ropes, paper, cardboard, foods, plastics, woods, etc. . If you wanted to cut metals and bones it would do that well too, but you would need a profile which would prevent chipping, or course this would lower the cutting ability and you would be better off with a tougher steel for that type of work.

Of course for the edge profile I described no steel will handle that type of work, the softer steels will just ripple. With the edge this thin you can't subject them to even light lateral strain, you could likely break the edge by trying to force it through the end of a coke bottle unless the load was perfectly perpendicular. That isn't a concern for me though, I carry more than one knife which allows high levels of niche optomization.

Ok if you want to get really specific you can cut metals and bone but you have to be very careful not to induce any laterial loads. I have used them to carve bone into needles and such, but you have to use high angles of attack and watch the pressure because the edge is fairly weak at 0.005" and again full hard steels have next to zero ductility. On hard materials like that you have to cut small amounts. The edge retention is very high if you do that because the wear resistance and deformation resistance is high.

-Cliff

 

[howiesatwork]

One thing I am not grasping.
An edge of .005"?
Would it not be extremely dull at .005"?
I like to sharpen mine closer to .000001", or less...
By the .005", you mean how far up the blade from the edge, which should be 0.0"...?, or is this the presharpened profile size??
If so, I would not call it a knife, but a thin scalpel.

 

[Dan Gray]

I live in the boondocks, there isn't even a post office in the town where I live, I have to drive to the next one. -Cliff

how slow is your car?

Yes it has little flexibilty at full hard, it doesn't work well for bone contacts in high cutting profiles. No ductility so it cracks trivially if the edge is loaded sideways. I have used them on poultry and red meats, but I crack the joints and cut only tissue, you have to go fairly slow unless you have a lot of experience. -Cliff

sound like a chance to brake it each time you use it. why bother?

If you wanted to cut metals and bones it would do that well too, but you would need a profile which would prevent chipping, or course this would lower the cutting ability and you would be better off with a tougher steel for that type of work.

Of course for the edge profile I described no steel will handle that type of work,
-Cliff

there you go , a Tougher steel needed

. With the edge this thin you can't subject them to even light lateral strain, you could likely break the edge by trying to force it through the end of a coke bottle unless the load was perfectly perpendicular. -Cliff

i NEVER WOULD would do that we pay 5 cents for the deposit on the coke bottles here , and they don't slab up good for the freezer anyway

but you have to use high angles of attack and watch the pressure because the edge is fairly weak at 0.005" and again full hard steels have next to zero ductility. On hard materials like that you have to cut small amounts. The edge retention is very high if you do that because the wear resistance and deformation resistance is high.

-Cliff

sounds like a time bomb waiting to happen to me ,, Cliff.

yahup 154CM .. sounds like the steel you need or go the other way
to push limits , say Bronze ,, why not,, I know it will kill Pepsi bottles

 

[Steve Hayden]

Hell I can kill Pepsi bottles by whackin' 'em with a lead-filled snowshoe.

 

[Dan Gray]

Hell I can kill Pepsi bottles by whackin' 'em with a lead-filled snowshoe.

but is it still sharp?

 

[Dan Gray]

Can I use that cinder block in my next spec sheet. I have a new laminate folder from William Henery that has an edge hardness of 65 RC. Should I use a 2 x 4 or a hammer to knock it through.

Kim
where the 2x4 is softer,, use that first, then the hammer..
compare the dents in the 2x4 to the hammer dents then average it out
you'll come close to the dust dent test of comet lulu that made the tide rise 4" feel higher here in Maine in 1909 I saw it happen.. the dent was .004
I had to wait
after the frost of 1910 to get a real reading, man I got cold as hell that winter watching it,, I forgot my coat in the buggy.

 

[Tom Buchanan]

hello dan, i know what you're saying on the winter.i spent 2 yrs up at caribou in the fifties.colder than a welldiggers butt in the klondike.

 

[Dan Gray]

hello dan, i know what you're saying on the winter.i spent 2 yrs up at caribou in the fifties.colder than a welldiggers butt in the klondike.

BRRRRRRRRRRRRRRRRRR and those wells dig hard too

 

[c.m. arrington]

Would a forged Pepsi bottle be better than a ground one? Would a 550 cord wrapped handle be better than a full tang handle? Hmmmmmm, I wonder......

 

[Dan Gray]

Would a forged Pepsi bottle be better than a ground one? Would a 550 cord wrapped handle be better than a full tang handle? Hmmmmmm, I wonder......

What
you meen Pepsi bottles arn't forged

 

[c.m. arrington]

Well, down here they're known by the native name of "Ko-kolas". The earliest known examples were knapped. This thread has gone way OT.

 

[Dan Gray]

This thread has gone way OT.

nope there was mention of the knife test through the bottom of a coke bottle by Cliff and it's his thread..
Testing a razor blade wasn't it? or was it making one

 

[Steve Hayden]

but is it still sharp?

No, but the edges didn't chip.

 

[Cliff Stamp]

By the .005"

The thickness of the edge behind the bevel.

sound like a chance to brake it each time you use it. why bother?

Because it is the optimal profile for cutting ability and hardness for edge retention if you know how to use it without overstressing the edge.

It isn't the geometry and hardness I would use for everything, the scope of work is reduced of course but I carry more than one knife.

-Cliff

 

[Dan Gray]

It isn't the geometry and hardness I would use for everything, the scope of work is reduced of course but I carry more than one knife.

-Cliff

so cliff
how would you test this knife? , from the maker that you got to do it for you? it bothers me that you won't say who you got to do it.
we all want recognition for our work,, so it makes me wonder and I'm sure others do to. why the secret?
if he is good enough to do this grind he'd be known to someone..
don't you just hate secrets? we tell you all you want to know right.. ?
come on fair is fair...it only makes us wonder if you do have a maker doing it? it does me anyway,,
how about you guys??

are you wondering too?

 

[Arthur Washburn]

I'm wondering why everyone keeps feeding the Troll.

 

[Gossman Knives]

Please enlighten me or humor me.
Scott

 

[Cliff Stamp]

how would you test this knife?

Cut plastics, cardboard, woods, plastic, foods, etc., normal everyday materials in the manner described in the above, same stuff I always do. I am interested if the steel can actually function at all at very low angles, ~5 degrees or so. Assuming it can, after doing the above I'll slowly extend the scope of work to evaluate its niche in that profile.

it bothers me that you won't say who you got to do it.

That was another joke, it is Tom Krein. I just asked him to grind it as thin as he can using the above spec's are rough benchmarks. I would not hold him responsible for the performance, he is grinding to my specifications. The steel may not even hold at that thin a profile, it might just come apart on the wheel. I don't care about that either, the information is worth the knife.

I also told him not to sharpen it, and I don't care about the finish, I can sharpen the knife, and want to know how it responds personally to honing anyway. I also don't care about any scratches to the existing primary grind ourside the hollow, cosmetics are meaningless on a working knife, don't care about grit in the lock, scuffs to the handle, etc. .

So don't use this to judge the quality of his finish work, his ability to sharpen knives, or his judgement on geometry and scope of work. In fact don't use it to judge his work at all, buy one of his knives for that, they look pretty good to me. This just shows his willingness to experiment which is one of the qualities I look for in makers, probably the primary one, you can't learn if you never try something new, without the possibility of failure there is no chance for innovation.

-Cliff

 

[Dan Gray]

This just shows his willingness to experiment which is one of the qualities I look for in makers, probably the primary one, you can't learn if you never try something new, without the possibility of failure there is no chance for innovation.

-Cliff

been there what's why the questions.
the blade will have stresses at full hard and I believe it will warp and warp bad at .005 I hope it don't bite him on the wheel.

you never asked if anyone has tried that, you asked if anyone would do it for you.. you had all the answers and not enough questions.
that last time I did something like that it cost me a $100.00 wheel
and almost a finger.

cliff when you joke let us know you are joking so we know OK

rough benchmarks you were pretty to what you was looking for.
how rough is rough when you quote .005 to a custom knife maker anyway?