Diamond stone longevitiy

A

augostos

Joined
Sep 15, 2011
Messages
378
Hello!

I have a DMT fine diamond stone -- a metal base with diamond cover, maybe 1" x 4" size.

My question is, how long it will serve me? Does it wear with usage?

I sharpen maybe one a month a couple of folders, nothing heavy duty.

Thanks a lot
 
I have one that's 20 years old and still works like it did when I bought it. I expect they will last a lifetime.
 
I have a full set of 8x3 diasharps and only the XXC is worn out from lapping waterstones and a ton of bevel setting. If I had not used it for lapping it would probably still be going strong.

I could probably use a new XC plate too, I use it as my main coarse stone for a while before getting the XXC and it too is a bit dull from heavy use. All the others are like new except well broken-in which has made them better.

I sharpen professionally so I use my stones for thousands more blades per year and lapping various grits of waterstones. I've worn out 1 DMT stone in 5-6 years, that's about a lifetime of sharpening for most.
 
My understanding is that pressure is the number one killer of diamond plates. Bearing down on the plate too hard can break the diamond particles out of the surface. Use light pressure, and let the diamonds do the work. On my KME system I have a mix of 4" DMTs and 4" Gold Series plates from KME. I let the weight of the plate and stone carrier rest on the bevel of the knife during sharpening, but I use zero additional pressure. Diamonds will wear in after initial use and feel a bit smoother than they did when brand new, but after that they should pretty well last a lifetime if used properly.
 
I used a DMT Dia-Fold to flatten a ceramic hone a few years ago. That's a tough job for any hone, and it can scrub at least some of the diamond out of the nickel substrate. I spent hours grinding away on it, and could see some darker spots developing in the nickel on the Dia-Fold, apparently showing where some of the diamond had been dislodged. Based on the appearance, I'd thought I ruined it, and I just tossed it into a storage box for a couple or three years. I came across it again, dug it out and gave it a few passes on one of my knives. To my surprise, I found I still hadn't killed it. If anything, it was a bit finer in feel and scratch pattern produced; but it stlll worked well, even great. DMT gained a lot of respect from me, after seeing how tough that one turned out to be. I've since used a larger Duo-Sharp bench hone to do a couple more ceramics; I was a little more careful on that one, in using light pressure and keeping everything submerged in water while I worked. I can't even see any difference in the appearance of the nickel surface, and it still looks like it's new, and performs like it.

Assuming it's from a quality maker like DMT, these are a lot tougher than most would realize. There's a tendency for the coarser diamond hones to collect a lot of swarf, which can clog them pretty fast; more so with softish or 'gummy' stainless steels. I suspect some diamond hones have been assumed as 'ruined' because of this, because grinding performance slows dramatically when they clog; but all they really needed is a good & thorough cleaning to get the swarf out of them.


David
 
Sorry for the mostly related threadjacking, but how do you clean a diamond stone? I have a few old diamond stones (interrupted surface) that are very loaded up, and no amount of scrubbing with clear the swarf. What about swarf that gets into an uninterrupted stone?

I ask because proper cleaning is key to long life, same as pressure control.
 
One of my go-to stones is the DMT Duo-Sharp bench stone. It has seen a lot of sharpening, at times with higher pressures and flattening other waterstones with it. It is still going strong, if at all even easier and more comfortable to use and I am impressed every single time I use it how well it still cuts. Great quality. There is nothing quite like it, it's light and sturdy, very flat and easy to use dry or with soapy water. That's how I use it.
 
dkb45 said:
Sorry for the mostly related threadjacking, but how do you clean a diamond stone? I have a few old diamond stones (interrupted surface) that are very loaded up, and no amount of scrubbing with clear the swarf. What about swarf that gets into an uninterrupted stone?

I ask because proper cleaning is key to long life, same as pressure control.
Click to expand...

I use my diamond stones with soapy water while sharpening (a bottle of water with just a drop or two of dish soap) and at the end I can just rinse the stone off with the tap. No hustle at all. Sometimes I use an old toothbrush to clean it but I doubt it's actually necessary.
 
dkb45 said:
Sorry for the mostly related threadjacking, but how do you clean a diamond stone? I have a few old diamond stones (interrupted surface) that are very loaded up, and no amount of scrubbing with clear the swarf. What about swarf that gets into an uninterrupted stone?

I ask because proper cleaning is key to long life, same as pressure control.
Click to expand...

If they're really loaded up with swarf, scrub them with some Bar Keepers Friend powder, mixed to a paste with water. Wet the hone with water, then apply the BKF paste and scrub it with a toothbrush or similar. Rinse it thoroughly with running water. The oxalic acid in BKF dissolves iron and the oxides of iron; it's fairly aggressive stuff, so read the directions closely and follow them. Used as a paste with water, it'll be dilute enough to scrub for a minute or two at a time, then rinse it off. If it needs more scrubbing, just apply a little more and repeat. The main risk in using BKF is leaving the undiluted product (powder) sitting on steel too long; it can etch steel. On the nickel coating of the diamond hone, or the plastic, it won't be as aggressive, if at all (except on the embedded swarf). Pretty simple to use it, with some common sense applied.

Edit:
For cleaning diamond hones more regularly, assuming they're not loaded heavily, I just scrub with a toothbrush and some dish detergent (Dawn, Ivory Liquid, Palmolive, etc) & water. Rinse with warm/hot water (speeds up drying), wipe it down and let it air-dry for a bit. If done after each sharpening session (I do), it's a cinch to keep them clean this way.


David
 
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Sometimes a diamond plate can look pretty rough yet still work fine, I've had one where (I believe) the nickel tarnished. Plate looked hammered but worked great, under a loupe could see the surface looked fine. For ones that get really loaded, a few drops of mineral oil will release all manner of swarf. I use my diamond plates to true up and sharpen the carbide cutters used to tool my Washboards, a few drops of oil and wipe it off when done, they clean right up. Do not use oil with solvents in it, just like a nickel plated handgun finish, oil is OK, solvents can weaken the plating to the base metal (though only if overdone/left to sit).
 
I wear out my coarse diamond stones pretty fast, but they're the stones that take the brunt of reprofiling, which I do a lot. I must use more pressure than others, but it can take hours to reprofile a super steel with a thick, uneven edge. A little extra pressure speeds up that process. After wearing out my 100-grit Wicked Edge stone from a lot of reprofiling, I replaced them. The new stones cut much faster, although the old stones can still cut metal, just not very fast. I also bought the 50/80-grit stones from Wicked Edge to take some of the burden off my 100-grit reprofiling stones, and even with light pressure, it's a diamond shower when I'm reprofiling with them.
 
The trick to longevity is to work with minimal pressure!

I have a DMT E Fine paddle for over 25 years
Still going strong
I use it to give very light touch ups on my edges to bring them back to very sharp

I also use the DMT Aligner jig
These have relatively small 4" stones on the jig so the wear and tear is very high
I have rebeveled many many D2 blades of Queen slipjoint penknives (a hard steel)
So I have worn out and replaced the E Course stone that does the major rebeveling work on the blades

I clean them with Comet Ajax kitchen cleaners using a damp tooth brush
And clean then off with some water
Very easy
(Comet Ajax is what DMT on their web site recommends)
 
Obsessed with Edges said:
If they're really loaded up with swarf, scrub them with some Bar Keepers Friend powder, mixed to a paste with water. Wet the hone with water, then apply the BKF paste and scrub it with a toothbrush or similar. Rinse it thoroughly with running water. The oxalic acid in BKF dissolves iron and the oxides of iron; it's fairly aggressive stuff, so read the directions closely and follow them. Used as a paste with water, it'll be dilute enough to scrub for a minute or two at a time, then rinse it off. If it needs more scrubbing, just apply a little more and repeat. The main risk in using BKF is leaving the undiluted product (powder) sitting on steel too long; it can etch steel. On the nickel coating of the diamond hone, or the plastic, it won't be as aggressive, if at all (except on the embedded swarf). Pretty simple to use it, with some common sense applied.

Edit:
For cleaning diamond hones more regularly, assuming they're not loaded heavily, I just scrub with a toothbrush and some dish detergent (Dawn, Ivory Liquid, Palmolive, etc) & water. Rinse with warm/hot water (speeds up drying), wipe it down and let it air-dry for a bit. If done after each sharpening session (I do), it's a cinch to keep them clean this way.


David
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Wouldn't BKF eat away at the diamonds and/or plate? Seems like acid would either eat down the diamonds, or eat away at the plating to loosen them up.
 
dkb45 said:
Wouldn't BKF eat away at the diamonds and/or plate? Seems like acid would either eat down the diamonds, or eat away at the plating to loosen them up.
Click to expand...

Most nickel plating is very resistant to acids, as are diamonds. Just avoid cleaners with high solvent content and you're fine.
 
Copyied from the DMT website
http://www.dmtsharp.com/uploads/files/UseandCare_DMTSharpeners_2013rev.pdf

Cleaning and Maintenance
Cleaning and care of a DMT® stone is simple and necessary for best performance.
After using a DMT Diamond Bench Stone or Sharpener simply wet it (if it is not already lubricated with water) and wipe the slurry off with a rag.
This slurry is evidence that the sharpener has done its job.
If the swarf is not wiped off the sharpener after use it may clog up the diamond and not allow it to sharpen as well as it could were it clean.
Also, once in a while it is a good idea to get a common cleanser and scrub the sharpener with a nylon brush or nylon pad.
This will ensure the sharpener is not clogged with slurry and will allow for optimal sharpening. Finally, make sure you store your sharpeners dry after you clean them off.

Overview
 Clean off with rag after use
 Not cleaning will result in clogging
 Scrub with cleaner periodically
 Store dry
 
HeavyHanded said:
Most nickel plating is very resistant to acids, as are diamonds. Just avoid cleaners with high solvent content and you're fine.
Click to expand...

^^This. It's almost inert in most practical uses. The stainless steel plumbing used in industry, in highly corrosive environments, is usually high nickel-content alloy, partly for this reason (it also adds toughness).


(quoted from -->: http://en.wikipedia.org/wiki/Nickel )

"Because of nickel's slow rate of oxidation at room temperature, it is considered corrosion-resistant. Historically, this has led to its use for plating metals such as iron and brass, coating chemistry equipment, and manufacturing certain alloys that retain a high silvery polish, such as German silver. About 6% of world nickel production is still used for corrosion-resistant pure-nickel plating."
Click to expand...

And with BKF, the thing to keep in perspective is, the oxalic acid is still a pretty light concentration in this product (5-10% by weight, according to the MSDS). When used as directed with water, it's even more dilute, and can still be used safely and with minimal risk (HEED the directions on the container).


David
 
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Obsessed with Edges said:
^^This. It's almost inert in most practical uses. The stainless steel plumbing used in industry, in highly corrosive environments, is usually high nickel-content alloy, partly for this reason (it also adds toughness).




And with BKF, the thing to keep in perspective is, the oxalic acid is still a pretty light concentration in this product (5-10% by weight, according to the MSDS). When used as directed with water, it's even more dilute, and can still be used safely and with minimal risk (HEED the directions on the container).


David
Click to expand...

I couldn't find anything about oxalic acid being particularly caustic, but I have had both hydrochloric acid and a strong aerosol paint stripper on my hands, so I'm pretty sure that BKF isn't going to kill . It shouldn't even bother my new neoprene gloves. Since it is safe(ish), I can also use it on an Arkansas stone I have, too.

Since my stones are interrupted, though, would BKF be safe to use with the plastic there? I don't know what kind of plastic they use, could be chemical resistant, could have the chemical resistance of skin. Figured I would ask for me specifically (any everybody else with interrupted diamond stones).
 
I've always used BKF to clean my Damond plates, the plates and my fingers that I use to scrub the plates are just fine. It does not eat at the plate, just cleans the metal swarf off.
 
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