Ohishi waterstones

[Mike Brady]

Perhaps someone here can suggest a reason for a problem I have with two Ohishi waterstones. I am careful to follow seller's guidelines for use of sharpening media. I have 6000 and 10000 grit stones that have minimal wear on them. They have been stored dry in plastic boxes. I splash them with water before use, although the stones' surface almost immediately becomes "dry". I notice that they gouge very easily during chisel sharpening; and quickly go out of flat, particularly the 10000 stone. I suspect that the (clay?) binder that holds the abrasive particles has degraded to a point that the stones are essentially useless. I have other water stones and oil stones that perform perfectly well, and a new Shapton glass stone that is amazing in performance.

[Jimmy Harris]

You're probably pushing down to hard and using them too much. 6,000 and 10,000 grit stones aren't really for sharpening, they're for polishing. That's too fine of a grit to start on. It'll take forever to sharpen a chisel with that grit of stone, and you'll probably wind up pushing down too hard to compensate, or using them for too long. You want something closer to 800-1,500 grit for sharpening. And then maybe as low as 200-400 for grinding, should you chip your blade's edge (or use a grinding wheel). And it would be wise to get a 3,000ish grit to speed up the sharpening process and preserve some of the life of your 6,000 grit stone. Typically, you want to double the grit, or there abouts, when you move up to the next stone.

I rarely go above 3,000 grit these days. After 3,000, I usually move on to the strop and call it good. And I can get an edge sharp enough to shave with.

[Jim Koepke]

I splash them with water before use, although the stones' surface almost immediately becomes "dry". I notice that they gouge very easily during chisel sharpening

If they become dry almost immediately, they may need more water.

Maybe consider soaking them for a minute or more before running a chisel over them.

I occasionally gouge a stone. Most often it is caused by excess enthusiasm or lack of attention.

I agree with Jimmy that you may want to start with a coarser stone. My waterstones are usually 2000, 4000 & 8000 grit. If the edge is just starting to get dull often it can be touched up with just the 4K & 8K stones.

jtk

[Matt Riegerix]

My experience with the Ohishi stones I purchased from Lie Nielsen, a 1000, 4000 and 8000 is that they are not true splash and go stones. They need a bit of soaking, they also do gouge easily if you are not careful.

[Tom Bender]

Well said Jimmy