Thread: DMT 325 question

Greetings hone gurus,

I recently purchased a set of hones norton 220/1000, norton 4k/8k, and dmt 325.

I used the dmt to lap the nortons apart from the 220 and also a small Chinese 12k.

Just yesterday I found a few bright spots on the dmt and if it feels uneven. Has anyone experienced the same problem?

Oh, I bought the hones from SRD.

cheers,
sy

DMT (and SRP, too) recommends breaking in the lapping plate before using it. Sometimes there are high diamond spots, which will scratch up the hones you are trying to lap. Take a screwdriver shank or something similar and run it across the DMT for a few minutes, or you can hone some kitchen knives with it.

PS - No, you are not the first person to experience this, it has happened to many.

Couple things I do with mine,as above I sharpen my lathe carbide cutting bits on a new plate,I also chamfer the edges in a standard bench grinder,works for me.

When I got mine out of the box, I dropped it on my bare foot. I gave it a good cussin' and it's been dead flat ever since.

I think I haven't made myself clear.

I didn't break in the DMT as I didn't know I should. I lapped the nortons which came out okay. the DMT darkens after the lapping sessions.

then i noticed the bright spots on the darkened dmt. they feel like dips or holes on the dmt. i'm wondering if the diamond particles dislodged or something.

sy

Originally Posted by ace

When I got mine out of the box, I dropped it on my bare foot. I gave it a good cussin' and it's been dead flat ever since.

Ouch!!! That sounded really painful.

If you used pressure while lapping you could definitely have dislodged some of the diamonds from the nickel plating.

Originally Posted by gnoils

Then i noticed the bright spots on the darkened dmt. they feel like dips or holes on the dmt. i'm wondering if the diamond particles dislodged or something.

sy

I see... it does sound like some diamonds became dislodged. I'd say you got a bunk stone (it happens), as the DMT 8C is no wimp when it comes to use, they can take some punishment ie pressure. Try contacting the vendor about an exchange. They may refer you to DMT directly, though.

How much pressure did you use, and how often did you rinse the stone and the DMT? It is easy to kill these lapping plates with excessive pressure and letting the swarf build up like mud on it.

If the areas are really tiny and you use a figure 8 pattern while lapping (which you should)Will not make a hill of beans differance.