Thread: DMT 325 or 600 for lapping coticules?

Of the 325 (D8C) and 600 (D8F) which one is more ideal for lapping coticules? I'm on a budget.

If cost is an issue, 600 W/D sandpaper on a very flat surface (like glass or a scrap marble countertop chunk) works as well as anything

The 325. The DMT hone series never was intended for lapping but the more coarse grits survive better. The 325, as long as you do not abuse it will serve as a workhorse for a long time.

Originally Posted by Utopian

The 325. The DMT hone series never was intended for lapping but the more coarse grits survive better. The 325, as long as you do not abuse it will serve as a workhorse for a long time.

And it's fine for lapping coticules?

Yes, but like any other lapping with it, do it under running water, just use the weight of the hone, and frequently remove the hone to rinse out more of the accumulated swarf.

If you only want it for coticules though, I second the sandpaper suggestion. Coticules don't need to be refreshed, and I highly doubt even with frequent use you would need to lap it more than once a year, so the slight inconvenience of the sandpaper is highly offset by the huge price savings. A lapping/refreshing plate is a convenience but not a necessity for natural hones in my opinion.

Coticules and Eschers are about the only natural stones I would consider lapping with a DMT as they are fairly soft.

I 3rd the use of sandpaper, it's cheap and it works

I have both a dmt 325 and a granite lapping plate for using sandpaper, and I use the dmt much more often because it is far easier. I use it for stones all the way to 10k grit.

Not sure what they have on their site now, but Dia-Sharp (DMT) used to have a FAQ that said any plate above 325 grit was NOT suitable for lapping waterstones. Doing so will take the nickel plate that holds the diamonds off. The 325 is alright if used with running water. They really recommend the 120 grit for lapping, but I've used the 325 for years and it is still going strong. Also doubles as a sharpener for my kitchen knives.

Try the 400/1000 combo plate from Chef Knives to Go, $35. It is a full 8X2.75 plate in a diamond pattern to prevent stiction.

400 will easily lap naturals and synthetic stone. The 1k is great for restoration work.

I have been abusing one for about a year now, with no problems.

Originally Posted by Euclid440

Try the 400/1000 combo plate from Chef Knives to Go, $35. It is a full 8X2.75 plate in a diamond pattern to prevent stiction.

400 will easily lap naturals and synthetic stone. The 1k is great for restoration work.

I have been abusing one for about a year now, with no problems.

Is it flat like a DMT?