Damascus orientation for edge performance

JTknives

JTknives

Blade Heat Treating www.jarodtodd.com
Knifemaker / Craftsman / Service Provider
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Jun 11, 2006
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I have been wondering for a little while about Damascus pattern orientation and if it could be used to increase cutting performance. What got me thinking about this is how I sharpen my knives. I have started to sharpen my knives with a corse grit belt and then stright to the buffer. The edge seams to really cut meat like there is no tomarow and it shaves hair. So this got me thinking could you stack Damascus vertically so the layers are perpendicular to the edge. I am wondering if you selected steals that have different wear resistances would you get a simaler effect as sharpening with a corse belt. I'm thinking with a verticle pattern the buffer would buff away one layer more then another leaving a micro serration as long as you had a high layer count. Was just a thought.
 
Stop and think about it .... the layers are still perpendicular to the edge either way.

To explain it in very simple terms, look at a book. There are as many pages exposed on the side as there are on the bottom.

Micro serration is the effect that makes a 120 grit edge cut meat well, and can have the same effect with damascus. The steel choices are more of an effect than the pattern. It is the transition from one layer to a harder or softer layer that makes the aggressiveness.

The best pattern for an aggressive and consistent edge in damascus is probably a tight twist. This exposes the maximum layer transitions at the edge. Also, higher layer count gains more transitions.
 
What I was meaning was if you looked at the side of the blade the layers went from edge to spine kinda like a feather pattern. But the layers don't go from tip to tang but through the blade from one side to the other. Kinda like this
19.jpg
 
The above picture is way to corse of a pattern but gets the idea across. But like you said a very tight twist would do the same thing and be much easyer to make. My wife cuts a lot of chicken and I did a quick A300 gator belt finish with a green compound buff and she was blown away. The way it cut up a turkey we just butchered was unbelievable.
 
JTknives said:
What I was meaning was if you looked at the side of the blade the layers went from edge to spine kinda like a feather pattern. But the layers don't go from tip to tang but through the blade from one side to the other. Kinda like this
19.jpg
Click to expand...

Nice knife!

Hoss
 
That's not mine, just using it as an exzample for vertical layers. But yes it's a very nice lookin knife.
 
I love the Damascus on the blade. I have admired it for a while.
 
A ladder pattern gets the layers crossing the edge pretty well too.

Darcy
 
Interesting to find out that the effect on Damascus of blade change direction because of the layering is minimal. A known maker- sorry I can't remember his name - once wrote a few lines about the effect of making a blade across the grain on rolled carbon steel. His findings were that for sure the cutting results were extended 15% - 20%. I tried this on some ATS-34 and found that it certainly was true there also.
Frank
 
The Shun Dual Core knife series is designed to use Damascus steel for the micro serrations.
 
This is something that needs more testing.

This is more hype than anything perpetuated by some of the early makers of Damascus. The only time I've seen this effect is with a knife Wayne Goddard made that had some welding flaws. He didn't sell it but did some cutting tests with the knife.

Me and Larrin made and tested three test coupons, first one was Aebl, second was 154cm, and the third was 100 layer ladder pattern Damascus made from Abel and 154cm. All were given our best heat treatment and tempered to 60hrc. We used Spyderco's Catra testing machine and plotted the results.

The test coupon size was specified by Spyderco and an employee there responsible for sharpening test coupons did the sharpening.

The 154cm performed best because of its large volume and size of it's carbides. Plain aebl cut the least amount of the silica impregnated card stock. The 100 layer test mule did slightly better than the average of the two, showing that there is a very slight Damascus cutting effect.

The reason we chose this combination was for the contrast in the carbide size and volume. We don't think that Catra testing is the best for all steels, especially those with fine carbides.

Steel combinations like 1080 and 15n20 will be too close in structure and wear resistance to show any Damascus cutting effect at all.

Real life cutting will show no detectable cutting effect in most pattern welded steel blades. The higher the wear resistance of the steels combined, the more wear properties any blade will have.

Hoss
 
I've wondered for a while, would adding pure nickel in a twist pattern produce this serration affect? I believe Bill Moran used to make this claim to justify putting mild steel in his damascus (before total carbon diffusion in damascus was understood). Since carbon won't diffuse into nickel, it would certainly remain dead soft. I have no idea whether this would leave the hardened steel layers too weak at the edge, though.
 
I'll leave that last post up. But when I think a bit about how easy it is to bend a sanmai blade that has a hard core and soft cladding, I imagine this nickel/steel edge would probably roll the second it touched anything.
 
I remember reading Wayne Goddard saying that a fine ladder pattern on the edge cuts better than a straight laminate. It'd be worth investigating, but I doubt very much you'll get a huge jump in performance. More likely the way it's sharpened and thinness or thickness of the blade and proper heat treat will do more than the orientation of the layering. Or in other words, how many people will notice such a slight improvement unless your working on a slaughter house floor and have a steady stream of animals to cut up? I've seen knives go dull in the sheath just from the fine edge getting a little corrosion.

Not saying it shouldn't be investigated, just that I doubt much will come of it. But then who knows?
 
I cut alot of meat and that's what caused me to go after different edges. It's funny because I first tried super fine polished edges and it might shave hair but kinda sucks on meat. I started dropping down in finishing grits and things started getting better. Same knife just different belt grits befor buffing. Last sharpening was a rush job for my wife as she was butchering a Turky so I ran to the shop and used the gator belt that was on the grinder and gave it a quick buff. After she was done I asked her how it worked and she was amazed. I went and looked at the belt and it was a A300 gator, that's 80 grit or so thy say.
 
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