Diamonds Aren't Forever

I'm more of the opinion the plating is the major factor. I've heard many arguments for and against mono/poly. In researching it, monocrystaline is actually less expensive, and poly is what the metallurgical community uses when preparing samples for magnification. Ultimately the plate quality and uniformity of abrasive is more important IMHO.
 
Gritomatic is a vendor here. they have some diamond stones called Venev bonded diamonds. this are really excellent diamond stones, highly recommend after ive used them for a while. so does big brown guy

the KME stones like the beast tho are really good for material removal because the bonded diamonds are not very course, where as the beast is the most course diamond stone i know of.

in any case, using the bonded diamond stones from Venev is much different because its basically a flat surface because the diamonds are embeded into a resin. you dont feel the grit like you do on other diamond stones. but the scratch pattern is amazingly great. much more crisp end result, and easier to remove the last scratch pattern with the next higher grit. best of all they dont cost a huge amount of money. i mean they do if you buy them all, but they range from 15 - 30 a piece depending on the grit for the KME. iirc they dont come flat, so you have to get a flattening kit, but thats pretty easy. the venev stones for the hapston come flattened from the factory tho (so if you have an edge pro i guess those would work too?). @Gritomatic

these do not wear out like other diamond stones also, because they are not embedded on the surface but embedded in a resin throughout.
 
The quality of diamonds varies wildly, so does the quality of plating. I spend a few thousand dollars a year getting diamond applied to my tool bodies to machine stone, quartz, and ceramic, some of these tools are single layer plated. The plating only contacts about 30% of the diamond crystals but the crystals will break before the bond lets go, when done right. I once forgot to screw down a 1/4" stainless steel socket head cap screw and hit it with one of my diamond tools. It pretty much removed the head of the screw before I stopped the cnc router but with a 10x loupe I couldn't see any visible damage to the tool. If I were to get my source to plate a 1"x6" plate it would probably cost $200 with me supplying the plate. Getting diamonds held to a plate with a metal bond is very tricky with expensive tools, I know, I have looked into doing it myself, which changed how I feel about what my supplier charges. I don't cut metal with diamonds but I do cut a lot of hard, abrasive stuff and am always in aw of how long diamonds can hold their edges. I think a properly plated stone with high quality diamonds of the right grade would last forever as long as long as it is not abused. Plated abrasives are by far the most aggressive grinding tools, whether diamond or CBN. The downside is when they get dull there is no way to sharpen, other than to strip and replate.

You want monocrystalin diamond for plating, also called metal bond diamond. You do not want diamonds that will break down under use, you want it to be solid single crystals. Also CBN is for powered machining where heat is a factor, diamond can't take the heat. No need for CBN for hand tools. It is not as sharp, not as hard, and cost's 10x more than diamond when buying powder.
 
Diemaker said:
The quality of diamonds varies wildly, so does the quality of plating. I spend a few thousand dollars a year getting diamond applied to my tool bodies to machine stone, quartz, and ceramic, some of these tools are single layer plated. The plating only contacts about 30% of the diamond crystals but the crystals will break before the bond lets go, when done right. I once forgot to screw down a 1/4" stainless steel socket head cap screw and hit it with one of my diamond tools. It pretty much removed the head of the screw before I stopped the cnc router but with a 10x loupe I couldn't see any visible damage to the tool. If I were to get my source to plate a 1"x6" plate it would probably cost $200 with me supplying the plate. Getting diamonds held to a plate with a metal bond is very tricky with expensive tools, I know, I have looked into doing it myself, which changed how I feel about what my supplier charges. I don't cut metal with diamonds but I do cut a lot of hard, abrasive stuff and am always in aw of how long diamonds can hold their edges. I think a properly plated stone with high quality diamonds of the right grade would last forever as long as long as it is not abused. Plated abrasives are by far the most aggressive grinding tools, whether diamond or CBN. The downside is when they get dull there is no way to sharpen, other than to strip and replate.

You want monocrystalin diamond for plating, also called metal bond diamond. You do not want diamonds that will break down under use, you want it to be solid single crystals. Also CBN is for powered machining where heat is a factor, diamond can't take the heat. No need for CBN for hand tools. It is not as sharp, not as hard, and cost's 10x more than diamond when buying powder.
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Very good post! DMT uses monocrystalin Diamonds and at least in my experience, they last "forever" if used right and they need to be broken in. Maybe there is a quality difference from one DMT plate to another which accounts for different experiences here on BF
 
Could be process variations, err mistakes. My supplier is pretty big and they have had problems. Batches where tool life was 5% of normal, diamonds shearing off at the bond line, patches of bond pulling off of the substrate, cracks in the bond, etc. They went through a period where I was sending a third of their work back. Getting a metal to bond to diamond is really difficult, it is a very interesting subject, especially when your livelyhood depends on it as mine did then.

I have only tried one DMT diamond hone about 25 years ago. It died after a few minuts of touching up some tools, can't say I was impressed.

In 15 years of using diamond tools to make my own products I have discovered for myself that I only plate up to 400 grit, not sure of the micron, because any finer than that and the quality of the plating deteriorates. They just can't get the bond thin enough for such small particales of diamond. Finer than that and I switch to resin bond tools. Granted this isn't for polishing metal but based on some tests I think it still applies pretty well.
 
Just for information, we carry Venev diamond "stones" as well for the TSProf sharpeners. Visit our website at www.statesllc.com and see what we have.

George
 
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My 6" DMT bench stones are still going strong after 25+ years. When they load up, I wipe them down with BreakFree and let them sit a few hours or overnight (preferably). That lifts out the embedded microparticles. Wipe clean with a soft cloth and they cut as good as new.
 
Diemaker, thanks for your contribution in this topic. It helps to explain why some here have different experiences with diamond stones.
You don't plate any higher than a 40 micron diamond grit. That's a medium grit. Humm. DM
 
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