Convex Edge

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d762nato

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What makes the convex edge so great? Is it considered the best? Does Busse convex any knives, or just certain models?
 
Convex geometry improve cutting capabilities since the area of contact between steel and cutted material is reduced to a line (virtually). A smaller contact area results in smaller friction.

Also a convex edge is easier to sharpen.

Some interesting info here:

http://www.barkriverknives.com/convex.htm

Most of Busse knives don't have a convex edge. Among the recent models the NMSFNO and the Sarquatch do.

Some old school Busse blades have an asymmetrical edge. Those knives are flat ground, with complete symmetry right to the edge bevel and this is where the Asymmetrical work is done. With the blade edge down the left side is flat ground and the right side is convex ground.

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http://www.sosakonline.com/index.php?option=com_content&task=view&id=80&Itemid=35
 
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Thakyou for the link Sir,:thumbup: so I guess the convex edge is the ultimate knife edge.
 
d762nato said:
Thakyou for the link Sir,:thumbup: so I guess the convex edge is the ultimate knife edge.
Click to expand...

Having showed all the pros I would point out one thing. Convexing an edge that wasn't born convexed will reduce material thickness near the edge.
Cutting ability will be improved but the edge itself will be weaker.

convexs.png
 
Great diagram on blade profiles, I see what you mean. It actually thins the overall thickness of the metal.
 
Some Busses have a convex primary grind. The Sarsquatch and NMSFNO have that, as does the new Bushwacker. There are probably others. I just happen to own those models. All my Busses had a bevel final edge except the Killa Zilla and Sarsquatch CE, which have the convex edge. I think all the Competition Edition Busses had the convex edge. That should tell you something. If you look at the illustrations in Black Diamond's post, notice the smooth shape, much like a modern rifle bullet. Just as the modern bullet goes through the air efficiently with minimal resistance, so the convex edge cuts through materials more efficiently than the bevel edge. Convex edges are plenty strong when properly ground. From years of chopping and cutting experience, I can tell a big difference in chopping performance when a factory bevel edge is smoothed out into a convex one. When I blend a convex ground primary grind into a convex final edge as I did on my NMSFNO and BWM, I get outstanding chopping performance.
 
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That's good to know Horn Dog Thanks for all the Imformation. Did busse make just the one model of the sarsquatch. I mean are they all the same thickness,length, model?
 
d762nato said:
That's good to know Horn Dog Thanks for all the Imformation. Did busse make just the one model of the sarsquatch. I mean are they all the same thickness,length, model?
Click to expand...

They are all 3/16" thick with 7" blades. I got the CG and the CE. Here you see my stripped and convexed CG along side the CE model.

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How do like the sarsquatch, I guess thats a dumb question since you have two of them.
What I'm asking is how do they compare for chopping and such. What is your primary use, and is it a heavy duty knife.
 
d762nato said:
How do like the sarsquatch, I guess thats a dumb question since you have two of them.
What I'm asking is how do they compare for chopping and such. What is your primary use, and is it a heavy duty knife.
Click to expand...

The broad bladed Sarsquatch is a fine knife for camp or trail. It is ligher than some blades due to its thinner stock. Some heavier knives can out chop it, but the Squatch chops just fine. It also excels at slashing limber grasses and brush like a mini-machete. I modified one of mine into a SAR Bowie, just to have a bit more point, but it still chops well enough for such a light, easy carrying knife.

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Man Horn Dog, your pretty talented with the knife grinding and restyling blades.:thumbup:
That looks like a new sarsquatch bowie design. Sweeeeet!
 
Thanks. I think I did the first one, but Ban did the prettiest one I've seen. As you can see, I left the scales on and did not bother to sand the flats on the ricasso or pommel. It is one of my favorite Busses.
 
Back on topic, another Busse that comes with the convex grind is the super heavy duty NMSFNO. It is the most potent 8" chopper I have ever used. I stripped mine and blended the factory convex primary grind to a full convex zero edge. It's a lot heavier than the Sarsquatch, but this is my ultimate camp knife.
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