Thread: Help with Chinese 12k

I recently got a Chinese 12k from Sparq. I lapped it up to a 1000 grit paper to make sure that it was flat and smooth.

When I finish with my Naniwa 8k, the bevel is very shiny and smooth. Mirror like. When I begin to use the C12K, the bevel looks scratched up and courser than it did with the Naniwa. I am using only water and light pressure.

Am I doing this right? Should I be using slurry? I am just looking to further polish the edge.

Any chance that random grit from the sandpaper contaminated the stone ? Just a thought.

I hope not, I lap under running water and then give the stone a good rubbing by hand under running water as well to make sure that it is nice and smooth and free of debris.

Did you round the edges of the stone? If not that could be the reason. I think the C12K is to hard to get particles of the sandpaper embedded into it.

Good luck with your stone.

Skizzo

Forget what the bevel looks like, how does the edge cut?

I just tried the stone again. I soaked it a little longer this time and the bevel seems to be much smoother. I'll giv'r a workout tomorrow and see how it went.

Originally Posted by dnjrboy

I just tried the stone again. I soaked it a little longer this time and the bevel seems to be much smoother. I'll giv'r a workout tomorrow and see how it went.

I bought one from Woodcraft. I haven't used it much but when I did it left a good edge. I didn't really pay any attention to scratches one way or the other. I noticed that on the box it came in they said to soak the stone.

Here is an old thread where I posted a photo of the instructions and asked others if they soaked theirs. Most do not but I like to follow the instructions so I do. I don't know if that would make a difference. Might be worth a try.

Member experimentation has found that there is no benifit to soaking the stone. It's too dense for water to soak in. Someone soaked one and cut it up, but you should be able to tell with your own that it doesn't soak up water.

My C12K will leave a hazy finish to the edge as opposed to the mirror polish of other stone (lime your Naniwa or my Norton 8K). Just a charateristic, so as long as your edge feels good, I wouldn't sweat it.

The other thing to remeber is that most of the C12K stones are slow cutters, so many more strokes are required to get the edge up to the stone's full potential.

Originally Posted by holli4pirating

Member experimentation has found that there is no benifit to soaking the stone. It's too dense for water to soak in. Someone soaked one and cut it up, but you should be able to tell with your own that it doesn't soak up water.

That seems like a... destructive way... to test that.