Shapton Pro Stones Questions

[David Wong]

On my plate, it is the edges that are usually low.

When lapping, I only allow about 1/4 of the stone to go off the edge of the plate. Three quarters of the stone is always on the plate.

[Jebediah Eckert]

Thanks for the tips, I will try them all. My freehand was abandoned for the jig awhile ago but I will check out the Sellers method and try again.

[Allan Speers]

I use an Atoma for flattening my stones, but FWIW, I know an old timer who uses a concrete block & a running water hose, and swears by it. Think about it: One surface of a block is dead-flat, because it's created by gravity. The benefit is that you have a very large surface to work with, so none of your stone is ever hanging off an edge. You thus have a better chance at getting an even surface.

I suppose an EZ sharp system with course sandpaper would do just as well, never tried it, though. - But how cool is using a concrete block?

[Jebediah Eckert]

Thanks Allan. Do you use the Atoma 400 as well for all your grits of stones?

[ian maybury]

+1 that a 400 or thereabouts diamond seems to do a very god job on everything Shapton down to 12,000 at least. Separately - wonder if uneven distribution of loose carborundum grit on a lapping plate has the potential to cause an out of flat stone?

As recently discussed at length it's hard to overemphasise the frequency and flatness bit, especially if working with a honing guide. Not all diamond plates are accurately flat, so test carefully before use with a precision straight edge against the light in all directions. Send it back if it's not perfect. They need to be flat within microns if you plan to reliably cut right to the edge and along it's full length on a very fine stone. There's probably a bit more tolerance possible if stropping - i'm not sure how people get by with concrete cap stones and the like but stuff like this seems likely to be in the mix.

Micro bevels and hand sharpening (where it's easier to cut right to the edge/it's possible to steepen the angle a hint if needed to get to it) must make it a bit less sensitive, but even at that a hint of widthwise out of flatness has the potential to mess things up.

Having scribbled all over the surface with a pencil flatten the stone - until all of the pencil marks are removed. Take care to apply even pressure/to not tilt the plate, and don't overdo the pressure. Rinse at intervals if it's taking a lot of cutting - large deposits of slurry have the potential to tilt the plate a hint or lead to uneven cutting and cause a problem.

Then hone for a bit in a movement that spreads the wear evenly over the stone and avoids hollowing (see David Charlesworth's 'A Guide to Hand Tools and Methods, p. 84 onwards for specifics - not more than 30 - 50 strokes in total, less on a narrow chisel where the wear will be faster), then flatten again. Repeat…. A ply handle stuck on with high strength (permanent) flexible double sided bonding tape works well on the Atoma (see previous pic posted), and doesn't risk warping the plate.

Done this way the blade will only work a given area of the stone at most several times at most between flattenings.

This may sound OTT, but believe me - it's necessary if you want to get consistently sharp edges off a waterstone with a honing guide. Especially so if honing single bevel as on Japanese chisels. Even very minor/invisible irregularities will mess it up - i used my first well worn Atoma to try to dress a Tormek stone, and even though it looked fine it started as a result of uneven wear to act up by virtue of slow cutting/an invisibly lowered surface in some areas. Close inspection showed that my Japanese chisels were not quite cleaning up uniformly all over the area of the bevel (sometimes leaving a hint of wire edge behind) as a result of some combination of the diamond plate having caused microscopically out of flat stones, and/or the bevel not being quite flat from the previous stone. A new diamond plate instantly resolved the problem.

It's soooo easy to get into a mode of sharpening where we go though the motions without actually SEEING what's going on at the edge (sharpening by numbers), and this is when inevitably some variation creeps in and causes a problem...

[Jebediah Eckert]

Well......after getting fed up with the Shapton lapping plate I ordered the Atoma 400. I figured the Shapton plate just wasn't flat enough to get good results. The Atoma came today in the mail, I opened it, and started round 2 of flattening.

They are "flatter" for sure, but I say an ever so slight ray of light from dead flat. I stopped because there was no way they were getting flat, I was at it awhile. I altered patterns, very very light pressure, just enough to get it moving. I went from 8000 to 5000 to 1500 and cleaned the plate spotless between grits with several rinsing during the process. I did two and even 3 rounds on each stone with the pencils marks until they were all gone. The Shapton stone was in the lapping plate holder and I worked the Atoma on top only letting the Atoma come off the edges 10% or so tops. I went slow and very diliberate with very light pressure.

Again, they are "flatter" then before but all 3 stones are scratched prett badly. I'm not sure how well it will show up in the picture. A bunch of people suggested this method so I can't be the only one experience this?

Any ideas?

image.jpg

This was the last stone it did (1500) and took the picture after a few strokes. The other stones have scratches are all over the place from altering the pattern.

[Paul McGaha]

Well......after getting fed up with the Shapton lapping plate I ordered the Atoma 400. I figured the Shapton plate just wasn't flat enough to get good results. The Atoma came today in the mail, I opened it, and started round 2 of flattening.

They are "flatter" for sure, but I say an ever so slight ray of light from dead flat. I stopped because there was no way they were getting flat, I was at it awhile. I altered patterns, very very light pressure, just enough to get it moving. I went from 8000 to 5000 to 1500 and cleaned the plate spotless between grits with several rinsing during the process. I did two and even 3 rounds on each stone with the pencils marks until they were all gone. The Shapton stone was in the lapping plate holder and I worked the Atoma on top only letting the Atoma come off the edges 10% or so tops. I went slow and very diliberate with very light pressure.

Again, they are "flatter" then before but all 3 stones are scratched prett badly. I'm not sure how well it will show up in the picture. A bunch of people suggested this method so I can't be the only one experience this?

Any ideas?

image.jpg

This was the last stone it did (1500) and took the picture after a few strokes. The other stones have scratches are all over the place from altering the pattern.

I use an Atoma 400 on all my stones 1000 grit and up. It works great, easy, very light pressure, I keep the diamond plate stationary and move the stones just front and back (longways). It flattens them easily. At Stu's advice I've flattened Shapton Pro stones all the way down to 320 grit with an Atoma 400.

That looks to me to be way more course than a 400 grit Atoma. Waaaaaaaaaaaaaaayyyyyyyyyyy more. Maybe it was labeled wrong or maybe it's just defective. The Atoma 400 should do a wonderful job of flatening your shapton pro stones.

I suggest you get that picture to the vendor you bought the Atoma from and get it exchanged.

Good luck with it.

PHM

[Jebediah Eckert]

I will post a picture of the Atoma, maybe you can tell from that? The sticker on the package is correct but who knows.

The Atoma is dead flat, on the business side anyhow.

How bad are the scratches going to be for sharpening results?

[Paul McGaha]

Jebediah,

Maybe feel along the Atoma with your finger. Maybe you can find a burr on the plate. It could be a single burr doing all the damage.

Hopefully the scratches aren't too deep. It would be good to get them out.

[Allan Speers]

Thanks Allan. Do you use the Atoma 400 as well for all your grits of stones?

Yes.

It really doesn't matter how fine the stone is, because it's still seeing a flat diamond surface.

BTW, I started using the Atoma on the advice of Derek Cohen.

[Jebediah Eckert]

I doubt you can tell from the picture but here it is. I'm not sure if the different grits are patterned different, or color, or anything like that.

Also I felt the surface and I haven't been able to feel a burr or any kind.

image.jpg



I'm not sure why I am having such poor results with it. I ended up redoing the Shapton stones on sandpaper on a granite plate. I got a good portion of the scratches off but it took a looooong time. I probably should have saved the $75 and flattened them like that to begin with. It just seemed like I was always out of the sandpaper I needed when the time came, plus I was hoping for an easier way. Somebody above said life was too short for poor sharpening system, agreed. However, the pursuit of improving my sharpening (flattening my stones) is slowing driving me mad.

[Al Launier]

By no means am I skilled at sharpening, but I use a 12" x 18" piece of plate glass with wet/dry paper to sharpen my tools. I think people can get "over zealous" with sharpening.

[Paul McGaha]

Jebediah,

I'm sorry you're having trouble.

If you're sure the scratches came from the Atoma 400, I really do think it is defective and should be replaced.

I have Shapton Pro Stones in 320, 1K, 2K, 5K, 8K, and 12K grits. I routinely flatten them with an Atoma 400 with the exception of the 320 which I usually use an Atoma 140 (Although the Atoma 400 will flatten the 320 too).

I'm glad the scratches are coming out without too much trouble.

PHM

EDIT - I'd add that I think a diamond plate like an Atoma 400 really is a very effective means to flatten water stones. It's the best method that I've found. Fast (Draw a grid pattern and flatten in less than a minute I would think), Less of a mess than wet sandpaper, Affordable.

[Jebediah Eckert]

Thanks for the help Paul. I may try it on one of the stones again. Under the theory there may have been a burr and when I got down to the 1500 stone it knocked it off. If it still gouges I thinking sending it back is the call.

[Brian Holcombe]

It's possible a stray grit was in the stone or the plate. I've had that happen....in my case on a finish stone . I'm now very careful about stray grits. Everything stays separate.

i've been advised of 1200 atoma plate for lapping finish stones and so...eventually I will have that myself along with a 400 to replace my DMT. I think my DMT is a 325, and I very much dislike it. I have an old serrated top DMT that I like but it's not accurate in flatness.

Accurately flat stones do make life much easier on the finish stone, because the more accurate your work up until then the less work you will need to do on your finish stones.