Thread: Sealing synthetic waterstones

Molds need oxygen and if it is sealed it won't mold. At least on the inside of the seal........

you know this hasn't shown that sealing helps or is bad, so far. so its totally a user choice, either or it wont make a difference. so if it makes you feel better seal it! those who don't will still have a flat stone as a guy who seals. there is only one way to tell, you need to purchase 2 full sets of naniwas, seal one and not he other, put them in a time capsule and open them up in 100 years,

I,m not sure of mold, but Tim it wont be sealed on all 6 sides, so yes mold can grow. Tc

That 2nd pristine, unused $300 10k, sitting in that time capsule, even after the near-consensus online that even one is overpriced for what it is -- that's when you know that moreso than you having HAD...
The HAD has you.

There are a number of ways to cause crazing & cracking on non clay based stones. Rapid drying is the biggest one.
Air con ,fans & bright sunlight come to mind. Excess soaking,hot water, soaps, detergents, washing soda can all soften them.
Nowhere on any instructions have I seen a recommendation to seal them but sealed or not, the above conditions would still damage the stone.

The only synthetic that crazed on me was a 12k Shapton Ha no Kuromaku which was left on a sunny bench & dried too fast.

Originally Posted by holli4pirating

I would worry about sealing 5 sides, because water that penetrates into the bottom of the stone would have no easy way out. Then again, maybe that would cause a slower and more even drying process... It will also be interesting to see what it's like honing on top of a pool of water... It will be an interesting experiment.

So, a few months later and a few pounds heavier...

I finally felt the need to hone a razor on the permasoaked King Deluxe 1k I sealed in spar urethane last year -- I've used it a few times on knives and sundry things since then, but no razors until today; and I figured I might as well report back with some thoughts:

I'm finding the properties of the sealed King pretty great, actually: It doesn't dry out at all, that means no needing to add more water which sometimes spills over the sides if I add too much, whilst also diluting the slurry even if I'd rather keep it as is.

In fact, slurry is why I felt like grabbing the King today -- I wanted something which would muddy more than the Chosera 800 I was working with, even with the very light pressure I'm using on a supple full hollow grind. The King fit the bill nicely and this way the slurry doesn't dry into thick mud too quickly, or at all in fact, which is how I like it for a razor.

Not drying out on account of the stone being waterlogged and the sealant preventing water egress from the 5 sealed sides also means that for once there isn't a puddle forming under the King. Another nice win.

On the other hand, if someone is in the habit of using the stone's drying out to their advantage, perhaps because they've intergrated the progressively dryer mud into the way they use the stone, they could be frustrated by how wet the surface stays virtually indefinitely -- although I don't find working the mud on a 1k King in this fashion to be useful for razors. Regardless, the slurry's remaining completely wet and not drying to a thicker mud does hamper the stone's tendency to impart a dark hazy finish, based on the few knives and chisels I've experimented with.

Those are the more pertinent observations I can think of with regards to the actual usage of the sealed permasoaked King. That said, there are a few other little nuggets of dubious usefulness I've collected:

The thinner coats of urethane I used on the King 1k worked well compared to the Naniwa dressing stone; that and allowing for roughly double the curing time between coats resolved having parts of the sealant remain soft, absorb water and discolor when submerged for long periods.

Once submerged for a while, the surface texture of the urethane went from smooth to bumpy -- I think it must be tiny bubbles trapped by brushing, which expand with water. I left the stone to dry out once -- it does take much longer to dry out completely now -- and the surface regained it's smoothness. So -- and not that it matters -- but if I did seal Choseras in a similar fashion I do not think their coating would feel rough like the soaked King's, on account of much shorter exposure to water.

All told, the sealant has been underwater since shortly after my last post here, and it's held up fine. I am however careful not to let the coated surfaces rub or knock against other stones because I doubt that it would take much to lose the watertightness.

Also, the sealant layer has a tendency to stick around even as the stone is worn down beneath it from usage. Hence I have to take care to cut/grind the extra sealant at the edge where the top meets the sides as part of maintaining/flattening the stone, otherwise pieces of sealant flake off. Because of this, I've slightly tweaked my usual way of chamfering the edges with a diamond plate to be more deliberate way than usual: making an effort to cut the layer without pealing it from the stone.

I must say that a more strongly bonded layer, epoxy for instance, presumably wouldn't have either of these last two issues. Cost notwithstanding...

Finally, looking back on this thread I remembered that mould had been brought up as a concern -- although I believe that it must have been in reference to my plan of eventually sealing Choseras rather than the the intermediary step of the permasoaked King stone; because Choseras must be dried between uses, almost by definition; at which time mould could become an issue, I'm assuming -- In any case, Sealing the King hasn't changed anything with regards to mould: a cap full of bleach every few weeks, when I change the water in its happy little bucket aquarium, has worked very nicely so far.

One of these days, I'll finally get around to sealing my Snow White like I've been meaning to.