Ways to chemically dissolve waterstones to a pulp?

[Cottonwood]

As I have mentioned earlier, I ground up an worn out jap waterstone to make what has turned out to be an excellent stropping compound (on leather).
I was wondering, if there any chemistry type people who understnad these things, is there a way to dissolve old waterstones rather than grind them in a mortar an pestal (which took quite a while even with a soft piece of stone) As I understand it the man made stones are heated like pottery, is there a way to reverse that so you end up with an amount of sludge or slurry?
cheers Jonathan

 

[Kalimna]

Not sure if it would work, but have you tried completely soaking the stone, then place in freezer till well frozen?
The ice formation should induce microfractures and, at least, help to break it up.
This is one reason why stones should not be left soaking in a cold place liable to drop below zero.

Cheers,
Adam

 

[KevM]

Not sure if it would work, but have you tried completely soaking the stone, then place in freezer till well frozen?
The ice formation should induce microfractures and, at least, help to break it up.
This is one reason why stones should not be left soaking in a cold place liable to drop below zero.

Cheers,
Adam

This sounds like a good, safe, approach to try which avoids introducing unnecessary chemicals into your sharpening slurry. Natural freeze/thaw cycles are pretty effective at weathering our local Ham stone (limestone), as evidenced by the deposits of yellow sand on the pavements. The greater the temperature gradient, the stronger the effect will be. So maybe soak, deep freeze, warm - I'd guess you'd want to do all this in a polythene bag so that you don't lose too much of the stone/get too much grit in with your G&Ts.

 

[Cheshirechappie]

I'm talking from a position of supreme ignorance of waterstone chemistry, but my understanding of artificial abrasives is that they consist of two main ingredients. Firstly, sharp-edged hard particles of abrasive carefully graded for size, and secondly, a 'binder' to hold them in a sort of solid matrix. I gather that there are various binders, clay-based and varieties of ceramics being two sorts.

Finding a chemical that dissolves the binder material without attacking the abrasive material may be tricky. Most binders are fairly chemically inert, I think, so any chemical capable of dissolving it would have to be either pretty strong, or left for a long time to work effectively. I'm not sure I'd want strong chemicals such as concentrated acids in the workshop.

Maybe try a bit of crushed waterstone in vinegar. The crushing will increase the surface area available to the acid and speed it's action, and whilst it's fairly strong on the acid scale it's not dangerously so. You could neutralise the resulting mush by adding a bit of bicarbonate of soda.

All in all, I can't help thinking that just buying a small pot of silicon carbide powder of the grade you want would be much less hassle.

 

[Cottonwood]

All in all, I can't help thinking that just buying a small pot of silicon carbide powder of the grade you want would be much less hassle.

I'd get chromium oxide or rouge-I have a bunch of jap stone pieces and bits, its either get some use out of them or bin them.... :lol:
What I have tried so far makes an unbelivable stropping compound (and I've used quite a few different sorts). It isnt tacky or draggy, is drier holds up well and lasts longer, but it could definately improve even more with a finer slurry. the mortar and pestal works but there is still one or 2 odd lumps in among it. The 800 grit stone was quite tough, but the 2000 was easier to grind down

Doh, WHY didnt I think of the freezing option? (hammer)
After all the potters season clay by letting it weather and freeze, and bricks gradually spall and fall apart after being soaked and frozen....
I'll give it a try any way. Thanks for the sudgestions

 

[KevM]

Keep banging the rocks together!