[Christopher Kenji Gleeson]

In another thread, someone asked me how they could sharpen their KC bare blade. The KC is a katana blade, in 220 grit finish.

Here was my response, I think it might be useful in this thread, for those wishing to restore the cutting edge of their katana that are not nice enough to warrant a full polish. This is for 'working' blades only. If you try this with a Nihon-to, someone should smack you with a wet glove.

****

Never ever use a grinder, buffer, or any other buffing/sharpening device that generates heat on a blade that has been heat treated. This goes for katana and western blades as well. If you raise the steel's temp to 400-500 degrees, even just along the thin edge, you will ruin the hardening.

Here is what you should do, unless you want to try a full polish.

Your KC blade is only in 220 grit finish. It is probably already sharp enough to be an effective sword. Swords do NOT need to be the same kind of sharp as a knife, in fact it can be bad for them in certain cases.

Go get yourself 400, 600, and 800 grit sandpaper. Get the good 3M stuff, no cheap imitations. You can find them at any fiberglass supply, or autobody supply shop. They are not expensive.

Tear off postage sized pieces of the paper starting at 400, and with water, run them along the edge with your finger CAREFULLY. You will want to have the pressure at a 30 degree (or therabouts) angle to preserve the geometry already there. Run them down the edge in long strokes lengthwise down the blade. Make passes with 400 grit until you feel the edge smooth out (you will feel it if you pay close attention). One of those squares is only good for about 5 passes, so you will use a few. Repeat this all the way up to 800 grit, and your blade will be as sharp as the devil himself.

This is basically what I did when I was finishing the hybrid polish on my KC blade, I spent time at each grit trueing the edge in this manner, and by the time I got to 800 it was scary sharp.

The important thing, is that this way, you will not ruin the geometry already in place, you will just hone the edge to a fine surface.

BE CAREFUL, DO NOT CUT YOURSELF!!!

I can't stress this enough, you must pay attention, turn the TV and music off. Focus on what you are doing, or you can get cut.

With the 3M paper I never had it cut through the paper, partly because it is good paper, and mostly because my angle was correct with respect to the edge. You should be able to do this with a piece of newspaper and not cut through, if your pressure and angle are correct.

A consequence of this method, is that your edge will be nearly mirror shiny afterward. If you did this to the whole blade, you would be on your way to a beginner's hybrid polish like mine.

****

And a picture (or two) for reference.

Best.

Chris.