Show off and talk about your Flat/convex grinds here!

N.D.

Well-Known Member
Hey! post em up if you got em! :bud:2thumbs

And try to remember . . . useless1

luvsite1Thanks to all who post here!

ETA Note: If you already have your pics posted else where on this site lets try to just post a link to the pics so the bandwidth stays reasonable for those W slower connections.

Thank you.
 
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I'll bite. Most of these have been posted here or elsewhere in the past, but here's a few. I do almost exclusively flat grinds....

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The above knife is forged W2 with redwood burl scales. Bevels were forged in, and the bevels and plunge were cleaned up afterwards. It has a full distal taper as well as a tapered tang. The hamon is a bit lower than I'd like, but the knife came out pretty good.



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The above knife is CPM154 stock removed with a full flat grind and desert ironwood.



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Another hand forged W2 with forged in bevels.



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Another CPM154 with flat grind and desert ironwood.



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Another CPM154 stock removal flat ground with desert ironwood.



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Stock removed Aldo's 1084 with full flat grind and mesquite. This is actually a combo of flat and convex, as the edge is rolled to a convex just before the final edge.



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The above pics show a military appreciation knife that was done for a contest put on by David at Great Lakes Waterjet. It's a variation of David's design from ATS34 with a full flat grind and canvas micarta.

Thanks for looking. I will say that I spent MUCH less time at the grinder when forging to shape and forging in bevels. However, I'm still figuring that art out. :D

--nathan
 
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Springing back to center.

Judging by your pics, I'd say you've got a pretty good handle on the forging in the bevels issue.
I like your lines, those W2 blades W temper lines both looked good to me. :D

I just thought I would ask you, if you don't mind.

Are you able yet to get a blade to flex over to 90* or any where near it and then to let the blade spring back to true W/O the blade taking any set at all?

Thanks for posting up those pics!
:bud:
 
ND, thanks for the compliment.

As to the blade flex, the answer in my case is "heck if I know." :D When it comes down to it, the style of knives I make don't have any need to flex to 90 degrees and return without taking a set. Maybe if I was making a blade with the geometry of a filet knife.... Most of my knives are 5/32" or 1/4" stock and don't lend themselves to that particular geometry. Heck, I wouldn't even want a knife make from 1/4" stock that could bend to 90 degress without taking a set.

I through harden my stainless blades and then draw back the temper with a torch. The same for many of my carbon blades with the exception of those on which I try to get a hamon. If I wanted to get a blade to bend to 90 degrees and survive, I'd make a long, thinly ground knife and harden just the edge. Even then, I'd expect it to take a set unless it had the geometry of a really thin kitchen knife or filet knife.

I don't place much stock in the bend tests used by the ABS. It's a good test to see if you understand how to heat treat to get a desired result, but the result they shoot for in the test insn't necessarily the be-all-end-all result, and isn't necessarily the best choice for many knives. And don't forget, even the ABS doesn't demand that the knife not take a set or even crack to some degree.

--nathan
 
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ND, thanks for the compliment.

As to the blade flex, the answer in my case is "heck if I know." :D When it comes down to it, the style of knives I make don't have any need to flex to 90 degrees and return without taking a set. Maybe if I was making a blade with the geometry of a filet knife.... Most of my knives are 5/32" or 1/4" stock and don't lend themselves to that particular geometry. Heck, I wouldn't even want a knife make from 1/4" stock that could bend to 90 degress without taking a set.

I through harden my stainless blades and then draw back the temper with a torch. The same for many of my carbon blades with the exception of those on which I try to get a hamon. If I wanted to get a blade to bend to 90 degrees and survive, I'd make a long, thinly ground knife and harden just the edge. Even then, I'd expect it to take a set unless it had the geometry of a really thin kitchen knife or filet knife.

I don't place much stock in the bend tests used by the ABS. It's a good test to see if you understand how to heat treat to get a desired result, but the result they shoot for in the test isn't necessarily the be-all-end-all result, and isn't necessarily the best choice for many knives. And don't forget, even the ABS doesn't demand that the knife not take a set or even crack to some degree.

--nathan

Ok thanks no critisism was intended, I was just curious; I don't think it's necessary, for a knife to bend to 90* and spring back on it's own W/O any set in order to be a good knife.

But I have seen some Katanas that did survive that test W a Diff. HT a Hammon and W/O edge cracking and returned to true . . I don't know how . . but I've seen it enough times that it's made me curious as to how . .

Great knives and thanks!:D
 
No problem, and no offense taken. The length of katanas def helps in spreading out the stress of the bend over a long space where a typical "knife" will run in the order of 7-8" and most times 1/2 that. With a differentially hardened longer knife (a "typical" knife, not sword) blade of proper geometry, you should be able to do a 90 degree bend without cracking through the edge, though your return to true will very rarely be 100%.

--nathan
 
Just a note. I am pretty sure that a traditional katana made from tamahagane would bend and take a set...and stay there until you bent it back. ;)
 
Nathan your grind lines are some of the best I still need to work on that but I dont do any flat grinds only hollow or convex and to keep the plunge like that is near impossible. Hollow grinding is what I like the most and Ill get better when I return to grinding steel. My neck is to sore to grind steel . Ive been finishing off some blades I did 4 months ago and when they are done I have no choice but to just take my time and grind out 10 blades or so. I dont do a few at a time cuzz I send my knives out to rob at ranger to heat treat.
 
No problem, and no offense taken. The length of katanas def helps in spreading out the stress of the bend over a long space where a typical "knife" will run in the order of 7-8" and most times 1/2 that. With a differentially hardened longer knife (a "typical" knife, not sword) blade of proper geometry, you should be able to do a 90 degree bend without cracking through the edge, though your return to true will very rarely be 100%.

--nathan

OK thanks for the info.? :D
 
Just a note. I am pretty sure that a traditional katana made from tamahagane would bend and take a set...and stay there until you bent it back. ;)

Yes Traditional steel most likely would as you say, bend and hold like Aqua Net, but who could really afford to buy and destruction test 1 of those?:confused:

I was referring to some various modern Diff. HT 'd (Hard back soft spine) W Hammon (Some were forged 9260) Katana's testing.

Today a smart user's Katana is all about
Cuts great, no bending 2thumbs if you stuff up a cut angle, or the proper follow through while the blade is in the cut, which would normally lead to edge chipping or Blade bending.:(

Even Masters have bent a few of the Traditional Tamahagane style blades, during Tamashigiri, so . . I prefer the new cutting edge metallurgy combined W the old Japaneses blade patterns, but W a spring like steel you don't even need a very thick blade any more which of course means you can have a slimmer cross section and that really helps to reduce the blades friction in the cut, and that means all else being equal a much better Gozo cutter! yea!
 
I'll Play,

Forged W-1.

Some HIGHLY sexual stuff in this thread.....

Hey no potty talk G rating here.

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Me likey! dancing dog
Great work, love the Hamon!

The pics a bit blurry so I cant really tell for sure but is that knife unsharpened?

That handle looks very interesting as well, do you maybe have some nice sharp close ups of that knife?
 
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Me likey! dancing dog
Great work, love the Hamon!

The pics a bit blurry so I cant really tell for sure but is that knife unsharpened?

That handle looks very interesting as well, do you maybe have some nice sharp close ups of that knife?

Good eyes, my friend.

It was unsharpened. More pics for you. It is sharp in these pics.

Thanks for the comments.

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Good eyes, my friend.

It was unsharpened. More pics for you. It is sharp in these pics.

Thanks for the comments.

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WOW! 2thumbs
Thanks for the clear pics.
That Hamon is really Bold great lookin Knife it looks like a real user, it speaks to me for some reason.

Couldn't get the second pic to fully load though, bad IC last coupla wks . . .

What kind of steel did you say that is?
How did you finish the blade?
 
N.D.,

This knife was forged out of W-1 and I used my super-secret, ancient Japanese clay mixture. Just kidding. It was furnace cement mixed with forge scale. I hand sanded to 600 grit and gave it a pretty heavy etch in Ferric and Flitzed the heck out of the hard part of the blade. Every temperline I do seems to require a different combination of polish/etch to look right. It really is hit or miss. This one went really fast, but I have spent 10 hours trying different things on certain blades.

-Nick
 
N.D.,

This knife was forged out of W-1 and I used my super-secret, ancient Japanese clay mixture. Just kidding. It was furnace cement mixed with forge scale. I hand sanded to 600 grit and gave it a pretty heavy etch in Ferric and Flitzed the heck out of the hard part of the blade. Every temperline I do seems to require a different combination of polish/etch to look right. It really is hit or miss. This one went really fast, but I have spent 10 hours trying different things on certain blades.

-Nick

2thumbs

Thanks that's awesome, that it came out so easy (subjective word) for you this time but I think I would get pretty aggravated W it if I couldn't just have a set way to bring it out, and just work on perfecting that 1 method, instead of a hit or miss type of scenario.
Either way though this 1 really worked for you!
I know it's a drop point, but how would you classify this knife; as a skinner or?...
 
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