Thread: Waterstone - to soak or not to soak

For the mildew, put a few drops of White King in the water.

They say not to keep the stones soaked for too long but how long is too long.

I have a 6000/1000, 1200, 800, 200 and various slip stones. Mine have been soaked since the early 80s, minus the time it took to ship them here. They work just the same as they always did when new. In Canada re-wetting stones over and over hundreds of times isn't a problem, at least not on the west (wet) coast where dissolved minerals are very low. But here the dissolved mineral content in water (at least on the sunny coast) is very high as is evident by the amount of mineral deposits I've picked out of the faucet aerator. Multiple wettings will only deposit ever increasing amounts of hard undesirable minerals in the stones. At least that's my theory, YMMV. If they've changed the bonding agent for stones in the last 20 or so years then maybe there's something to it.

I use the water from a dehumidifier for wetting any kind of stone. I do not store in water, though I use Shapton most days now. But, I keep a Norton 4000/8000 in the kitchen for my Japanese cooking knives. Bleach in small amounts is a cure for the mold/algae and the like. There are waterstones that will get fragile from constant storage in water, but Kings are not among them. Usually it is a problen for the very cheap no-name stones. It has to do with the quality of the binders.mt

Initially I soaked my 6000 King in water, but you'll find you get better results if you use it almost dry for polishing. My recommendation would be to consider buying a King 1200 which you can leave soaking so that the 6000 can stay dry.

On the other hand, if you're comfortable with your process, the bleach idea also works.

Mine are soaked in water full time - I did this as I was pretty sure the instructions said to. I clean the water out every 6 months or so.

Here is the info from the the Lee Valley website:

Japanese water stones are quite porous and are designed for use with water as a lubricant and flushing agent. In general, water stones should be filled with water (it takes about 5 minutes immersion) and then kept in a bucket of water or a plastic container so that they are ready for use at all times.

There are two exceptions to this practice. Natural water stones are not kept in water and the finer man-made water stones (6000x and 8000x) on wooden bases don’t have to be. They can be wetted a few minutes before use, and will function well.

When sharpening with a water stone, keep the surface well wetted. The water flushes away the swarf and keeps new, sharp particles exposed for good abrasion. Just before you are ready to change stones (e.g., from a 1200x to 6000x), let the slurry build up and reduce the pressure on the tool. This slows the abrasion rate because the build-up contains smaller, broken abrasive particles and the reduced pressure further reduces the depth of abrasion. When you switch to the finer stone, you will achieve the desired finish faster.

Once again, as you approach the end of the process on the second stone, reduce the pressure and allow a slight build-up of slurry. The resultant edge will be better.

Japanese water stones tend to wear faster than oil stones – in fact, this is the secret of their rapid cutting rate. Be sure to keep your stone flat. To promote even wear, use the full surface of the stone and occasionally change the stone end for end. To true a water stone, several methods are available. A fine stone can be trued by rubbing it against a coarser one. The coarser stone should first be trued on wet-dry sandpaper laid on any true surface such as a piece of plate glass or a machined bed. 220x wet-dry paper works well.

To hold your stones in position when using them, a simple wooden jig that can be clamped in a vise or bridged across a sink or laundry tub is useful. Alternatively, a piece of rubber floor runner draped over the end of a workbench works well.

Caution: Do not allow your water stones to freeze when they are wet. They will fracture.

Cheers,

Tom