Thread: Suehiro Gokumyo 20K

Originally Posted by JimmyHAD

Been thinking about this 1200 stripping diamonds on the 20k. Going by the unfortunate experience of Sham with his DMT 1200 (which Dia-Sharp did replace BTW) I was figuring that because of the different construction of the Atoma it was probably alright to lap waterstones.

I have found this to be the case & I lap harder stones than the 20k. In fact when I first met So & he suggested these plates to me, he had used his already for 7 or 8 years on his Jnats.

Dia-Sharp specifies (after the problem with Sham's) no higher grit than 325 and that under running water. Before Sham posted his warning I was using a DMT D8C 325 at home, and a DMT 1200 at work. I noticed that the Norton 4 had grey streaks on it when I lapped it with the 1200. Curious. Fortunately Sham posted his experience and I realized the grey was the diamond and substrate nickel stripping off of my plate. I say fortunately because I hadn't ruined the thing.

So...... cutting to the chase .......... if the 1200 isn't good for lapping the 20k, is it alright for other waterstones ? I realize the 20k is super hard. The next question ........ if the 1200 will strip diamonds on the 20k, what plate won't ?
As above.
Maybe I'm stuck with the loose grit on a ceramic tile ? If I had it to do over I'd just stick with the Naniwa Superstone and the hell with it.

Flattening stones of differing warp requires different tools. SiC on glass etc is easy & effective. For daily maintenance & slurry making I use the 1200 Atoma on all stones 8k & up.
Below that, ie 1k-5k I use my 400. For my 320 Pro I use a 140 Atoma. I would not use a 1200 Atoma on a 1k stone any more than setting a bevel on a razor with a 12k stone.
Horses for courses.

There is one stone that will destroy most diamond plates in short order & that is the Spyderco UF. 2 mins max with a 1200 Atoma will see it adequately "broke in" beyond that , well, its your plate .

I've looked at the 20k under magnification and it appears okay. Going by the aforementioned experience with the grey streaking on the DMT I note that I've seen none of that on the 20k. I've always lapped under running water, and always the tail end of the job. So maybe I've dodged the bullet. Examining the plate (magnification) the diamonds are consistent, and not badly worn.
I think that says it all.

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