Sharpening

[JLFonck]

Let me start first for thanking all who have previously shared their knowledge in the forum, I have already learned much on many knife related topics.

I am just starting learning about knifes and maintenance. Much of what I have learned, aside from this forum has been online at http://www.zknives.com/index.shtml ( the author I believe is a member of this forum.)

I am learning to sharpen and am not sure about the sharpening angle. I can find the knife technical specs that say what the blade composition is made of, but not the factory blade angle.

Example. I am sharpening an inexpensive Gerber folder (that I am willing to sacrifice for the sake of learning) using a "Smiths Precision Sharpening” set. This set gives you only two angles, 25 and 20 and a set of diamond bars from course to extra fine.

I reshaped the blade to 20 degrees and have actually attained a pretty good edge for a first attempt, just shy of passing the unassisted paper cutting test.

I believe the metal on this folder is S30V.

• 
  What was the blade angle new from the factory?

• 
  What damage have I done to the blades integrity by altering the angle to 20 degrees?

• 
  What angle should I use for a general purpose field knife?

NOTE: I tried to insert 2 pictures but couldn't quite figure it out, it asked for a URL but the pics are on my PC..

 

[Dan57]

What was the blade angle new from the factory?

Most factory folders have an edge angle of around 20 degrees.

What damage have I done to the blades integrity by altering the angle to 20 degrees?

None whatsoever. It was probably around there to begin with. And if it wasn't, then it should have been.

What angle should I use for a general purpose field knife?

20 degrees is fine for a general purpose knife.

I tried to insert 2 pictures but couldn't quite figure it out, it asked for a URL but the pics are on my PC..

http://www.bladeforums.com/forums/showthread.php/983468-How-to-post-pictures

 

[Bill1170]

To clarify one thing, that common angle of 20 degrees is PER SIDE. Added together the apex angle is 40 degrees inclusive. More acute angles will perform better (cut with less effort) but not be as durable. Higher end steels can take more acute angles without as much damage as cheaper steels. All of what I just wrote is gross simplification, but a good first approximation to what goes on at the edge of a blade.

 

[JLFonck]

Thanks... One more question, while sharpening does the stone stroke direction matter?

I have read it both ways... It is my general understanding however that a movement into the blade vs. outward may led to a rough (raged) edge?

 

[JLFonck]

These are post sharpening pitures

 

[Phydeaux]

Welcome to BladeForums!

There is a really good sticky at the top of this section (Maintenance, Tinkering and Embellishment) "What is Knife Sharpening About?". It has a lot of information in it. Read it, it will probably answer a lot of your questions. Dig around the forum and you will find all sorts of information.

There are many ways to sharpen knives. The method (freehand) that I use and seems to work for me is pushing the cutting edge across the stone like I am shaving a piece off of it. I see that you are already practicing on a Gerber, good idea. Get a cheap knife at a garage sale or thrift store and practice on that. Try some different things and see what works best for you. I've tried several different sharpeners and have always gone back to free handing, but that's what works best for me.

Ric