Stone lapping query

[Raymondmillbrae]

Ok, quick question.

I am considering purchasing a small 8oz bottle of Silicon Carbide to do my stone lapping. (Sprinkle a bit on glass, add some water, “Wa-La”).

And since I am now going to practice setting a bevel, I jumped on a Shapton 5k stone as well.

Is the 400f Silicon Carbide enough to flatten the stones when they arrive, and maintain them as well? Or should I get a courser grit?

How about a 180/220f size?

I was also considering film. But the silicon carbide will be cheaper, and last longer.

What do you say?

I was looking around for a 120f size but couldn’t find any. Anyone know of a place that sells silicon carbide in the 120f size by chance? (A link would be nice).

 

[bluesman 7]

The 180/220 size should work OK for flattening, though I usually use coarser for heavy flattening. For just light lapping and maintaining stones 320 grit W/D works very well and is cheap as chips as it lasts quite a while.

 

[Raymondmillbrae]

So the silicon carbide in 180/220f and 400f should be all I need to lap my new stones when they arrive, and also maintain them, right?

 

[Sinnbad11]

Yes 180/220 can do any major flattening work and 400, especially after breaking down to finer grit, is a fine working surface for stones.

 

[bluesman 7]

I would still recommend the W/D over loose grit, partly because it is less mess, and don't forget that as you flatten your stones on grit and glass, you will also be dishing the glass.

Do as you wish though, grit and glass is cheap and useful to have around, and you won't harm the stones. You can try a piece of W/D on the other side of the glass whenever you want. Not much ventured either way.

Edit;I would add that certain stones (Crystolon) react very badly to W/D and do great with loose SiC, but water stones all do well with either AFAIK.

 

[Raymondmillbrae]

I would still recommend the W/D over loose grit, partly because it is less mess, and don't forget that as you flatten your stones on grit and glass, you will also be dishing the glass.

Do as you wish though, grit and glass is cheap and useful to have around, and you won't harm the stones. You can try a piece of W/D on the other side of the glass whenever you want. Not much ventured either way.

Ive actually been thinking about that exactly. (The glass being “dished”).

If I were to use w/d film, how is it held onto the glass or granite so it doesn’t slide around during the lapping process?

And also, I’ve read that folks use paper between the film and glass. Once again, how do you do this without is sliding around during the lapping process?

Or does the “suction” hold it in place?

 

[bluesman 7]

I think that you're confusing people using lapping film for honing razors and Wet/Dry sandpaper for flattening stones.

I usually glue down the W/D with spray contact cement. Just water will hold it down enough for a quick eval. Some people tape the edges down if you've got the real estate.

Paper under lapping film is used at the very finish of honing a razor to microscopically convex the edge. Lapping film is held down with just water tension, but again film is used for honing razors and would be overkill IMO for lapping stones.

 

[Raymondmillbrae]

I think that you're confusing people using lapping film for honing razors and Wet/Dry sandpaper for flattening stones.

I usually glue down the W/D with spray contact cement. Just water will hold it down enough for a quick eval. Some people tape the edges down if you've got the real estate.

Paper under lapping film is used at the very finish of honing a razor to microscopically convex the edge. Lapping film is held down with just water tension, but again film is used for honing razors and would be overkill IMO for lapping stones.

Perfect, thanks.

I recently purchased a Naniwa (S2) 8k and 12k Super Stone.

And then I purchased a Shapton 5k as well.

All are in transit for delivery.

If I were to go with w/d sanding paper (120 grit, and 400 grit), what would be a good size?

I see packs of 25 sheets at 5.5”x9” inches.

Too small, or will they do?

Or should I go with 10 sheets of 9”x11” inches?

I’ve never lapped a stone before, so I don’t know if the sandpaper will move around or not.

Thanks.

 

[rbscebu]

I use 9" x 11" W&D on glass to lap me whetstones. I find that I don't need to attach my W&D to the glass for lapping. By using the W&D with water, the water tension and finger pressure is enough to hold the W&D in place.

 

[bluesman 7]

I use a partial sheet at 3½" X 11", but that's because my piece of marble tile was that size. I use 320 grit only. The Naniwa Superstones are very soft, so the grit does not mater very much as the stone surface cuts easily and returns to its natural texture quickly. I glue my W/D down out of convenience. One application of W/D lasts long enough that having it glued to the tile is an easy way to store that piece of sandpaper. I have to store the tile someplace anyway. If you're in the U.S. you can buy 320 grit W/D at home depot or most hardware or auto parts stores in 4 packs, or even single sheets at some hardware stores.

Whatever you choose to do will work fine.

 

[Raymondmillbrae]

How does everyone “glue down” their w/d sandpaper?

Specifically - what type of glue, how much glue, and where do you place the glue on the w/d paper?

 

[Sinnbad11]

3m spray adhesive works well.

 

[Raymondmillbrae]

3m spray adhesive works well.

Must be a nightmare taking it off.

Or does a razor scrape it off easily?

 

[Sinnbad11]

Must be a nightmare taking it off.

Or does a razor scrape it off easily?

A razor and goo be gone/acetone seems to do quite nicely, but it can take some work.

 

[life2short1971]

I would lean towards a diamond plate if even just a cheap one because they are so much more convenient. I use SiC myself for lapping very hard stones when I first receive them but use a 600 Atoma for all else. SiC powder will inevitably get lodged on the stone you lap or just end up there from your clothes or some other way leaving big nicks and deep scratches in the bevel of your favor razor when you least expect it and its also messy as hell and best used outside weather permitting and definitely away from your honing station.

 

[life2short1971]

How does everyone “glue down” their w/d sandpaper?

Specifically - what type of glue, how much glue, and where do you place the glue on the w/d paper?

Wet dry paper will stick to your glass, tile, or marble plate with capillary action after you wet the surface and lay the paper down. There is no ned to glue the paper down and as fast as you'll go through sheets I advise against gluing it down if you're determined to use wet/dry paper.

 

[David]

Wet dry paper will stick to your glass, tile, or marble plate with capillary action after you wet the surface and lay the paper down. There is no ned to glue the paper down and as fast as you'll go through sheets I advise against gluing it down if you're determined to use wet/dry paper.

It always curls up on me when it gets wet. Maybe I’m doing something wrong?

 

[life2short1971]

Maybe low grade paper or your using it too long? You do know the the side with the writing goes face down??
Its actually telling you to quit being such a cheapskate and buy a new lapping plate David.

 

[David]

Maybe low grade paper or your using it too long? You do know the the side with the writing goes face down??
Its actually telling you to quit being such a cheapskate and buy a new lapping plate David.

Crap. Well that explains why I go through a granite slab a month at least!

 

[life2short1971]

Crap. Well that explains why I go through a granite slab a month at least!