About cleaning slip stones..

[graham-xrf]

This is about those AL/OX orange slip stones. "Medium" and "fine". It does not take much to have them clog up in a semi-shiny black stained something, even after only a few strokes. I think one can choose to use them dry, or with water, or with oil.

I am given to understand that once used with oil, you can't really go back to water, and probably not the other way either until the stone has dried out. I found that an ultrasound cleaner, with white spirit, was smelly choking, but it made a difference. Maybe stay with water + detergent plus a rub on diamond flat?

So what is the best way to treat slip-stones?

 

[pontiac428]

I think most people store their stones in kerosene. I can't see how that would be any different than mineral spirits in the sonicator.

Here's my honest answer- I use them until they turn black, then I use them as fine stones, and eventually I toss them because they come in boxes of 50.

 

[graham-xrf]

I think most people store their stones in kerosene. I can't see how that would be any different than mineral spirits in the sonicator.

Here's my honest answer- I use them until they turn black, then I use them as fine stones, and eventually I toss them because they come in boxes of 50.

Really? I think you must have a sweet bulk deal!
A 320 grit Kennedy stone 100mm x 25mm x 11mm slope to 5mm, from eBay here, is £11.99 (USD $15.23)

 

[Ianagos]

I have 2 stones for general purpose stoning and I just spray some wd40 and rub them together once they get a bit clogged up. They clean right up. Any embedded metal becomes a pain though.

 

[Tozguy]

I use cutting oil on mine. Once they start getting black streaks I dab some ISO 32 oil on them and rub with a finger. Hydraulic suction from rubbing seems to pull the fouling off the stone and suspend it in the oil. Then wipe off the dirty oil with a cloth or paper towel. As soon as the stone gets loaded I clean it. I would not continue using a stone that is loaded (black). It might make for frequent cleaning but that means its working.

 

[whitmore]

This is about those AL/OX orange slip stones. "Medium" and "fine". It does not take much to have them clog up in a semi-shiny black stained something...

Chemically speaking the 'shiny' is probably oils, and the 'black' is iron oxide (magnetite, hematite, etc.).
An ultrasound cleaner with water/(soluble-oil-or-waterless-handcleaner) mixture will both scrub (the water
does that) and float away the oily bits (the lipids in the milky stuff does that). A plastic tub with some oxalic acid
(warning: this stuff EATS iron, don't keep it near good tools) would presumably remove the black (it
will also remove blueing), but you'd want to be sure to remove all the residue.

For a quick touchup, a good plastic eraser (I like Staedtler-Mars plastic) will do a fairly good gummy-stuff removal,
and loose grit as well.

I suspect a solvent in an ultrasound bath is sub-productive (the ultrasound scrub action depends on WATER).

 

[Mitch Alsup]

Why would anyone ever use stones without oil on them ?

 

[Bob Korves]

I use kerosene, mineral spirits, or WD-40, whichever light solvent that is closest at hand. The solvent should be used liberally so the swarf can float away from the stone, and lifting the stone at short intervals so the gunk can escape easily from between the work and the stone. It keeps the stone from loading up, which essentially ruins it. Use enough solvent and the stone can be used on and on until there isn't enough left to hold onto, at least with ferrous metals.

 

[Ianagos]

Why would anyone ever use stones without oil on them ?

I use my stones dry a lot. Typically I’m just hitting a flat surface to check for burrs. I only add some wd40 and or mineral spirits when I have to do some heavy stoning which is pretty rare.

 

[graham-xrf]

Thanks to all for the replies, and the tips.

Before I came across HM, I used to think of stones as cutting tools, in the same sense as sharpening chisels on orange India, or getting that final edge on a blade from fine white Arkansas. The notion of a stone flat enough that the pressure is distributed so that the stone has no "bite" except on burrs and micron sized irregularities sticking up, did not occur to me. When I first tried it on a 123 block, and saw it reveal a surface grinder pattern, I was amazed that a (careful) stoning does not hurt the surface in any way important to dimensions.

Of course, I am not into $400/pair precision ground stones, and if my little engineering adventures ever called for it, I would hope to have my own surface grinder with diamond wheel as well. For me, I completely go for the @Bob Korves philosopy in post #8.