Oversharpening Knives. What happens?

bas

Joined
Dec 28, 2006
Messages
14
Hello all. I use a 204 sharpmaker to sharpen my knives,there is a bit of a learning curve in getting to learn how to use it but once you do get the hang of it you can really up the perfomance of blades. I sharpen mainly at 40 degrees 20 each side, & will start on 30 degrees 15 each side soon on a couple of higher end steels to see how much sharper they will get. My question is , once I have the knife shaving sharp on the fine rods at 40 or 30 degrees what happens if I keep going. Will I thin the blade out too much, roll the edge or will it crumble under the force of a cut. Or will it continue to get sharper & not turn into dust because the sharpening angle is either 40 or 30degrees. Im still a newb so any info would be great.:(

bas.
 
You are wasting blade steel to be honest.

Imagine if you lost 1/64 of an inch every time you sharpened your knife (my numbers are off I'm sure but, the point is made) how long do you think your knife is going to last ?
 
The only thing you will really do is take off more steel than you really need to. With that said very few people over sharpen. It is my beleif that most don't do enough grinding/sharpening to get an edge sharp. I think that is the most common problem and reason most don't get their knives sharp.
 
once I have the knife shaving sharp on the fine rods at 40 or 30 degrees what happens if I keep going.

You thicken the edge, reduce cutting ability, blade lifetime, impair further sharpening, etc. . Essentially you are just sharpening it again, so oversharpening it twice would be similar to efficient sharpening four times so you cut the lifetime in half. Of course the exact numbers depend on how much you oversharpen.

-Cliff
 
Just curious, Cliff, is there such a thing as overstropping a knife?
 
After getting a shaving sharp blade with the Sharpmaker, would stropping or any other method, make the blade significantly sharper?
 
Yes, you can overstrop a knife. Strops work like sharpeners- they wear away metal. Strops work slower than sharpeners, and if done properly will not make the edge thicker (because it should reform the primary bevel too). If you do sharpen correctly, oversharpening will just take away blade belly and the life of the knife (which is determined by how much hardened area is left and how long you want to carry around a knife with a blade that looks like a crude shank :D).

Sharpmakers are not the BEST sharpening method, simply one of the easier and more foolproof ones (and I would say one of the best/the best (for price) set-angle sharpening kits. Most knives already have edges set at those appropriate angles because they're efficient angles to use. The sharpmaker sharpens/creates two distinct bevels- the primary (30) and secondary (40). You could have a knife with only one bevel ground, but having two is more efficient because it reduces edge width, friction etc. Convexing an edge means that instead of having shoulders at the transition between the belly to the primary and the primary to the secondary you basically have a rounded bevel that has no shoulder (and thus has less friction). Full-convex sharpening blends the belly to the edge for an even more efficient (if ugly) blade. Stropping properly after getting your basic angles on a sharpmaker can subdue the bevel shoulders and make the knife sharper, but many people strop the wrong way and make matters worse.
 
Just curious, Cliff, is there such a thing as overstropping a knife?

Yes, you can abrade them more than necessary just like on a stone, and some stropping is just deformation based and that will weaken the edge. In short, just sharpen until the edge is formed and then stop.

After getting a shaving sharp blade with the Sharpmaker, would stropping or any other method, make the blade significantly sharper?

No.

-Cliff
 
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