Diamond stones

[on_the_edge]

Is there an easy and obvious way to know when they are getting close to the end of their useful life and how much life there may be left in them?

 

[Obsessed with Edges]

On coarser diamond hones, probably the most obvious test would be rubbing a piece of smooth glass against the hone, and look for the scratches. Finer hones are usually easy to verify with a blade of simpler steel (carbon steel is easiest), which will leave a lot of swarf on the surface. A wipe with a Windex-moistened rag or towel (microfiber does it very well) will pick up any swarf accumulated, and it'll leave obvious black staining on the rag.

Coarser diamond hones can be easily clogged by low-alloy 'soft' stainless steels. The swarf from such steels is more like the tinsel long ago used on Christmas trees, coming off in long stringy strips (microscopically speaking), clinging to and blanketing the surface of the grit. If the hone doesn't seem to be working well, I'd suspect that first. If it is clogged, a thorough scrubbing with some kitchen cleanser (Comet, Ajax, Barkeeper's Friend), water and a stiff brush can take care of that, most of the time.

It's probably impossible to predict how much life will be left in a diamond hone. Even a hone with some obvious loss of grit can keep working a long time. I have one that gave up some grit in flattening/lapping a ceramic hone; it still handles sharpening well enough.


David

 

[Jason B.]

I have dulled my DMT XXC after 8 years of heavy use and waterstone lapping duty. It still cuts and laps but it has a slick feel to the surface like the blade is skating over the diamonds without them grabbing. That does not mean it has stopped working though, it still hogs off steel quickly.

It takes hundreds of hours and thousands of knives to start to dull a diamond plate. So, unless you have used your diamond plate four or five thousand times it's probably fine.

 

[tinfoil hat timmy]

I have dulled my DMT XXC after 8 years of heavy use and waterstone lapping duty. It still cuts and laps but it has a slick feel to the surface like the blade is skating over the diamonds without them grabbing. That does not mean it has stopped working though, it still hogs off steel quickly.

It takes hundreds of hours and thousands of knives to start to dull a diamond plate. So, unless you have used your diamond plate four or five thousand times it's probably fine.

Good to know! DMT plates are beginning to feel as if they're letting blades slide for them. O.p.... I've bk4 told to use the smooth glass test also.