Thread: Lapping a Chinese 12k

Originally Posted by Russel Baldridge

Was it saturated with water? Though, soaking shouldn't make that much of a difference.

Maybe your stone was more uneven on the surface you lapped. Because the time it took to lap it could mean either it is very hard, or that it was really uneven.

How much slurry was produced?

Good questions:

I did not soak it prior to lapping. It seems odd to me that even the honing directions advocate soaking that stone for like 30 minutes. It does not seem like a porous stone to me.

You're correct, the middle was much higher than the ends which made for why it took so long (had to remove most of middle to even it out).

It did produce slurry during the lapping and I kept the stone/plate plenty wet while lapping. Still, it's the hardest natural stone I own, much harder than my yellow coticule, belgian blue, Tam O' Shanter.

Chris L

Yeah, it's a porous stone, but I've heard a number of people say that using it dry, or with just a splash of water on top is fine.

But I like to soak it, then build a good amount of slurry with a 600 grit 6"x2" diamond hone do about 30 strokes, rinse it off and do 20 to 30 more as it dries. Gives a great edge, and a lot faster than when I just kept it wet.

Does this imply that there are different grades of the chinese 12k? I would assume so because it is a natural stone, but no one really seems to mention it around here.

Woodcraft seems to carry one type: http://www.woodcraft.com/family.aspx?familyid=4920

Has anyone gotten theirs from them? Or where did you guys pick yours up?

I got mine at Woodcraft. They only have one grit chinese stone. It's the 12k one. 2 sizes though.

Also, I never use water when honing on mine

Same as mine also, this one does not soak at all, It is very dense.
Lapped it on D8C, was fairly ok to get it done.
(I'm lapping an Shapton 16K on the D8c now, and THAT is pain)

I seem to recall that the Shapton stones are known to be very
difficult to lap, though not as much as the Spyderco hones.

Dr. Chris Moss used to lap his Shaptons with the DMT, but got
a Shapton DGLP to make it easier and quicker. I believe he has
had quite a lot of success with the lapping plate.

- Scott

Yes, and I'm a bit worried if my D8C was ruined in the attemt, I have used the whole evening lapping that shapton, and still there are a bit in the corners that is not lapped. It feels like the D8C is full of ceramic now, tried to wash, but..

I have read about the DGLP, and maybe I have to give in on that, wonders how fast is it to lap an shapton with that?
And, I guess the DGLP could be good to lap everything else?, like the Chinese12K, Coticule etc?

Originally Posted by asbjorn

Same as mine also, this one does not soak at all, It is very dense.

Mine soaks up water just fine, takes a while, but it does soak.

The chinese 12k comes in one "grade", 12k. I got mine from Woodcraft and it is the larger size.

I also got the larger size from Woodcraft.

John

I got the smaller size from Woodcraft and it does make a slurry within 15 passes or so with a chisel or razor.