DMT break in thread..

[Dups]

Hey guys,

I remember reading something about breaking in a DMT but just can't find it..

Help please

thanks

JF

[Sticky]

I copied this from here:

I use a piece of hardened steel. Usually either a piece of tool steel or the flat body of a chain breaker. A chisel body is another good piece to use, anything hard and close to flat is good. Use lots of water and fairly light pressure. I usually give it 30 to 45 minutes of all-over coverage. If it still feels too rough, give it another 30 minutes or more.

Sharpening kitchen knives is good too. I haven't personally tried it with slurry yet.

Other posts in the linked thread have more good info on DMTs.

[sebell]

I had a hard time breaking in my D8C in this manner, it
was not smooth enough to lap a natural stone after an
hour or more of this. Lapping a hard ceramic hone did
the trick, but at possible risk of damaging the DMT.

I experienced the same difficulties with the D8E and
D8EE, I couldn't get them smooth enough for a razor
at all.

I hope it works well for you!

- Scott

[Rajagra]

Some important DMT quotes:

Break-in period: Initially your diamond stone will seem especially rough. It will smooth over time with gentle stroking without impacting performance. You need not exert extra pressure - let the diamonds do the work!

Double-X is perfect for flattening water stones, Arkansas stones, and synthetic stones.

Coarse and Extra-Coarse Grits may be used with a flowing water wash to quickly flatten conventional and water stones

An interesting link.

DMT is a bit vague about why breaking-in is needed and how it is done.

I suspect the steel plate is perfectly flat, but the nickel coating and diamonds it contains go on less precisely. Breaking-in must mean removing any high spots of nickel/diamond. I'm a bit unclear how light strokes can achieve this. A piece of steel isn't going to wear out the diamonds using light strokes!

I have to conclude that the aim is to break off diamond at the high points, and wear off the excess nickel below.

Lapping a hone certainly breaks in a DMT well (too well if you don't follow the precautions!), but it also wears the DMT plate down. Sadly, we have to accept that breaking in a DMT is the same thing as wearing it out. This is a very bad thing for craftsmen sharpening their tools. It isn't as bad for us as we'd need to hone a huge number of razors to wear out a diamond plate.

[Dups]

What did you guys use to break yours? I don't own chisels so something else might be better for me?

[Sticky]

...
DMT is a bit vague about why breaking-in is needed and how it is done.

The vagueness is because there are many different ways to do it. Do it through normal use, or speed it up by using hardened steel. For faster break-in then hardened steel, use some boron nitride tooling or flat ceramics.

...
I'm a bit unclear how light strokes can achieve this. A piece of steel isn't going to wear out the diamonds using light strokes!

The light strokes are so you don't tear the diamonds from the nickel. Light strokes also help minimize media-loading, and give best results edge-wise. The diamonds will wear in long before they wear out. Diamonds are a bit like any machine tool, too heavy a feed-rate or working pressure will give bad results.

...
Sadly, we have to accept that breaking in a DMT is the same thing as wearing it out. This is a very bad thing for craftsmen sharpening their tools. It isn't as bad for us as we'd need to hone a huge number of razors to wear out a diamond plate.

A good analogy would be that a car (or the engine in one) will last much longer if correctly broken-in and maintained. I've been using the little red WMF (less than 4 sq.inches of working surface) in my avatar for over 22 years on thousands of tools, some high tech (extremely hard) tooling, knives, and razors. It looks like there are at least another 22 years still in it. Of course, I broke it in well, give it regular maintenance, and do not "drive it" past it's capabilities.

For the more technical questions, there is:
Stan Watson
Technical Director
Diamond Machining Technology
T 508 481 5944 ext. 228

[Dups]

thanks sticky!

Could I use a big kitchen knife to break it in or some kind of abrasive?

[Sticky]

...
Could I use a big kitchen knife to break it in or some kind of abrasive?

An old kitchen knife laid on it's side will break it in more evenly. Sharpening knives normally will also work, but will take longer because less of the knife is on the hone at one time.

Maybe the side of a long screwdriver? An old planer blade? I prefer hardened steel because it works faster. A ceramic barber hone or Spyderco will do well; just remember to keep the slurry rinsed off.

Don't use abrasives like lapping compound or slurry.

[Dups]

I have an two barber hones, a swaty that I use and an unknown one that I don't really use.

I also have many kitchen knives. What do you mean by laying it on its side? Sort of like you would do with a razor?

Does it take a long time to do? I've heard that you want the plate to get sort of shiny?

[Sticky]

I have an two barber hones, a swaty that I use and an unknown one that I don't really use.

I personally have used both Swatys and white Spydercos to break in DMTs. Due to the recent problems that some members have had with slurry damage to the nickel, I would recommend hardened steel to anyone else. Translation (without disclaimer): At your own risk...

I also have many kitchen knives. What do you mean by laying it on its side? Sort of like you would do with a razor?

Yes, 1 to 3 pounds of downward pressure is enough.

Does it take a long time to do? I've heard that you want the plate to get sort of shiny?

For the hardened steel that I use, about 30 to 75 minutes. The DMT surface will tend to look "splotchy" and streaky. Mine start to darken, using the steel that I have. Use plenty of water. Clean afterwards with comet, zud, ajax, etc...