Flattening a Fine India

[David Barnett]

My pleasure, Steve.

[Russell Cook]

Hi all,

I've got the stone flat now, using SiC grits 36-60 on glass.

However, some of the gunk that came off the fine side got into the pores on the coarse side.

I washed it in soapy water and rubbed the coarse side with my hand, quite a few times. It got a lot better, and it cuts OK still, but some patches are still not totally clear.*

What could I do to clear the pores out a little more? Dishwashing detergent with a toothbrush? Vinegar and toothbrush? Please don't say boil it!

[David Weaver]

boil it....oops. Not sure what to suggest. If you use the stone often, you'll end up using it somewhere between it's coarsest cutting and no cutting at all, because it will consistently stay at an in between level, but keeping it cutting as fast as it did as perfectly new is a pretty labor intensive endeavor.

[Russell Cook]

Cheers for the reply, David.

Well, I used it this morning to prepare a new chisel for use (my set of chisels did not come ready to use!) and it worked well, so I'll think I'll stick with it as is for now.

I have the vague idea of once every year or two boiling all the oil out, re-facing both faces, and then refilling it with oil.
I found lapping it with oil still inside to be a bit of a pain.

[David Weaver]

If you use a very liberal amount of oil on the surface of it once in a while (and hone while it's like that) it should stay in good shape indefinitely and be very useful, even if it doesn't cut as fast as they do when they're freshly agitated. That fresh speed is too fast cutting for me, it wastes off too much steel.

I have a little bit of a problem with stones of just about any type (as in I buy them when I don't need them) and to a T, when I get a group of stones and a bunch of india stones come with them, they look like they have been very lightly used and then discarded once they're loaded. There must be machinists (or must have been) who used those common stones until they were loaded and then let the company buy a new fresh one.

[Steve Voigt]

That fresh speed is too fast cutting for me, it wastes off too much steel.

Yeah, me too. I'm a recent convert to India stones.I love the "fine" stone, but after hollow grinding, it only takes about 6 strokes to put a nasty huge burr on a blade. I've actually been thinking about getting a soft Arkansas and trying that for the first step off the grinder (btw, really like that black arkie you sold me).

I have a little bit of a problem with stones of just about any type (as in I buy them when I don't need them) and to a T, when I get a group of stones and a bunch of india stones come with them, they look like they have been very lightly used and then discarded once they're loaded. There must be machinists (or must have been) who used those common stones until they were loaded and then let the company buy a new fresh one.

I don't know if my experience is typical, but in my old machine shop we didn't use stones at all. We ground almost everything on Baldor dry grinders with grey wheels, then honed a secondary bevel with a fine diamond wheel.

[David Weaver]

I think you're probably correct, the india stones that I've gotten in bunches are hard and old, and experience with newer ones (that are a little more friable, especially the silicon carbide side on combination stones) and lots of old ones (that are bone hard all the way around) makes me think they were loaded up and discarded many many decades ago. I can imagine people would've used them on carbon steel and HSS cutters, but I can't imagine anyone would use them on carbide tooling, or even HSS once diamonds became relatively affordable.

Glad you're pleased with the stone. Norton's black stones are a bit different than the other brands I've tried. They have some tooth, but that may disappear in time. Some of the perceived toothiness of norton's fine stones probably has a lot to do with how they finish the surface of the stones, though, and I never did use that one enough to find out where it would end up. It's only probably a clinical disorder that's given me enough curiosity to buy and fiddle with all of this stuff, but I still love to try different stones no matter what they are.

[Russell Cook]

Cheers for all the info,.

Btw, I'm also quite fond of my India combo stone. My introduction to sharpening was Leonard Lee's book, in which oilstones in general are reviewed very unfavorably, but I've been happy with how it works.