Thread: Shapton Lapping Question

Hey all,

So I'm getting the full set (500, 1000, 2000, 4000, 8000, and 16000) of Shapton stones on glass and the idea of lapping them to perfection is driving me crazy. So my question is, would 15 micron (approximately 1000 grit apparently) be too fine to lap the Shaptons with? I have a local hardware store that sells a granite surface plate: Granite Surface Plate - Lee Valley Tools for a decent price, and it's flat to 0.0001" (about 2.5 mircon, a little flatter than the DGLP, ok, BARELY ). I was thinking of using it with this: 3M Micro-Abrasives for Sharpening - Lee Valley Tools, the 3M micro-abrasive sheets.

I like the idea of getting an exceedingly flat granite surface plate since it's a known extremely flat surface, but also because I can use it as a lapping surface AND for a honing surface if I decide to try honing with micro-abrasives. It'll be a LOT cheaper than a DGLP, and I can use it with multiple grits and uses.

Anyways, let me know what you think. I'm going to go pick it up now anyways, I just wondered if anyone has any feedback on it. Thanks!

P.S. Please don't suggest a DMT D8C for lapping, since I already have one. I know i'm being OCD about this, but that's ok, it keeps me busy.

Allow me to piggy back on that question about the granite plate
cause I'm on my second glass plate already.
Will it dish from using it with lapping powders?

Originally Posted by 0livia

Allow me to piggy back on that question about the granite plate
cause I'm on my second glass plate already.
Will it dish from using it with lapping powders?

Good question, I don't plan on using it with any powders, just as a backing for sandpaper/micro-abrassives. So I should never encounter dishing. Granite's pretty hard, so even with lapping powders I can't see it dishing for a long time...but have no experience with that.

Dave: 1k or equivalent lapping film would be fine to use on the Shapton glass stones to refresh the surfaces of the stones periodically. I have quite a range of the 3M lapping films and I have a granite surface plate from Woodcraft.

However.........you'll need to use your D8C to lap the Shaptons initially. Like any stone, they're not as flat as I'm thinking you're going to want them to be and if you were to start lapping using the 1k film on your granite plate outright, given the hardness of the ceramic, you'd.......be......lapping...a......LOOOOOONNNNGG GG.....time even to do a little work. Remember, you've got more than one plate to lap. Even with pre-lapping on the D8C, my guess is that this initial process with the way you'd like to carry it out is going to take you some time. I like where you're headed with this since I think stopping at the D8C on glass stones 4k on up leaves for a surface that's not smooth enough for me. The grit of each glass stone is the grit of each glass stone though, so even with a "rough" surface of a D8C on a 16k, you still have a 16k stone if you follow me.

I've used the DMT D8E to finish lap and refresh my Shaptons. The stiction makes for a problem that might also plague you with the film.

Chris L

Well I just got it. This thing is HEAVY!! Who would've thought a 9"x12"x2" piece of solid granite would be so heavy.

One side has a smooth surface while the other has a rough texture. Am I right to assume that the smooth surface is the one to use?

Yes, the smooth surface has been "surfaced". You're good to go. And, they are heavy.

Chris L

Originally Posted by StraightRazorDave

Well I just got it. This thing is HEAVY!! Who would've thought a 9"x12"x2" piece of solid granite would be so heavy.

One side has a smooth surface while the other has a rough texture. Am I right to assume that the smooth surface is the one to use?

Stone weighs on average about 170 lbs/cu. ft. So heavy it is. At least it doesn't move around much when you lean on it.

Yup, smooth side up