Edge Pro Matrix resin bond diamond stones

These stones are perfect for ceramic knives. My only suggestions are edge trailing passes only, no micro bevels, and watch out how low of an angle you can go. Ceramic likes to microchip so that limits my one ceramic knife to 21 degrees per side. This is based on my experience with one ceramic knife so micro bevels and angles may change.
 
You can probably do without the 80 and 4000 grit. The 120 grit SiC stone is usually pretty good for reprofiling and hogging off just about any steel. I like the 4000 for polished edges though, the 3000 grit polish tape does a better job of getting a mirror polish, but the 4000 grit matrix stone is better at keeping a nice crisp edge on steels like s30v and whatnot. Before I had the 4000 grit stone, I'd load up my 3000 grit polish tape with some 1 micron diamond compound and do a few edge trailing passes on each side to finish up if I really wanted a stupid sharp, hair splitting edge.
 
I have dressed Shapton Glass stones with Matrix stones and it worked for both very nicely. I have also dressed some Matrix stones on an EP 1000 with good results so I don't think what you use matters too much, it just needs to be flat and at least as big as the Matrix stone. To dress a Matrix stone this way use a little water to develop a slurry, it shouldn't take more than 10-15 seconds of rubbing the two stones together to clean up the Matrix stone. I think this is a viable method of dressing the 650 and finer Matrix stones, it certainly is a lot less mess than using loose abrasive on a plate.

A while ago I ground some different "granite" tile pieces flat to see if they would work as dressing flats for Matrix stones, just haven't tried them yet.
This is great news for me. I'd much rather use other stones than powder for dressing. I'm thinking match the grit up to 600 or so and then use a 600 for dressing everything over the 650. I have a cheap 400/1K diamond plate. Would you suggest using that?

OK, I got done with an extended period with the Diamond Matrix stones and was all sorts of psyched about them (still am). But instead of doing an immediate review I decided to wait and go through my regular stones again while it was all fresh in my mind. For reference, I’m using a Hapstone M2 and recently got to use the new bearing upgrade for the main slide rod, but that's a different review, lol.

My normal stones are the SIC stones from Gritomatic 120,240,600,1000,2500 I also have the standard set of 220,400 and 1200 that came with it. I thought that using both for extended periods would give me a better basis for comparison.
I think the best way I can describe the Diamond Matrix stones is smooth and “respectful”
The 80 and 250 stones are NOT gonna “hog off metal” like I’ve seen described of some stone in that range but they do remove it faster than My SIC stones for sure! One of the biggest differences is the scratch pattern I see after using them. It is sharp and defined and no gouges or overly deep stuff that I have to get rid of with the next stone before it gets to do its thing. And you don't need undo pressure to make them work. No leaning into or pressing down on the rod to get results, its just casual movement.
Now to where I see the biggest change! 650 on up…. Most of my knives don't need a re profile or have deep damage to them so for normal use I would start at 650 or higher. The first few knives I did I used the standard back and forth movement and they work fine. Much easier and faster than the sic stones. Already I’m a believer. But I have a tendency to be light on pressure anyways and don't get big honkin burr’s on the apex like some talk about. On a whim, I just started using trailing edge strokes after that.
BAM! I started getting burrs in half the time and could remove it in 1-2 stroke on the other side.
Now part of the comparison...I still don't get results like that with my sic stones after going back to them. Works great on the DM stones, not on my sic’s….. Maybe its just me, but I like easy!!
The 650,1200,2300,4000 all remove more metal or should I say they produce an edge much faster than I would have thought at a reduced pressure too. The scratch pattern is smoother and tighter than normal due to improved grit pattern in the stone,epoxy, pancake batter, what ever he’s using.
This all part of why, at the beginning I called them respectful, in case you were wondering about that. It becomes a process that takes off the metal and shapes the blade, but in a way that doesn’t abuse and gouge the steel. Respect is the best way I could describe it. I can’t fault my own stones at all, I enjoy using them and get great results with them. But the Diamond Matrix Stones really are an evolution in guided sharpening stones and I don’t know if he’s lucky at finding this solution or a good designer or what, but I’m glad he did and I am gonna put buying knives on hold for a bit to spring for these. It’s the real deal.
Nice review. The scratch pattern from this is crazy good. I can get an 80 grit edge that will cut paper. I can cut newsprint off the 240. I think the not hogging off metal quickly also means it's not destroying your edge in the process. The trailing strokes thing was a eye openers for me as well. It's transformed my EP sharpening in terms of time to get to a great edge.

You can probably do without the 80 and 4000 grit. The 120 grit SiC stone is usually pretty good for reprofiling and hogging off just about any steel. I like the 4000 for polished edges though, the 3000 grit polish tape does a better job of getting a mirror polish, but the 4000 grit matrix stone is better at keeping a nice crisp edge on steels like s30v and whatnot. Before I had the 4000 grit stone, I'd load up my 3000 grit polish tape with some 1 micron diamond compound and do a few edge trailing passes on each side to finish up if I really wanted a stupid sharp, hair splitting edge.
Agree - most won't need the 4K or even the 2K stone. But I like them. I have no need for a 6K or 8K stone, but I'll get that as well when/if Diemaker produces one for EP. If you're trying to reprofile Maxamet, K390, or other hard steels you're going to want the 80 grit. Getting my Spyderco Mules to 17 degrees would have taken a long time with the 250.
 
I have played a little more with dressing the Matrix stones on flat stones. What I used were "granite" tiles I machined flat since the only bench stones I have are for deburring flat surfaces in my machine shop and are NOT used for anything else. They worked ok, developed some mud, and cleaned up the Matrix stones ok, just ok. The ends of the Matrix stones are not getting cleaned up very well but otherwise look good. Still, I think stones are much better than sandpaper. I am back to "loose abrasive on a flat plate is by far the best way to dress Matrix stones", nothing else is even close. Here is a photo of the Matrix stones on the stones I used to dress them, please dis-regard the water spots. I spent a lot more time dressing on the stones than I would have if I had used loose abrasive.

Stone-Dressing.jpg


I finally measured the Matrix stones that EP uses daily, something I am supposed to do every May but it just hasn't worked out. Unfortunately, I didn't write down what they started out at on my list, this info is engraved on the stones, but have a good idea of where they started so I will give my best estimate here and edit it once I get the info. They started using the 250 through 1100 grits about March of 2018 and the 80 early February of this year.

80 grit - lost .001" in 6 months, but they don't use it very much.
250 grit - lost around .003" in 17 months
650 grit - lost around .015" in 17 months
1100 grit - lost around .014" in 17 months
2300 grit - lost around .004"-.006" in the last 15 months
4000 grit - lost around .002" in the last 15 months

Cody did say about a month ago that he figured they were going to show a lot more wear as he has taken to dressing them after every 5 knives or so as he likes how they work after a fresh dress. They keep their dressing plate next to the sink, which is next to the sharpening station so it's real easy for them to give the stones a quick dress. They sharpen around 50 knives a week and use the Matrix stone most often. With proper care and dressing, I would think the wear rate could be reduced by 80% or more. If you want the stone to cut faster just use the next coarser stone since freshly dressed stones leave deeper scratches anyway there isn't that much difference.

I really don't think using a diamond plate to dress the stones is a good idea. It may kind of work because your only really removing resin on the Matrix stones but it will be hell on your diamond plate. Even if it works well at best it will be 20% as good as loose abrasive on a flat plate, which is about where stones and sandpaper lie.
I have made Matrix stones with diamond down to 1 micron but they really only work down to 5 micron, or 4k grit, on steel. On ceramic knives, the 2.5 micron works really well. If you want to go finer then I suggest doing it with a strop, which is what I do.
 
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That's really interesting, and helpful.

Usually I got to my 3 micron and .5 micron diamond lapping films, and .25 micron strop after the 4k if I want a stupid sharp edge, so I guess that makes sense.
 
Diamond films sound like a good idea. I often use diamond compound on balsa or bass wood strops. Polishes ok and gives a sticky sharp edge on the right steels.
 
Using diamond to lap diamond stones is a no no. The objective is to wear down the binder to expose fresh abrasive, a diamond stone will wear down your diamond abrasive a long with the binder. AlOx nagura stone is good to go, or loose SiC powder.
 
I agree with Baron Mind don't use diamonds to flatten diamonds,because the diamonds are the same hardness you will damage them,you just trying where back the binder as mentioned already.

Diamond films sound like a good idea. I often use diamond compound on balsa or bass wood strops. Polishes ok and gives a sticky sharp edge on the right steels.
 
The Matrix 4k stone is 5 micron diamond. I found 2.5 micron to be too big for the strop after the 4k stone, 1 micron seems to me about right to a tad small. I have some .1 micron diamond on a leather strop and it doesn't do much after the 1 micron and I am looking at it under a microscope. One big problem with this fine abrasive is contamination on the strop, it doesn't take much and you will find stray scratches on your bevel comming from the strop. Make sure to keep one plain clean leather strop in your kit. It may not be good for eye candy/polished bevels but it is always great at cleaning up the apex to get it just that little bit keener. IMO no need to pay for polycrystaline diamond, as it propbably won't break down on a strop anyway and the monocrystaline won't stay on the strop long enough to dull. The powder is about 10 times the cost of monocrystaline.

I don't think the EP tapes will do anything to Maxamet, I know alox stones don't do squat.

If you get EP polish tape blanks get the hard anodized ones, the extra cost is well worth it. Disclaimer- I don't make anything on the anodizing, just love the performance of HARD anodizing.
I think I read somewhere that the 2k and 6k tapes are silicon carbide, only the 3k tape is Alox. No idea why. Saw that on a post in wicked edge's forums.
 
I finally bit the bullet and got a Matrix 4000.
5 micron ? That's hungy.
I almost got one from that other outfit. They claimed the diamond grit for the 1200 grit FEPA-F is 2.5 micron.
I almost pounced on it since the price dropped to ten bucks less than said Matrix 4000.
At the final hour cooler heads prevailed (I read the Matrix produced a really clean high polish).
It does !

Still . . . just looking at the specs I almost want to get the 1200 / 2.5 just to prove it to my self.
That would be really dumb right ? !

Anyway my very first stone of diamonds mixed in with the solidified goop is a Matrix.
I feel good about that and am glad I got it.

Diemaker :
Thank you thank you for engraving the plate with the girt size ! ! ! ! !
And so nicely executed to boot ! !
Why the heck the Shapton Glass stones etc can't seem to get real and do that I don't know. I get tired of writing the grit size on with magic marker. I wonder if the stones would survive a session with my buzzy "engraver". Might be a bad idea.

So far the only knife I have used it on is my Para2 M4. He took some minor damage on the belly while cutting hard rubber that had some grit in it. I could just see reflection on some intermittent edge anomalies.
On a lark / test I decided to try the Matrix 4000 alone to fix the edge. Initially I went on the sharpening bevel and it pretty much took out the damage ! ! !
Still it wasn't as hair destroying as the rest of the undamaged edge so I went up a degree or so and went for the faintest micro bevel just to see what would happen.

End result : surprisingly sharp edge (Whittling) considering I didn't do the smart thing and use one or two more coarse stones first.

The stone took some tiny scrapes in a couple of places, probably from going edge leading with a little too much zeal though I wasn't using much downward force at all. Mostly I used edge trailing but some edge leading.

The sharpening results I am am very pleased with.

If there is any con I would say the stone is crazy hard to clean.
While sharpening I used a rust eraser pad (the gray ones with the Japanese characters on them ).
Marginal success with that. Then I added unscented dish soap with the eraser. That was a little better. I tried rubbing alc. That seemed to do nothing . . . at least initially . . . with some time and multiple applications it started to wake up and took off a good bit of swarf but it sure wasn't like cleaning any of my other stones which is fairly quick bordering on instantaneous.

I used my natural Nagura and that worked some what.

Kind of frustrating on the cleaning aspect. Man it gets black / dark gray and just hangs on to it.
Still . . . the stone does it's job I must say.

An interesting experience.
Thanks for making such fine stones.

PS: no way to just mix the diamonds into what ever goop Norton uses in their yellow 8,000 stone ? ? ? ? ?
Something tells me that would be the best stone on the planet . . . at least for me.
 
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I found that 90% or higher helps. They come clean with a little elbow grease and paper shop towels. Usually about 30 seconds per stone to clean them. I also follow Diemaker's process and clean them under water with my thumb right after sharpening. That gets most of it. The alcohol gets the rest. I posted some pic earlier in the thread.
 
I found that 90% or higher helps. They come clean with a little elbow grease and paper shop towels. Usually about 30 seconds per stone to clean them. I also follow Diemaker's process and clean them under water with my thumb right after sharpening. That gets most of it. The alcohol gets the rest. I posted some pic earlier in the thread.
I was using my finger with 90% (sorry I said rubbing alc; it was 90) and the finger did seem to grab swarf better than the rust eraser. I would never have believed that. It's curious how it takes a while as if the alc is very slightly devolving the stone but it takes time to happen.
Is there any validity to that or is it just breaking down surface tension or what ever like soap might normally do ?
 
Not sure why it seems to take some time. I'm also very generous with the alcohol and I really lean into it with a shop towel. I don't use a single layer of towel - I wad it up and saturate it with alcohol. I also move to a clean section once it gets dirty. So I'll do a few passes, rotate the paper towel wad, a few more passes, and keep doing this until the towel is no longer getting dirty. It seems like a clean section of paper towel works better. I'm guessing it's picking the material up off the stone rather than just moving it around.
 
As has been said many times before, don't read too much into grit size. It really doesn't mean much. The older Venev 2000 diamond stones left a similar scratch pattern as the Matrix 2300. I have made finer grit stones, they don't work very well. I have seen the same problems in other finer grit stones, including Shapton Glass. In my experience the SGs peak around 8k to 16k, the 30k degraded the apex. If you want to try them then try out the pass-around kit and I will add them to it. I will warn you though, if you try out the full set and see how much better they work as a full set you may be in trouble $$. My solution for finer stones is leather strops, which I added to the kit some time ago. Bare, 1-micron diamond, and .1 micron diamond.

Your engraver shouldn't hurt anything, it sounds like the one I have. Generally, the adhesive used to glue stones to aluminum blanks is not brittle. I would suggest putting your stone on a soft surface to absorb some of the vibrations when engraving and take your time. The sharpie works best on the end of the stone vs the aluminum back. I ran into the same issue with EPs set when I played with it.

Edge trailing strokes are not only good for the knife it's a lot safer for the stone. Good news is the scraps don't hurt the stone, as for the knife, well it's not so good for it.

Alcohol does not attack the resin at all so it is safe. Other solvents will attack it so ONLY use alcohol and NOTHING else. As David Richardson said use other areas of the paper towel and keep at it, it will clean up generally in 1 minute or so. The stronger the better, which is true for other uses for the alcohol as well.

The more you use the stones the less you will clean them with alcohol or anything else, at least that is what I and EP have done. The only way we clean them anymore is by dressing them, and by far the best way to do that is loose abrasive on a flat surface and takes about 10 seconds. Unless you are sharpening professionally these stones will probably last the rest of your life. At the rate EP is going their 4k should sharpen well over 75,000 knives. Their 650 is wearing the fastest and at this rate it should sharpen around 15,000 knives even though they are overdressing them. With better care, it should last 3 or 4 times longer.

Keeping the stones wet while using them and a rinse with finger scrub after each use will go a long way in keeping them clean. Don't worry about a little color, it doesn't matter, they still cut the same.
 
I'm also very generous with the alcohol and I really lean into it with a shop towel. I don't use a single layer of towel - I wad it up and saturate it with alcohol. I also move to a clean section once it gets dirty. So I'll do a few passes, rotate the paper towel wad, a few more passes, and keep doing this until the towel is no longer getting dirty. It seems like a clean section of paper towel works better.

Thank you very much for that.
I've been a bit phobic to use paper towels on the oil stones because of the fibers left behind.
Micro fiber towels solves that.

For water stones it will be absolutely no problem because I can rinse off the paper under the faucet.
I'll try it.
Thanks again.
 
That's quite a claim. I wonder if @ToddS would work with you to figure out what's going on.
I have not tried the finer SGs but I do know for sure the 4,000 Shapton Glass is a phenomenal performer producing hair whittling edges in the medium hard carbides with no stropping at all.
I couldn't be happier with that (those) stones.
 
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