Sharpening with a 8000 grit stone?

Colinz · Sep 1, 2001

When I sharpen a knife I use:

A medium Arkansas stone.
A fine Spyderco ceramic triangle rod.
An extra fine (i believe, it´s black anyway) Arkansas stone.
An unknown brand of synthetic (ceramic?). It has a finer grit than the A stone. I use it for the final touch.

This setup has worked fine with knives I have had in the past, a soft Gerber LMF, An old SS Delica, A CS mini Outdoorsman. Nice edges on all of them. The problem is my Gunting (CPM 440V). It came with a sharp, but a little coarse edge. So I wanted to sharpen it to a mirror finish. I didn´t succeed even with my finest (unknown brand) rod. It looks better but I can still see some "scratches".

So now I am thinking of buying a "King" japanese waterstone in 8000 grit. I´ve read some about it being soft but are there anyone here that use (have used) a japanese waterstone(s)? Are they harder to use than a traditional Arkansas stone?

Thanks in advance for your help.

/Colinz

Roger Blake · Sep 1, 2001

Waterstones work great. You may not want to back to Arkensaw stones. They come in extra coarse to ultra fine grit like the one you mention. They cut faster than Arkensaw for the same finish. Their main down side is that they are soft and wear relatively quickly. Every so often they must be flatened. This can be done with silicon sandpaper on a flat surface such as a thick piece of glass or cast iron. A diamond stone also works well for flatening a waterstone.

If you are still seeing scratches I think you have to go to a coarser grit to get them out then move on to finer grits.

Crayola · Sep 1, 2001

Roger Blake pretty much hit the nail on the head. For natural stones, try out the water stones and back up on the grits first.

Most people on here that have the super CPM steels (including 440V) also purchase diamond and ceramic hones. Perhaps a Spyderco Ultra Fine ceramic home will do the trick for synthetic stuff.

bad4u · Sep 2, 2001

Take a look at the leather hones at www.handamerican.com.

These hones are offered with a variety of grits up 10000.

I set mine up with 600-grit for touch-up and 10000-grit for final polish.

Dark Nemesis · Sep 2, 2001

Originally posted by Roger Blake
Waterstones work great. You may not want to back to Arkensaw stones. They come in extra coarse to ultra fine grit like the one you mention. They cut faster than Arkensaw for the same finish. Their main down side is that they are soft and wear relatively quickly. Every so often they must be flatened. This can be done with silicon sandpaper on a flat surface such as a thick piece of glass or cast iron. A diamond stone also works well for flatening a waterstone.

If you are still seeing scratches I think you have to go to a coarser grit to get them out then move on to finer grits.

Roger:

With a normal amount of sharpening, say once or twice a week with different knives, how long do the stone normally last before they need to be flattened? Thanks

Colinz · Sep 2, 2001

Thanks for the input. I will buy the japanese waterstone next month.

/Colinz

Cliff Stamp · Sep 4, 2001

How much grinding you can do before lapping the hone depends on how much of the stone you are working on with each sharpening as well as how much work you are doing. The easiest way to figure out when they have to be flattened is to check them periodically. Take a pass on sandpaper on glass, if the hone is flat it will be abraded along the entire surface. If it doesn't then it needed to be lapped. You can also check them with a ruler, but if there are visible hollows present you are usually well past needing to be lapped.

-Cliff

Erikfsn · Sep 4, 2001

I used to use Japanese waterstones to sharpen my woodworking chisels. They did an excellent job on them; they cut very aggressively because they are soft and are thus constantly exposing new, sharp surfaces to the blade. I imagine they would work well on knives too.