Edge Pro Matrix resin bond diamond stones

[Ilikesharpstuff]

I haven't posted on the forum for a long time. I just picked up a complete set of the DM Stones directly from Edge Pro. I just finished reading the whole thread from page 1 lol. One question I have is about developing a burr with the DM Stones, especially with the low grit stones. I've been sharpening for a long time with different systems and that's the only way I know when I've reached the apex from heel to tip. I then move to the next grit up and repeat with lighter and less strokes as I progress to final stropping. So what do you guys recommend?

Not sure exactly what your question is....are you asking whether you should still develop a burr with each grit before moving to the next one? I create a burr with each grit and then take a couple swipes to mostly remove it before moving on to the next. Some argue that you can save steel/extend the life of your blade by not fully apexing the edge (but getting really close) with your coarsest stone/stones but as someone who has never sharpened a knife so much it became unusable or even drastically changed shape I don't worry about this too much.

 

[Dutch87]

I haven't posted on the forum for a long time. I just picked up a complete set of the DM Stones directly from Edge Pro. I just finished reading the whole thread from page 1 lol. One question I have is about developing a burr with the DM Stones, especially with the low grit stones. I've been sharpening for a long time with different systems and that's the only way I know when I've reached the apex from heel to tip. I then move to the next grit up and repeat with lighter and less strokes as I progress to final stropping. So what do you guys recommend?

It sounds like you understand what to do. Once you've apexed your edge, you only need as many strokes with the higher grits as it takes to remove the previous stone's scratches. The Matrix stones do this very well, so by the time you get to the 2k and 4k, you'll probably be doing only a handful of strokes per side.

I find that a bright colored marker, good light, and a jeweler's loupe help me to be sure when I've apexed when the steel doesn't turn a strong bur. Keep marking the blade and checking even after you move to a higher stone, because often the higher grit stone and marker can reveal little spots that were missed by the lower stone, but you weren't aware of it. It's very satisfying to mark up an entire edge, and then have your 2k stone remove all the ink in one pass because you got it FLAT.

 

[jsp]

Not sure exactly what your question is....are you asking whether you should still develop a burr with each grit before moving to the next one? I create a burr with each grit and then take a couple swipes to mostly remove it before moving on to the next. Some argue that you can save steel/extend the life of your blade by not fully apexing the edge (but getting really close) with your coarsest stone/stones but as someone who has never sharpened a knife so much it became unusable or even drastically changed shape I don't worry about this too much.

It was mentioned in this thread that one should sharpen to the apex but not develop a burr with the DM stones. Developing a burr is the only way I know I've reached the apex.

 

[jsp]

It sounds like you understand what to do. Once you've apexed your edge, you only need as many strokes with the higher grits as it takes to remove the previous stone's scratches. The Matrix stones do this very well, so by the time you get to the 2k and 4k, you'll probably be doing only a handful of strokes per side.

I find that a bright colored marker, good light, and a jeweler's loupe help me to be sure when I've apexed when the steel doesn't turn a strong bur. Keep marking the blade and checking even after you move to a higher stone, because often the higher grit stone and marker can reveal little spots that were missed by the lower stone, but you weren't aware of it. It's very satisfying to mark up an entire edge, and then have your 2k stone remove all the ink in one pass because you got it FLAT.

I have to admit, I don't use a Sharpie to check my angles. I only use my naked eye to look for the burr and by feeling for it. I also stopped using a light loupe because I didn't want to get too anal about it. Maybe I need to revisit this and go back to it.

 

[David Richardson]

I would not apex with the course stone (80 grit?). I get close to apexing but try to not get deep scratches in my edge that are hard to remove. It's not the end of the world if you apex with the 80 grit, but I think you get a cleaner edge and finish faster do not apex until above 250. My goal is to not apex until I get to the 650 with my older stones - if I recall they are now 450 and 950.

 

[Dutch87]

I would not apex with the course stone (80 grit?). I get close to apexing but try to not get deep scratches in my edge that are hard to remove. It's not the end of the world if you apex with the 80 grit, but I think you get a cleaner edge and finish faster do not apex until above 250. My goal is to not apex until I get to the 650 with my older stones - if I recall they are now 450 and 950.

It's not as if the entire blade apexes at the same time. In my experience, usually the belly apexes first and the heel last.

I found the matrix 80 stone to be extremely aggressive, and indeed to scratch deep. I stopped using it. Maybe this is where this "don't apex coarse" thinking comes from; I've never heard that before.

Fwiw, I have Venev diamond resin stones in 80, 100, 150 and they don't feel anywhere near as rough as my Matrix 80 does. Maybe mine is special.

 

[jsp]

It's not as if the entire blade apexes at the same time. In my experience, usually the belly apexes first and the heel last.

I found the matrix 80 stone to be extremely aggressive, and indeed to scratch deep. I stopped using it. Maybe this is where this "don't apex coarse" thinking comes from; I've never heard that before.

Fwiw, I have Venev diamond resin stones in 80, 100, 150 and they don't feel anywhere near as rough as my Matrix 80 does. Maybe mine is special.

Yes, the belly/mid area usually apexes first, followed by the heel and tip. My first time sharpening with the DM stones, I tried edge-trailing strokes with the 80 grit to reprofile a 3.5" folder but it was taking too long to develop a burr. I went back to alternating edge-leading and edge-trailing strokes until it developed a burr. After that, I would flip the knife over and do one or two light edge-trailing strokes to break the burr off and continue alternating edge-leading and edge-trailing strokes repeating the process until it developed a burr from heel to tip. After that, I would do only edge-trailing strokes for 10-12 strokes on each side and progress to the higher grit stones only doing edge-trailing passes, 10-12 strokes per side.

 

[David Richardson]

It's not as if the entire blade apexes at the same time. In my experience, usually the belly apexes first and the heel last.

I found the matrix 80 stone to be extremely aggressive, and indeed to scratch deep. I stopped using it. Maybe this is where this "don't apex coarse" thinking comes from; I've never heard that before.

Fwiw, I have Venev diamond resin stones in 80, 100, 150 and they don't feel anywhere near as rough as my Matrix 80 does. Maybe mine is special.

This is completely dependent on how you sharpen. On the EP you usually have less control, but yes, one area of the blade will likely apex later than another. I try to compensate with blade positioning, but with a curved blade there are trade-offs and it's not going to be perfect.

 

[Wowbagger]

I have to admit, I don't use a Sharpie to check my angles. I only use my naked eye to look for the burr and by feeling for it.

I get tired of the ink coming off into the pores of my stones (the fine ones) .
Sharpy ink, in this application is kind of thickish . Personally I cut back on the ink by just putting "ticks" every half inch or 10mm or so down the edge.
One other option is machinist's dye; this tends to be slightly thinner . I put it in nail polish bottles I buy empty on the big river. I have a few stashed around the shops (work and home) .

I also stopped using a light loupe because I didn't want to get too anal about it. Maybe I need to revisit this and go back to it.

As I state in my signature : Good enough is good enough .
but Better "too anal" is Better .
Up to you.
I can sharpen stuff (especially more basic blades like slip joints , box knives , inexpensive kitchen knives ) freehand , without sharpy or lots of light (though I cheat with a jeweller's visor of not too high power Mag 5) and get your basic arm hair shaver .

. . . however . . . and especially for high alloy tool steel (and high alloy stainless on the rare occasion when I feel like whorerlng in that disreputable part of town)
LOTS OF LIGHT on the bench and on the visor
Visor mag 10
A touch of well placed dye
My beloved Edge Pro Apex
The ever so slightest bur reflection of something that is almost not there NOTHING ONE COULD EVER FEEL .
and oooooohhhhh I don't know . . . two swipes per side on the odd denim strop that visits annually with some super fine stropping medium
then two swipes per side on a hard leather finish side strop that , one mad , frivolous night , I introduced to a bottle of 50,000 diamond . . .
WELLLL
THAT IS BETTER !
call me obsessive
I'm one grinning obsessive .

PS : sharpening my good stuff (and come to think about it my box knife blades ) as I do . . . carefully and to a absolute minimum necessary . . . mostly on very fine grits . . . . I have to marvel and giggle to think people actually wear out blades just from edge touch ups . I can't imagine ; heck I use the same box knife blade for YEARS ! And then only wind of retiring it because I have found a higher alloy box knife blade or buy an etched one .
( Unboxing machines is part of my weekly tasks at work )

Edit to add " Visor Mag 10 for Better sharpening " .

 

[jsp]

Does anyone know if the DM Stones are available in 1/2" x 6" in all the grit ranges to sharpen Karambits/recurves?

 

[Dutch87]

Does anyone know if the DM Stones are available in 1/2" x 6" in all the grit ranges to sharpen Karambits/recurves?

I've never heard of half inch wide Matrix stones, but I'd love it if they were available.

I can recommend Venev Ursa 1/2” diamond resin stones; I've used those a lot on small blades.

Also, Gritomatic just restocked the Hapstone 1/2” CBN hybrid stones; right after I got them in from the Ukraine.

I've also used Venev Orion curved diamond plated stones to sharpen a few recurves to a mirror finish.

 

[jjg6319]

D Diemaker

Does anyone know if the DM Stones are available in 1/2" x 6" in all the grit ranges to sharpen Karambits/recurves?

 

[jsp]

I've never heard of half inch wide Matrix stones, but I'd love it if they were available.

I can recommend Venev Ursa 1/2” diamond resin stones; I've used those a lot on small blades.

Also, Gritomatic just restocked the Hapstone 1/2” CBN hybrid stones; right after I got them in from the Ukraine.

I've also used Venev Orion curved diamond plated stones to sharpen a few recurves to a mirror finish.

Thanks. I'll look into these. I've actually stopped buying recurve knives for the fact that they're harder to sharpen.

 

[Diemaker]

D Diemaker

Does anyone know if the DM Stones are available in 1/2" x 6" in all the grit ranges to sharpen Karambits/recurves?

I am making some right now as a sprint run, if you will. I made a prototype mold that makes 1 each 1"x6" stones with a 3", 6", 9", and 12" radiused resin surface for recurves. Edge Pro isn't interested in these so they are letting me make them with my name on them to test acceptance. I have two 80-micron and a 40-micron set as well as some hard polymer strop sets, with more polymer sets on the way. The problems with these stones is that we expect dressing the resin bond diamond stones will be a PITA and convincing you guys that using strops to sharpen with is viable, going as coarse as 40-micron emulsion and perhaps even 80-micron. Lots to go through so let's start with some photos.





3" on the right and 12" on the left. The Overall thickness is .25" like the Matrix stones. This works for the strops but doesn't give enough life for the 3" stones, woops. I was only thinking of them being strops when I created the CAD model and mold, it was only later that I thought of making some stones from the molds.

The reason to sharpen with strops instead of stones when using radiused stones is you only need one or two "stones" to do everything but reprofile, you don't ever have to dress them, they hold their shape and thickness very, very well, and you don't need to compensate since the strops are all the same thickness bar any wear. You do have to buy the emulsions but that shouldn't be too much more $$ than stones in the long run.

When sharpening with these polymer strops I need to use around 3 times as many strokes as my Matrix stones, but other than that, they work perfectly fine. The resins' hardness is between veg tanned cow leather and the Matrix stones. It is hard enough that any convexing is minimal, say .002" on a .04" wide bevel, but soft enough that it doesn't chip Kyocera black ceramic, which is the chippyest blade I have ever sharpened. It is also very wear resistant, and so far, I have been using one strop for 5 to 40 micron emulsions and a second strop just for the 1-micron emulsions without issues. I clean between emulsions with a small piece of paper towel soaked in alcohol. Stroppy Stuff works very well with these strops and Cody has been using a chromium oxide past with great results. I have used a water-based emulsion with good results, as long as you keep it wet, and have been testing mineral oil based emulsions that I think work best. One drop is all I need and may last up to 100 strokes or more.

Speaking of which, I have been making these strops in 1"x 4" and 2"x 6" for some time, and now 2"x 8" bench stones. Edge Pro has a batch of 1"x 6" strops in stock, but they aren't on their website yet so you would have to call.

Time to get to work.

 

[jsp]

Awesome! I'll be looking out for these when you get them done. Thanks for the reply.

 

[NotSoSharpBob]

I hope this is the right place to post this

I gouged my brand new Edge Pro Diamond Matrix Stone. Can it be fixed?​

I'm pretty sure I did this by pushing into a freshly created burr. I assumed diamond stone would be harder than the cheap knife steel burr I was sharpening. Am I correct this was my own inexperienced fault? I guess the right way to prevent it is to always hit the burr from the back side.

Suggestions on fixing the stone? I tried the 240 grit sandpaper on a piece of glass and it is better now but I didn't want to get too aggressive with the approach before I got suggestions here. It's a 1700 grit if that matters.

Thanks D Diemaker or anybody else with experience and more brains than me.

 

[jjg6319]

If you watch D Diemaker videos he suggests light trailing edge strokes and I would think to avoid a situation like you encountered. He recommends 10 light strokes for a 3" long blade. The diamond matrix stones are great for the high hardness steels like Maxamet, Rex 121, ZDP 189, etc. I went back a reread some of the previous posts in this thread from diemaker and you might find more information in them on how to use these stones, if you have the time.

I expect the "cheap knife" is somewhat lower hardness and you could use just normal EP stones. I would not use the diamond matrix stones for soft steels.

D Diemaker will have to comment on how to repair it.

 

[bmo419]

I hope this is the right place to post this

I gouged my brand new Edge Pro Diamond Matrix Stone. Can it be fixed?​

I'm pretty sure I did this by pushing into a freshly created burr. I assumed diamond stone would be harder than the cheap knife steel burr I was sharpening. Am I correct this was my own inexperienced fault? I guess the right way to prevent it is to always hit the burr from the back side.

Suggestions on fixing the stone? I tried the 240 grit sandpaper on a piece of glass and it is better now but I didn't want to get too aggressive with the approach before I got suggestions here. It's a 1700 grit if that matters.

Thanks D Diemaker or anybody else with experience and more brains than me.

Unfortunate, but yeah what jjg said. Diamonds are indeed harder than whatever steel is out there, but the resin that makes up the majority of these types of stones is not. The diamonds in these stones are just interspersed in a resin matrix, think chocolate chips (the diamonds) in a chocolate chip cookie (the rest of the cookie=the resin). So they are much softer compared to an electroplated diamond plate, for example. If you have a burr, do some edge trailing passes first to flip the burr over and then you can do some edge leading strokes. Though I know diemaker doesn't recommend edge leading on these stones in particular for the reasons you found out.

 

[Diemaker]

I hope this is the right place to post this

I gouged my brand new Edge Pro Diamond Matrix Stone. Can it be fixed?​

I'm pretty sure I did this by pushing into a freshly created burr. I assumed diamond stone would be harder than the cheap knife steel burr I was sharpening. Am I correct this was my own inexperienced fault? I guess the right way to prevent it is to always hit the burr from the back side.

Suggestions on fixing the stone? I tried the 240 grit sandpaper on a piece of glass and it is better now but I didn't want to get too aggressive with the approach before I got suggestions here. It's a 1700 grit if that matters.

Thanks D Diemaker or anybody else with experience and more brains than me.

Yeah, the resin is softer and with the finer grits you can carve them, with the coarser grits the bigger diamond crystals protect the resin. Either way it's not good on your knife either. Personally I would just use the stone, after dressing it with loose abrasive. Sandpaper doesn't work to dress with, you can only get about 20% towards a proper dress with it.

Edge trailing would prevent this from happening, but the reason I use edge trailing is for a keener apex, easier on the diamonds, and I can go longer between dressings. If you are getting burrs with edge trailing strokes with this stone either the steel is too soft or you haven't cleaned up the apex yet. After you have refined the apex with that stone the biggest burrs I have ever seen are well less than .001" long, but generally nothing.

The idea of using edge leading strokes to remove the burr sends shivers down my spine, the damage it does to the apex ripping it off can be bad.

 

[NotSoSharpBob]

Thank you all for the responses. I'm a big boy, I was doing good practicing with cheap knives so as not to ruin any of my good ones and there I go ruining my good stone! I understand the resin recipe now, I gouged the resin and not the diamond. Valuable lesson. Now back to the workbench. I have never dressed a stone before so I will YouTube that.

Thanks again

Bob