Cliff Stamp
BANNED
- Joined
- Oct 5, 1998
- Messages
- 17,562
I had been playing with edges left with belt finishes (slack belt sander), for some time, and wanted to verify I wasn't seeing the effect of the heating so I hand sharpened a couple. There was no difference in how they behaved, however I did find as a side issue about the most trivial way to sharpen a knife I have seen.
Take the belt and hook it over something, I was using a door knob. The belt then hangs slack as you hold the other end. You then take the knife and cut into the belt, alternating sides, and being careful not to cut your fingers off. You can pretty much ignore angle, to a very large degree as the belt just deforms to accept the edge profile.
If you go really high up you just put a slight secondary bevel, and if you go really low you round back the shoulder. However because the belt gives so much, the angle tolerance that is accepted is *far* greater than on a benchstone where if you go lower you make no effect. I just mark the bevel and take a few passes to get the right amount of curvature and just eyeball ballpark the remaining work.
Of course this will put a convex grind on the blade, and also scratches the hell out of everything. You can prevent the scratching if you tape up the blade, but this will gum up the belt. You could also give yourself a serious cut if the belt broke on the stroke towards you, however I tried to do this intentionally the other way and found it very difficult. However as with any sharpening, it is an inherently dangerous practice.
The belts are cheap, and you can of course change what part you are grinding on. You are looking and many sharpenings before you wear one out. You will just make it finer with each sharpening, but this will be a very slow process. It is also a *very* quick way to reprofile an edge. Using a 40 grit ZO belt strips metal off many to one times faster than using SiC lapping compound on a 220 SiC waterstone, which is in turn many to one over an x-coarse Diamond plate from DMT.
I have only tried this with coarse belts (100 grit AO and 40 grit ZO), but don't see why it would not work just as easily on finer ones.
Yvsa suggested a very similar method on the HI forum awhile ago with edge trailing strokes (he restored a Trailmaster). However I have found that into the edge works very well as noted in the above, and is many times faster. I press as hard as I can, and have seen no evidence of burr formation on D2 (Mel Sorg), Mission's Ti and A2, SOG's 440A and Beckers 0170-6C. Edges checked under magnification as well as through cutting.
-Cliff
Take the belt and hook it over something, I was using a door knob. The belt then hangs slack as you hold the other end. You then take the knife and cut into the belt, alternating sides, and being careful not to cut your fingers off. You can pretty much ignore angle, to a very large degree as the belt just deforms to accept the edge profile.
If you go really high up you just put a slight secondary bevel, and if you go really low you round back the shoulder. However because the belt gives so much, the angle tolerance that is accepted is *far* greater than on a benchstone where if you go lower you make no effect. I just mark the bevel and take a few passes to get the right amount of curvature and just eyeball ballpark the remaining work.
Of course this will put a convex grind on the blade, and also scratches the hell out of everything. You can prevent the scratching if you tape up the blade, but this will gum up the belt. You could also give yourself a serious cut if the belt broke on the stroke towards you, however I tried to do this intentionally the other way and found it very difficult. However as with any sharpening, it is an inherently dangerous practice.
The belts are cheap, and you can of course change what part you are grinding on. You are looking and many sharpenings before you wear one out. You will just make it finer with each sharpening, but this will be a very slow process. It is also a *very* quick way to reprofile an edge. Using a 40 grit ZO belt strips metal off many to one times faster than using SiC lapping compound on a 220 SiC waterstone, which is in turn many to one over an x-coarse Diamond plate from DMT.
I have only tried this with coarse belts (100 grit AO and 40 grit ZO), but don't see why it would not work just as easily on finer ones.
Yvsa suggested a very similar method on the HI forum awhile ago with edge trailing strokes (he restored a Trailmaster). However I have found that into the edge works very well as noted in the above, and is many times faster. I press as hard as I can, and have seen no evidence of burr formation on D2 (Mel Sorg), Mission's Ti and A2, SOG's 440A and Beckers 0170-6C. Edges checked under magnification as well as through cutting.
-Cliff
