Originally Posted on by firstname.lastname@example.org
Below is an article by a sharpening expert, Joe Talmadge. In my own findings, a highly polished edge is not only not needed very much, in most cases it actually hinders the cutting ability of the blade. High polish is for push cutting (i.e. “pushing” through a cut vs. “slicing” through a cut) such as straight razor shaving or wood carving. It has very limited uses. In most other situations, you will want and use a toothier edge.
” Many treatises on sharpening tend to focus on getting a polished, razor-like edge. This is partially the fault of the tests we use to see how good our sharpening skills are. Shaving hair off your arm, or cutting a thin slice out of a hanging piece of newpaper, both favor a razor polished edge. An edge ground with a coarser grit won’t feel as sharp, but will outperform the razor polished edge on slicing type cuts, sometimes significantly. If most of your work involves slicing cuts (cutting rope, etc.) you should strongly consider backing off to the coarser stones, or even a file. This may be one of the most important decisions you make — probably more important than finding the perfect sharpening system!
Recently, Mike Swaim (a contributor to rec.knives) has been running and documenting a number of knife tests. Mike’s tests indicate that for certain uses, a coarse-ground blade will significantly outperform a razor polished blade. In fact, a razor polished blade which does extremely poor in Mike’s tests will sometimes perform with the very best knives when re-sharpened using a coarser grind. Mike’s coarse grind was done on a file, so it is very coarse, but he’s since begun favoring very coarse stones over files.
The tests seem to indicate that you should think carefully about your grit strategy. If you know you have one particular usage that you do often, it’s worth a few minutes of your time to test out whether or not a dull-feeling 300-grit sharpened knife will outperform your razor-edged 1200-grit sharpened knife. The 300-grit knife may not shave hair well, but if you need it to cut rope, it may be just the ticket!
If you ever hear the suggestion that your knife may be “too sharp”, moving to a coarser grit is what is being suggested. A “too sharp” — or more accurately, “too finely polished” — edge may shave hair well, but not do your particular job well. Even with a coarse grit, your knife needs to be sharp, in the sense that the edge bevels need to meet consistently.”