DMT D8C wear from lapping?

[Moog101]

Hi all

A couple of weeks ago I got a whole bunch of honing stones and some DMTs.

I started out by lapping my Norton 4000/8000 and all was fine with the DMT DC8.

Next I started lapping my SpyderCo 12k (which I know there are mixed opinions as to if you should actually attempt this as it should already be flat) I've spent about 2 hours trying to lap this stone, and probably it's going to take another 2-3 hours to finish.

The question is, I recently received a second DC8 and out the box brand new it's a LOT rougher to the touch than that one I've been using for lapping. Have I ruined my original DC8 by trying to lap such a hard stone (the SpyderCo) or is this sort of "breaking in" of the a DMT normal?

Thanks

M

[Zeni]

My DMT 600 and 1000 have just "broken in", I think it is normal.

[joke1176]

Just putting in my two bits here: If it cuts a little slower than your new D8C, but still does the job, that's what I call "breaking in".

If it doesn't cut anymore, or cuts slower than a stone of the same grit, it's worn out.

Mine went through the same process, but it still cuts ok. Just not as fast as before.

[Moog101]

Thanks guys.

The older one still feels rough to the touch but only about half as much as the brand new one.

Knowing that diamond is virtually indestructible I was just a bit surprised that rubbing a stone against it would make it so much smoother.

Cheers

M

[xChris]

Even though the DMTs use diamonds, you need to be careful about the pressure you apply in their use. Nickel is usually used as a substrate to bond the diamonds to the steel plate. If you apply too much pressure, you can actually dislodge the diamnds from the nickel substrate and into the piece that is being honed (e.g., razor or knife blade). Diamonds don't need a lot of pressure to do their work.

After saying that, since it was ceramic instead of regular metal that you were honing, I'd say it's probably just the "break in" of the hone like others have already said.

[matt321]

Some things I've read on forums about DMT's:
When new they are coarser and more aggresive than their rated grit.
They should be used with light pressure as heavy pressure can damage the abrasive,
i.e. you can knock the diamonds out of the matrix they're imbedded in.
Use on soft metal blades can cause pull-out of the diamond crystals.
When used to lap waterstones allowing thick slurry buildup can wear away the nickel matrix.