Thread: Lapping stones

I have been using an old mirror and sandpaper to lap my stones quite successfully but I was burning through sandpaper. I purchased a DMT D8C and used it of the first time last evening. I must be doing something wrong as what seemed like a perfectly flat lapping stone has gouged my norton 4k on my first attempt. Any suggestions would be greatly appreciated.

Jim

Brand new they come with some of the diamond grit high on the plate. You should take something like a screwdriver or any hard piece of metal and rub the face to knock down the high spots. You will feel the difference with your hand. You will see it when you lap again.

I had the same problem and the solution is as 10Pups says. They should come with a warning about that a description of how to break it in to cure that. Annoying does not begin to describe it.

Bob

Luckily, a kind forum member told me that when I posted that I had one in the mail. I used the shaft of a screwdriver to run back and forth from end to end along the DMT probably 15-20 strokes, and you could hear it hit a high grain of diamond or 2. Once it made a consistent sound, I lapped my Naniwa 12k under running water until my pencil grid (tip courtesy of Lynn's video). It works, and my 12k now feels as smooth as glass. You and your stone will recover, but I too would have been annoyed.

Screwdriver worked awesome. Wish I would have asked yesterday

i currently use a dmt8c for lapping my naniwas
It work very well with dry naniwa stone (very fast and very good job) . I have only a problem : clean dmt is diffucult when I lap naniwa 12k because the fine particles of naniwa12 occlude interstices and them are very diffult to remove

Originally Posted by kratos86

i currently use a dmt8c for lapping my naniwas
It work very well with dry naniwa stone (very fast and very good job) . I have only a problem : clean dmt is diffucult when I lap naniwa 12k because the fine particles of naniwa12 occlude interstices and them are very diffult to remove

Cream cleaner (in the UK the popular make is called Jif) and a green scouring sponge, it will come right off

Glad to hear it's sorted. I've had one for a few years, I bought it second hand, and they really are versatile. Only the saddest of razors see it and only the hardest stones avoid it but shaving aside I find it invaluable for sharpening knives & tools, a little soapy water or a few drops of oil makes it a little nicer to work with. It saved me a load of time & effort recently when stripping old paper off the ceiling, I think it took around ten seconds every few mins to keep the edge of scraper flying through the work instead of me fighting the ceiling.

Originally Posted by Proinsias

It saved me a load of time & effort recently when stripping old paper off the ceiling, I think it took around ten seconds every few mins to keep the edge of scraper flying through the work instead of me fighting the ceiling.

I had a picture in my mind then of you rubbing the stone on the ceiling and thinking its a bit heavy, surely that's not easy !! Then I read the rest and gave my head a bang for been a dumb ass

Originally Posted by BobH

They should come with a warning about that a description of how to break it in to cure that. Annoying does not begin to describe it.

Bob

DMT doesn't want you using the D8C for lapping. They want you to spend a lot of $$ and use their Dia-flat lapping plate. No thanks, the D8C works just fine.

I spoke with DMT customer service over a year ago, when I first got my D8C, about dark spots on it. She asked me what I was doing with it. I told her that I lapping other stones. She said that she'd been getting calls from customers who have been doing the same thing. She then said that the D8C shouldn't be used for lapping, and that I should buy their "special" lapping plate. I told her that I'd keep that in mind. She helped me clean up the dark spots, though.

Also, sharpening a wide chisel on a new DMT gets it broken in fast.