Thread: Honing/lapping use a DMT325 or an Atoma 400

http://http://straightrazorpalace.com/workshop/72230-dmt-dia-sharp-dia-flat-plate-lapping-plate-10-x-4-a.html That very post would be found here Jimmy. I dig deep into the archives of SRP for information, you could say i'm on the hunt for knowledge.


I just figured out how to link other threads into current ones,

Originally Posted by S0LITARYS0LDIER

I'm going to go on a hunt for that post Does it really even matter what your hones are lapped to grit wise as long as they are flat and consistent?

It doesn't matter much on softer stones like Shaptons, Choseras, Norton water stones et al as long as the diamond plates in question are worn in a bit. Super hard natural stones like Arks are different - they need a very smooth surface to work at their best.

Brand new diamond plates will tear the hell out of a stone, and then it will leave a bit worse finish. Once they are worn in it literally barely makes any difference at all to the finish on the steel what grit diamond plate you use to lap the stone. I have done tests and can't really tell much if a difference from a DMT XXC or Atoma 140 and a DMT 325 or Atoma 400. The Atoma 1200 gives a slightly better finish but barely noticeable at 150x magnification. A brand spanking new diamond plate of any grit used to lap a stone gives a noticeably worse finish on the razor. I highly recommend breaking in the diamond plate a bit with a chisel, screwdriver or whatever before using it on finishing stones.

The significant difference between using these different lapping plates to flatten your stones is that they dramatically alter the cutting speed of the stone until it starts to shed some abrasive particles. Flattening with the coarser diamond plate results in faster cutting while the finer results in much slower cutting.

Originally Posted by eKretz

Brand new diamond plates will tear the hell out of a stone, and then it will leave a bit worse finish. Once they are worn in it literally barely makes any difference at all to the finish on the steel what grit diamond plate you use to lap the stone. I have done tests and can't really tell much if a difference from a DMT XXC or Atoma 140 and a DMT 325 or Atoma 400. The Atoma 1200 gives a slightly better finish but barely noticeable at 150x magnification. A brand spanking new diamond plate of any grit used to lap a stone gives a noticeably worse finish on the razor. I highly recommend breaking in the diamond plate a bit with a chisel, screwdriver or whatever before using it on finishing stones.

Thanks for the advice. I'm completely inexperienced with all this, but after reading so much about them, I recently got a brand new DMT D8C (325) to use on my equally new Naniwa 1K, 5K, 8K and 10K super stones. Any more tips on how to break in the DMT? All my stones are brand new as well, and now I'm reluctant to lap them and lose their silky smooth surfaces!

Originally Posted by wjosephsimmons

Thanks for the advice. I'm completely inexperienced with all this, but after reading so much about them, I recently got a brand new DMT D8C (325) to use on my equally new Naniwa 1K, 5K, 8K and 10K super stones. Any more tips on how to break in the DMT? All my stones are brand new as well, and now I'm reluctant to lap them and lose their silky smooth surfaces!

Like mentioned above a old long screwdriver will take care of breaking in the DMT. Just rub the shaft of the driver onto the DMT with decent pressure and it will start to break it in. As to your other stones, if you don't lap them that silky smooth surface will be useless if they are not flat at least to the standards that DMT uses on their Dia-Sharp plates. I have a shapton 16 and I thought the same especially since the Glass Stones are only 5mm thick but when I went to flatten them I noticed that it was no where near flat and would not have produced a good edge until I gave in and flattened/Lapped it. And every once in a while you will have to lap your stones again because pressure, humidity, and temp differences will slightly "warp" a stone. Not much but enough to pull from flat. I noticed this with my 16k where I flattened it; honed a razor; and then the next day the high spot was in the middle not on the edges as one would assume. That is why I give a quick 5 or so laps before each honing session. Happy Honing.

I have used a 300 Trend, 325 DMT and Atoma 400 on my 20K Suehiro. The Suehiro is a hard stone and I use pretty light pressure to mostly clean it under running water it vs. lapping. To me mostly flat is good. I have not found that any of the scratching from the plates interferes with the results from the Suehiro stone and mine gets use daily. At this moment, this stone may be the best finisher out there in my opinion as well as extremely consistent and reliable. YMMV.

How's that for clarity from the honemeister himself. Always a pleasure to read what you've got to say Lynn.

My initial question about lapping plates, and their 'breaking in'? Oz (Onimaru55) said the Atoma 400, would be broken in after Lapping just one hone. That being said, some have said that the DMT325 can be broken in with a screwdriver. So the conundrum is, Am I going to get better results in lapping/truing say a Suehiro 20k with one or the other. I think I may be a bit manic about having scratches on $300 hones. So gents, we agree, from Oz that the Atoma 400 requires very little breaking in, if you could even call it that. I have a DMT325 that I have IMO broken in. The question I'd like an answer to, is, if you are lapping high grit stones, up to 20k, that are hard, which is the better plate for lapping, is it personal preference or is there a typical reason for one over the other. (DMT325 or Atoma 400) I understand Lynn's view, with the number of razors/hones he goes through, but for amateurs who like to attain excellence, is there a better way? Thanks Bob

The only benefits the Atoma offers is:

1. Consistent flatness for their low cost.
2. A surface that doesn't stick easily to the stone you lap.
3. An easily replaced lapping surface when the time comes.

I usually use the 1200 on my 20k & Jnats. I have yet to find any problem from any scratches the plates leave.

I just bought a New 20K and a 1200 Atoma. Started with DMT325 old work horse, after 5 minutes of pain. Opened up the New Atoma and it lappped the 20K in 5 minutes.
Felt like winning the lottery getting both tools at once.

Originally Posted by ultrasoundguy2003

I just bought a New 20K and a 1200 Atoma. Started with DMT325 old work horse, after 5 minutes of pain. Opened up the New Atoma and it lappped the 20K in 5 minutes.
Felt like winning the lottery getting both tools at once.

I've heard that the Atomas leave the DMT 325 in the dust. Really getting the urge to pick one up come payday!