Columbia Gorge Stoneworks Resin Bond Diamond Stones

Diemaker

Knifemaker / Craftsman / Service Provider
Joined
Apr 28, 2017
Messages
944
I am starting this thread for tech support of my bench stones, just like I did for the Matrix stones. I am linking to it on the Technical Support page of my website hoping most tech help and general questions can be answered here. Since I am a one person shop it's hard to impossible to answer the phone while molding stones or running my CNC mill. My new bench stones use the same diamond and resin bond as the Matix stones and the same aluminum alloy for the mounts. I have modified 3 of the grits a small amount so these stones have even 50% reductions in the abrasive size as you drop down in grits. All advice I have given regarding the use and care of the Matrix stones applies to my bench stones and vise versa. My philosophy is to make the best products from as much American made materials as feasible with the least waste. All the work and expense go into the stones or other products I will be making and nothing else, so the packaging is pretty minimal. Hopefully this will be accepted, if not I will adjust accordingly.

I still haven't settled on a name for them and would really like help with this, please! So far I am thinking Pirannahs but I am open to suggestions.
 
Out of curiosity, what is the grit distribution like in these? In other words, for a hone for example with a target size of 5 micron grit, what amount of particles of other sizes are in the mix?
 
I get Particle Size Distribution charts with all of my diamond powder but am not 100% sure how to read all of it. For the last batch of 5 micron powder I got the average size is 5.869, median or 50% above and below size is 5.796, average surface area size is 5.184, mode or size of most frequency is 6.452, d10 is 3.493, d90 is 8.426. This batch of 5 micron has a bit wider differential than normal and the coarser grits are also tighter than the 5 micron, the finer grits have a higher percentage size swing since the mean is so small. A 2-3 micron size swing has a bigger effect with 5 micron powder than 80 micron powder. I have tried tighter controlled size powder but did not see any difference when viewing the sharpened bevel under the microscope. Since my bond is on the soft side and it's resin to begin with it really seems to average how the diamonds cut. The harder the bond the more pronounced the scratches from stray larger crystals, and there always are some. While we can put numbers on the abrasives we really can't on the bond, which is just as important, so eventually you just need to try the stones out to see how they cut. Another huge variable is how much diamond is in your stones and how much of other abrasives are in there.
 
I get Particle Size Distribution charts with all of my diamond powder but am not 100% sure how to read all of it. For the last batch of 5 micron powder I got the average size is 5.869, median or 50% above and below size is 5.796, average surface area size is 5.184, mode or size of most frequency is 6.452, d10 is 3.493, d90 is 8.426. This batch of 5 micron has a bit wider differential than normal and the coarser grits are also tighter than the 5 micron, the finer grits have a higher percentage size swing since the mean is so small. A 2-3 micron size swing has a bigger effect with 5 micron powder than 80 micron powder. I have tried tighter controlled size powder but did not see any difference when viewing the sharpened bevel under the microscope. Since my bond is on the soft side and it's resin to begin with it really seems to average how the diamonds cut. The harder the bond the more pronounced the scratches from stray larger crystals, and there always are some. While we can put numbers on the abrasives we really can't on the bond, which is just as important, so eventually you just need to try the stones out to see how they cut. Another huge variable is how much diamond is in your stones and how much of other abrasives are in there.
With AlOx and Silicon Carbide a lot of manufacturers seem to use d50, but it varies so much who quoted which values. With those "softer" abrasives, d50 use makes sense.

With Diamond or CBN, the d90 value would be more important to know because those stray particles can show extreme scratches. Only problem is, if you quote d90, then people seem to think your stones are not as "good" as other brands...which is not true. Your stones are great. For the finer grit hones, it is great that your bond is on the softer side to compensate for the d90 particles.

For your 80 grit Matrix stone, I have found that it might be better to have a much harder bond? Especially because this is the "work horse" when it comes to setting a new bevel or removing chips. I've found that with my matrix stones, the 80 wears quite fast so I end up using diamond plates to "save" the 80 grit stone. Yes - doing edge trailing strokes like in your videos is great and the stones will last longer, but if you have a lot of bevel setting to do edge leading and trailing is what will be done inevitably just to get the job done. This seems to be hard on the 80 grit. Any chance you can make the bond harder for the 80 grit?
 
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What type of resin are the stones made from? Can you use them with oil or synthetic lapping fluid?
I want to keep the exact resin to myself but you can use oil with them, preferably simple mineral oil. I know some solvents will attack the resin but I would think synthetic lapping fluid would be ok, but no guarantees. I find water with a hint of dish soap is best. The only downside is it evaporates, but it washes the swarf off way better than oil and makes far less of a mess.

With AlOx and Silicon Carbide a lot of manufacturers seem to use d50, but it varies so much who quoted which values. With those "softer" abrasives, d50 use makes sense.

With Diamond or CBN, the d90 value would be more important to know because those stray particles can show extreme scratches. Only problem is, if you quote d90, then people seem to think your stones are not as "good" as other brands...which is not true. Your stones are great. For the finer grit hones, it is great that your bond is on the softer side to compensate for the d90 particles.

For your 80 grit Matrix stone, I have found that it might be better to have a much harder bond? Especially because this is the "work horse" when it comes to setting a new bevel or removing chips. I've found that with my matrix stones, the 80 wears quite fast so I end up using diamond plates to "save" the 80 grit stone. Yes - doing edge trailing strokes like in your videos is great and the stones will last longer, but if you have a lot of bevel setting to do edge leading and trailing is what will be done inevitably just to get the job done. This seems to be hard on the 80 grit. Any chance you can make the bond harder for the 80 grit?
D50 is the mean size, or average, so if you are going to show anything that would be it. I understand that too much information can look bad unless you understand what it really means, which is generally quite complicated. The bond is just as important as the abrasive and mine does a good job of averaging the scratches, or so my microscope tells me.

Generally, when someone is seeing excessive wear with their 80 grit stone it is from swarf, which acts just like the loose abrasive used to dress the stone, it simply erodes the resin away, or being too aggressive on too small of a bevel. A good photo may shed light on what is happening. Have you measured how much your stone has worn?

Edge trailing strokes are only important if you have reached the apex, and with the 80 it is more for the safety of the knife than the stone. This coarse of a stone will really tear up the apex requiring a lot more work with the next grit to clean up the damage to the apex from the last grit. If I have not reached the apex I use back and forth strokes.

I agree a harder resin for the 80 would have benefits, but it would also have drawbacks. The harder resin would help the stone be more aggressive but it would also cause more damage to the apex. It would be better at reprofiling but not as good for maintenance sharpening, IMO so far. While I have some things in mind and would like to test them further the harder resins use a totally different process vs what I am doing now. Of course, the most interesting harder resins are much harder to process than the more mainstream ones, this rabbit hole turns out to be a cavern!
 
Good to know you're already considering a harder resin for the workhorse 80 grit!

It won't matter for maintenance because the 80 it not really a maintenance stone in my opinion. More of a re-profiling and bevel setter.
 
Would 160 micron stone of yours to my progression of kme stones be ok? Or would I be better off using the whole progression of your stones?
 
I think you would be happier with the whole progression vs just the 160. I think you will see better results comparing my finer stones to your KMEs vs the 160 to them.
 
Would 160 micron stone of yours to my progression of kme stones be ok? Or would I be better off using the whole progression of your stones?
Eman816, what are you thinking regarding inserting Diemaker's 160 into KME's diamond progression? What are you hoping to accomplish?
 
Just a diff coarse stone instead of the gold series 100grit
:thumbsup:- KME's 140 plated diamond is at least close to Diemaker's 160 grit, though I would love to try the set some day. Diemaker's 4 inch stones are less costly and more "monthly budget friendly" then 6", and I have three after market KME stone holders (expands KME stone versatility along with KME's axe sharpener)...
I have concluded that for all the knives I have sharpened with KME, 10 inches and down, 4 inch stones are perfectly serviceable.
Sharpmaker rods are great for serrations and recurves; SIC is least expensive way for removing stock on all lower Vanadium steels; natural stones are perfect for the kids knives; KME Axe sharpener adds versatility: 3D Printed accessories interesting, and increases functionality.
Funny how side ways some knowledge gets understood...
 
D Diemaker
I’m a fan of Spyderco PM knives (k390, m390, 20cv, etc) and I finally need sharpening stones for these super steels.

I freehand sharpen. I think I could make your CGSW stones in 6x2” size work, but I could find no info or examples of people freehand sharpening with these or other sizes. How do your stones work for freeehand?

Grit progression - I have an office job, so my knives see little daily use and need infrequent sharpening. Could I start with just the 40, 20, and 10 micron stones and then strop w/ 1-0.5m spray? Could I even start w/ 2 of those stones? (I know you’d prefer to sell sets, but appreciate your honest opinion as I’m just getting started w/ diamond.)

Flat plate - for dressing the stones, what’s a good, but least expensive option for the plate? Eg your video showed a sample Cambria tile (quartz?) vs glass (type?) vs DMT coarse plate?

Thank you in advance for your input, very helpful before buying. And woot for the gorge, I visit Rowena and Hood River often.
 
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:thumbsup:- KME's 140 plated diamond is at least close to Diemaker's 160 grit, though I would love to try the set some day. Diemaker's 4 inch stones are less costly and more "monthly budget friendly" then 6", and I have three after market KME stone holders (expands KME stone versatility along with KME's axe sharpener)...
I have concluded that for all the knives I have sharpened with KME, 10 inches and down, 4 inch stones are perfectly serviceable.
Sharpmaker rods are great for serrations and recurves; SIC is least expensive way for removing stock on all lower Vanadium steels; natural stones are perfect for the kids knives; KME Axe sharpener adds versatility: 3D Printed accessories interesting, and increases functionality.
Funny how side ways some knowledge gets understood...
I'd say the KME 140 is closer to the CGSW 80. Diemaker's stones are rated in microns, which is not the same thing as KME's grit rating. The KME 100 grit stone is probably equivalent to the CGSW 160.
 
BearShark44, my stones are designed specifically for freehand so they do work fine. Keep in mind they are a "softer" stone so be careful with your angles to avoid carving into them, like any softer stone. I would say the 40m would be fine for taking out very small chips so you may not need it and you may want around 3-5 micron diamond to strop with after the 10m, 1 micron would be too big of a jump. I understand not needing all the stones in a full set but do advise getting them in even order. 20 and 10 is fine, I wouldn't go 40 and 10 or 20 and 5. You can sort of get away with those jumps but you better hold your angles perfectly to get the scratches from the previous stone to clean up. Watch out for a foil burr with diamond loaded strops on most steels, you will probably want to finish with bare leather or such to remove it.

I do suggest edge trailing passes with my stones but that has far more to do with the diamond abrasives than anything else, and I feel even more strongly about this for plated diamonds.

The dressing plate just needs to be flat and fairly wear resistant. A piece of glass, granite, or porcelain tile will work fine. Don't use diamond plates, they are only for non-diamond stones and the cutting action is different anyway being bonded abrasive. You want loose abrasive between the two surfaces, it works very differently than bonded abrasive. You won't hurt, or help much, the resin bond diamond stones but will take the edge off of your plated diamonds. The loose abrasives won't wear the diamonds but do wear the resin around them exposing them, which is exactly what you want.

What brings you to Rowena? It certainly is off the beaten path.
 
BearShark44, my stones are designed specifically for freehand so they do work fine. Keep in mind they are a "softer" stone so be careful with your angles to avoid carving into them, like any softer stone. I would say the 40m would be fine for taking out very small chips so you may not need it and you may want around 3-5 micron diamond to strop with after the 10m, 1 micron would be too big of a jump. I understand not needing all the stones in a full set but do advise getting them in even order. 20 and 10 is fine, I wouldn't go 40 and 10 or 20 and 5. You can sort of get away with those jumps but you better hold your angles perfectly to get the scratches from the previous stone to clean up. Watch out for a foil burr with diamond loaded strops on most steels, you will probably want to finish with bare leather or such to remove it.

I do suggest edge trailing passes with my stones but that has far more to do with the diamond abrasives than anything else, and I feel even more strongly about this for plated diamonds.

The dressing plate just needs to be flat and fairly wear resistant. A piece of glass, granite, or porcelain tile will work fine. Don't use diamond plates, they are only for non-diamond stones and the cutting action is different anyway being bonded abrasive. You want loose abrasive between the two surfaces, it works very differently than bonded abrasive. You won't hurt, or help much, the resin bond diamond stones but will take the edge off of your plated diamonds. The loose abrasives won't wear the diamonds but do wear the resin around them exposing them, which is exactly what you want.

What brings you to Rowena? It certainly is off the beaten path.
Thanks D Diemaker for the advice and context. It'd be helpful if you or one of the online sharpening influencers could post a video of freehand sharpening with only edge trailing strokes on your 6x2 or similar stones. I'm thinking it extends the time, which is already longer on bonded diamond than plated, but that's okay. More just good to see the tempo. I visit Rowena area for family, windsurfing, hiking, and such.

[Post edit 6/21/22] D Diemaker - just FYI I found a video of sharpening influencer Jef Jewel freehand sharpening on matrix stone. LINK. Helpful and thank you for your response below to this question on trailing/leading stroke direction. Very helpful. Time to buy the stones and get started finally.
 
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I can freehand but don't now that I have a good guided sharpener, there just is no comparing the two if you want to maintain a consistent angle. Rikki shows how he freehands with an emphasis on the trailing stroke and varying pressure so I figure he is a good reference on how it should be done with diamond stones. Here is his YouTube channel https://www.youtube.com/c/Burrfection. Keep in mind if you can keep a perfectly consistent angle you only need 3-4 strokes per inch of blade with each grit before progressing to the next, with my stones. I have found any more than this does nothing to improve the edge. This is for the progression after you have set the bevel.

Please understand there are no hard and fast rules, there are only suggestions and food for thought ideas depending on the details of what you are doing. When roughing I sharpen in both directions, I only worry about edge trailing once I am trying to refine the apex. How important this is depends on the material being sharpened, the more it likes to chip the more important it is to use edge trailing. How hard the stone is makes a difference too.
 
Despite having a vast selection of stones, I've pretty much abandoned everything except your stones that I use on my EdgePro. Currently I'm wanting some triangular stones, so I checked your web page out first, but found nothing.

So I guess my question is, are triangular diamond matrix stones a bad idea? If they're a good idea, then I'd really like to get a set.
 
I don't think there ever will be triangular Matrix stones since any resin used isn't that "rugged" and wouldn't hold up that well to the extreme point loading, assuming you want to keep those sharp corners on the stones.

What are you looking to do with triangular stones? So they need to be that exact shape?
 
My intention is to use the triangles to work on some serrated blades, on the bevel side.
If you have other suggestions what might work well for me, I'm all ears.
 
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