07-05-2017, 10:27 PM
(07-05-2017, 12:02 PM)Bobbo Wrote: ...I definitely do see more variation in edge sharpness readings after using coarse grits compared to finer grits. Interestingly enough though, having refined and improved my burr removal techniques though, I see very similar sharpness levels. I just don't see those low numbers as often along the length of a given and coarsely ground edge. I guess that's the "tooth" in a "toothy edge".
A toothy edge will give more varied sharpness readings than a smooth, polished edge. When you think about it, that makes sense. However, there is no reason why a toothy edge cannot be sharp. I routinely sharpen to 140g – 160g without jumping through hoops. For me at least, anything in that sharpness range is plenty sharp, and if I see those numbers I’m happy.
Coarser abrasives can produce some big, tough burrs that can be very malleable and difficult to remove. If you are not getting your blades sharp, or have readings varying more than 10g or 20g at most along the blade, I suspect that there may still be burr left in some areas. I suppose it’s possible that you are not evenly sharpening the entire length of the blade, but if you raise an even burr on both sides of the blade you should be fine.
If you hold the blade under a good light and carefully check out the edge both straight on and from both sides, generally a burr is actually visible with the naked eye. Tilt the blade from all angles, and if there is burr it will reflect light. A 10X loupe or a microscope is very helpful too.
What sharpness reading are you getting? What grit abrasive?

