Dia-Sharp diamond stones...

[SamuraiDave]

I have a debate with a friend over if you can wear them out, or if you just wear down the diamonds in it?

Anyone have any idea?

 

[SamuraiDave]

any opinions? Can you wear them down like a normal stone? Or do they cut more as you use them because more of the diamond surface area is exposed as the metal they are suspended in wears down?

 

[Mike G]

Dia-Sharp; Not familiar with that brand.

I use DMT diamond stones, and the manufacturer claims you cannot wear them out, and so far, I believe them. DMT embeds their stones in a nickel matrix, which doesn't wear much either. DMT says they'll replace the stones if they ever fail. These are monocrystaline diamonds, which do not wear very easily.

My stones are used primarily for edge refinement, and quick sharpening jobs on carbide form tools, but I do use them on knives as well.

The DMT stones do lose a little of their 'edge' after time, but as the stones get older, and have more use, they become less coarse, and much better at leaving a smooth edge.

I also use Polycrystaline diamond (PCD) grinding wheels, and those are designed to 'wear away', exposing sharp diamonds as you grind, and as they are dressed & trued.

Hope this helps

 

[Crayola]

Just to elaborate on Code's excellent post,

there are 2 ways of making diamond hones. Either you use monocrystaline diamonds, or polycrystaline diamonds. Monocrystaline diamonds are single diamonds bonded to the base, whil epolycrystaline diamonds are diamond crystals fused to eachother, and then bonded t the base. With the polycrystaline diamonds, the diamonds can break at the fuses and wear out the stone.

Also, I believe people found that using diamond hones in the Edge Pro sharpener would tear the diamonds from the base. I think it was a case of using a lot of pressure, as one could with the Edge Pro system. The diamonds would tear out of the nickel base!!

 

[Walt2]

This could also be a problem with the Ezee Sharp system also.It would be easy to use too much pressure and tear off diamonds. This system is impressive to me. It is designed to use 2"/8" stones but can be adapted to use 6".

 

[Sergiusz Mitin]

Hmm, as to my knowledge all diamonds are monocrystalline, something like so-called polycrystalline simply doesn’t exist. Each diamond particle, even this the smallest, is always monocrystal by its nature, isn’t it? Trying to search this matter, for example the difference between DMT and Eze-Lap sharpening surfaces, I came to consideration that both use the same kind of diamond dust. The only difference is that in case of DMT it has significantly more uniform grain size and better embedding on steel surface what makes DMT sharpeners more durable but also more expensive.

Returning to Dia-Sharp series sharpeners. They have continuous surface as distinct from basic DMT line where the diamond coated surface is interrupted with round, plastic-filled holes. The advantages of continuous surface are:

• It provides better sharpening of very small edges, pointed tools or very strongly curved edges. In fact this is not too essential for knives...
• It sharpens faster than interrupted surface with the same grit because the edge meets more diamond particles at each stroke.
• It sharpens somewhat more uniformly because of more uniform abrasive particle dispersion on the surface (there are no particles in holes at all).

The disadvantage is the higher price of continuous (Dia-Sharp) sharpening surfaces in comparison with basic ones.

OK, finally the original question – can they wear out? This depends on what exactly you are considering as wear out. If you think about loss of flat surface and coming concave in lengthways direction and convex in crossways one like it occurs with natural stones – no, they can’t. Simply because the diamond-filled layer of nickel over steel what makes abrasive surface is very thin and there are no space where to come concave or convex.

However if you are speaking about loss of abrasive properties – yes, they can. Relatively soft nickel plating will wear out and lose more and more diamond particles until entire surface will come totally bald. This is theory, I suppose that properly used DMT sharpening surface could outlive you and serve your sun as well.

But be careful – it is possible to cause fast wear out using too much pressure when sharpening. It is impossible to break diamond particles as themselves, however it is possible to dig them out of relatively soft nickel plating destroying expensive sharpener irreparably.
In fact it is not necessary to apply any hard pressure when sharpening. Diamond particles have much sharper edges than any other abrasive ones and they do their job well even at relatively light pressure.

 

[Cliff Stamp]

Sergiusz Mitin :

all diamonds are monocrystalline, something like so-called polycrystalline simply doesn t exist.

The polycrystalline diamonds are aggregates of individual crystals that are angstrom in size (0.0001 microns). The monocrystalline diamonds are grown and not combined and are much more resistant to fracture.

can they wear out?

DMT guarantees their stone against wearing out, one of the few who does. I have a large DMT rod that is many years old and is one of my more frequent sharpening tools. You can however damage them easily under high pressure.

-Cliff