Sharpen a knife.

[DerekH]

i'm also new to stropping. thanks for the tips. i've enjoyed your posts in general.

to clarify, instead of altering directions, could you not just strop at 90 degrees to your blade in sections of 1 1/4" (or whatever the width of your strop)?

You most definitely can, but I find it goes a little quicker to work it in alternating directions

 

[sam.t]

Thank you,

 

[tueller]

You most definitely can, but I find it goes a little quicker to work it in alternating directions

Thx for the great thread. As for alternating the stropping direction, should the same be done on stones when sharpening into the stone like you directed? What about if you start on stones and finish on a strop? Whould you be alternating directions on both?

 

[DerekH]

Thx for the great thread. As for alternating the stropping direction, should the same be done on stones when sharpening into the stone like you directed? What about if you start on stones and finish on a strop? Whould you be alternating directions on both?

I will usually just alternate during the stropping. As far as on a stone, I imagine the same would apply, but I usually don't finish on a stone so I can't say for certain.

 

[zpstl321]

Just a note for those using Bark River Stropping Compounds...The White and Green are reversed, the white is finer. I've used both teh polishing compounds and the stropping compounds and found they both work fine. The stropping compounds are more chalky and more aggressive, so they work a little faster.

 

[Gottmituns78]

This is the best sharpening thread/ tutorial I have ever read bubba! I started on a 5.97$ norton course/fine stone. Thank you for the time and thought that you have put into this!!! Someone needs to mAke this a sticky!

 

[cschol]

This thread is Sticky worthy.
nice work with the illustrations.

 

[DerekH]

Thanks for the kind words everyone, but I can't take credit, almost everything in this thread was learned from the great people here. Moose, Jerry Fisk, Tradewater, Gutsy, those guys are the ones that I think I learned the most from. Like it has been said, we got a fantastic group of people here.

 

[DerekH]

So, during the course of me and Pointy's obsessive quest in the realm of sharpening, we hit a very distinct problem. When you sharpen a v-grind, determining the angle is a fairly simple process, especially if you have a sharpening system like a KME or other that shows what angles you are sharpening an edge at. So, how does one determine the angle of a convex edge?

We have a working theory that seems to have merit, so I figured I would post it up here. The difficulty in establishing the angle of a convex edge is that quite simply there is no one single answer, the edge is curved convexly and this means that something as simple as laying it on a KME won't quite work.

So how do we do it? For our working theory, we have to first ask what is accomplished by the edge angle? The edge angle of a knife is the angle at which the very apex will do what a bladed instrument is designed to do; cut. We sharpen the apex by removing material and refining the face such that the edge apex is in fact "sharp". We do this with a convex edge by dragging the edge away on a somewhat yielding material such as leather.

And here's the answer; what happens when you go the other way? That simple question was the single item that changed our entire outlook on developing a method of determining the angle of a convex edge. What angle does the edge begin to cut into material? The angle where the edge begins to dig into the material. On a convex edge you can find this by slowly rotating the knife until the point at which it just begins to cut on something flat. Once you hit that angle, you have thus determined the angle of your edge (in theory at least).

See, the only part of the edge that matters is the very, very edge, and that is the part that really determines what the angle could be, so if you rotate your knife on the convex portion whilst cutting it towards the material, when it catches, that is your angle.

If you knife has flats, you can use an angle finder to see just what that angle is, (angle finder shown below) as the flats will be parallel to the centerline that you are using to determine your actual angle.

Got mine at Lowe's this morning. So far, the theory seems to work. Thought I might toss this out there and see if any like-minded individuals might be willing to undertake the same experiment to independently verify our results.

 

[daizee]

Neat idea, Derek. Gotta make sure you don't shove your blade too deeply into your stropping material though, or you'll get false positives. And the compliance of stropping materials varies so widely, it may be tough to pin this down.

 

[TheModernNeanderthal]

So, during the course of me and Pointy's obsessive quest in the realm of sharpening, we hit a very distinct problem. When you sharpen a v-grind, determining the angle is a fairly simple process, especially if you have a sharpening system like a KME or other that shows what angles you are sharpening an edge at. So, how does one determine the angle of a convex edge?

We have a working theory that seems to have merit, so I figured I would post it up here. The difficulty in establishing the angle of a convex edge is that quite simply there is no one single answer, the edge is curved convexly and this means that something as simple as laying it on a KME won't quite work.

So how do we do it? For our working theory, we have to first ask what is accomplished by the edge angle? The edge angle of a knife is the angle at which the very apex will do what a bladed instrument is designed to do; cut. We sharpen the apex by removing material and refining the face such that the edge apex is in fact "sharp". We do this with a convex edge by dragging the edge away on a somewhat yielding material such as leather.

And here's the answer; what happens when you go the other way? That simple question was the single item that changed our entire outlook on developing a method of determining the angle of a convex edge. What angle does the edge begin to cut into material? The angle where the edge begins to dig into the material. On a convex edge you can find this by slowly rotating the knife until the point at which it just begins to cut on something flat. Once you hit that angle, you have thus determined the angle of your edge (in theory at least).

See, the only part of the edge that matters is the very, very edge, and that is the part that really determines what the angle could be, so if you rotate your knife on the convex portion whilst cutting it towards the material, when it catches, that is your angle.

If you knife has flats, you can use an angle finder to see just what that angle is, (angle finder shown below) as the flats will be parallel to the centerline that you are using to determine your actual angle.

Got mine at Lowe's this morning. So far, the theory seems to work. Thought I might toss this out there and see if any like-minded individuals might be willing to undertake the same experiment to independently verify our results.

Makes sense...

Your essentially moving the tangent to the curve at a given point along the curve till you reach the apex. There is math in there somewhere.

 

[DerekH]

Neat idea, Derek. Gotta make sure you don't shove your blade too deeply into your stropping material though, or you'll get false positives. And the compliance of stropping materials varies so widely, it may be tough to pin this down.

I've been doing this on wood and just shooting for the beginnings of cutting, so very little pressure, and several different attempts to verify the actual angle.