Thread: Suehiro Gokumyo 20K

Originally Posted by mainaman

400 atoma, when new, will take care of the Suehiro, easy.

The one I received was shaped like a banana so I started with 80 grit SiC on float glass. Then progressed thru 140, 400, 1200 Atoma.

I lapped the concave side as the 2 ends gave me starting points. The convex side would have been impossible

The key with not embedding particles into a stone is just use the weight of the stone when lapping.

Soft stones like Nortons are more prone to getting grit stuck to them. The 20k is so hard it would take some ham fisted pressure to embed anything into it.

Originally Posted by onimaru55

The one I received was shaped like a banana so I started with 80 grit SiC on float glass. Then progressed thru 140, 400, 1200 Atoma.

I lapped the concave side as the 2 ends gave me starting points. The convex side would have been impossible

The key with not embedding particles into a stone is just use the weight of the stone when lapping.

Soft stones like Nortons are more prone to getting grit stuck to them. The 20k is so hard it would take some ham fisted pressure to embed anything into it.

Mine was within visual tolerance. it laps very easy with my new Atoma 400, it was hard to do much with my well worn DMT 320, or my old Atoma 140.

Originally Posted by mainaman

Mine was within visual tolerance. it laps very easy with my new Atoma 400, it was hard to do much with my well worn DMT 320, or my old Atoma 140.

Yes, a new plate cuts quickly.