Question about Sharpmaker

[jokrswylde]

I read on the chris reeve site that he sharpens his knives at around 20 dgrs. But they recommend the sharpmaker to sharpen Sebenzas. My sharpmaker recommends sharpening @ 40 dgrs. Can anyone explain this discrepancy. I have just recently began sharpening my edc's myself, and I do not want to mess up a blade! Thanks

 

[Morgoth412]

I read on the chris reeve site that he sharpens his knives at around 20 dgrs. But they recommend the sharpmaker to sharpen Sebenzas. My sharpmaker recommends sharpening @ 40 dgrs. Can anyone explain this discrepancy. I have just recently began sharpening my edc's myself, and I do not want to mess up a blade! Thanks

Sharpen on the 30 dgr. setting on the Sharpmaker. That will work fine.
-Kevin

 

[jokrswylde]

The instructions for the sharpmaker say that the 45 dgr. is for a razor edge, are you saying the 30dgr. is better?

 

[Don Luis]

It´s a bit confusing but they actually mean the same thing. The 20 means 20 degrees per side (40 total), the 40 means 40 degrees total (20 per side).

Welcome to the forums.

Edited to add:

If I was a beginner I wouldn´t try reprofiling the angle of a Sebenza, I would practice first with some other knife, you may want to try with a simple knife , maybe one from the kitchen, see how much better it will cut if you thin the edge.

Basically a more acute angle in the edge will cut better, a more obtuse angle will be tougher. the ideal angle depends on the steel, the job to do, personal preference, etc. There are some people here who now a lot about this, hopefully someone will step in.

 

[Morgoth412]

The instructions for the sharpmaker say that the 45 dgr. is for a razor edge, are you saying the 30dgr. is better?

Depends on the steel and use.

For a folder with S30V the thinner the edge the better. (Up to a point) The 30 dgr will slice better, and the S30V is strong enough not to chip with this thinner edge.

A fixed blade that will see choping and heavy cutting would probably do better with the 40*, and a folder with say 440V, might chip less with a 40* as opposed to 30*

For your purposes of using an S30V folder I would go with the 30*.
-Kevin
Edited to add: Yea, I probably should have said the 40 = 20 too...

 

[smegs]

I read on the chris reeve site that he sharpens his knives at around 20 dgrs. But they recommend the sharpmaker to sharpen Sebenzas. My sharpmaker recommends sharpening @ 40 dgrs. Can anyone explain this discrepancy. I have just recently began sharpening my edc's myself, and I do not want to mess up a blade! Thanks

When you see degrees quoted as 40º, it usually means 20º per side. 30º would translate to 15º per side. Your sharpmaker instructions are giving the degrees as a whole. Two sides of a knife sharpened at 20º per side = 40º

 

[jokrswylde]

So, in general.. is it safe to assume that for steels such as 440c or aus-8 the 40dgr is probably better due to chipping etc. But for the sebenza, or knives with better steel, the 30 dgr is better.

I tried to search the forums, but it is not working for some reason, so I apologize if I am asking redundant questions. Thanks for all of your help!

 

[smegs]

So, in general.. is it safe to assume that for steels such as 440c or aus-8 the 40dgr is probably better due to chipping etc. But for the sebenza, or knives with better steel, the 30 dgr is better.

I tried to search the forums, but it is not working for some reason, so I apologize if I am asking redundant questions. Thanks for all of your help!

You are generally correct. I like to double bevel at 30 and 40 degrees. It produces a somewhat longer lasting edge and touch ups remove very little steel from the blade. It also makes cuts where the material passes the width of your knife a little easier. Cutting through a long length of carboard is an example. The shape of the blade is the biggest factor in those kind of cuts. I probably could and have gotten away with a 50º angle (2x25º) because the majority of my cuts are usualy small plastic tubing and stripping sheathing off electric cable. A steeper angle edge lasts longer and will overcome problems with lesser grade steel in a pocket knife.

 

[Esav Benyamin]

Chris Reeve recommends 20 degrees (40 inclusive) for a reason. His knives are working knives, and unless you have a specialized need for a very thin edge, you are better off with the Sharpmaker 40 than the 30. Besides, he uses a deep hollow grind, so even with a 40 degree secondary bevel, you are slicing with a fairly thin edge overall.

Like smegs, I also like the idea of sharpening the secondary bevel to 40 and then cutting back the shoulders of that bevel at 30. This will give you an effect similar to a convex edge, keeping your edge from being very sharp but the blade behind it becoming increasingly thick.