DMT Sharpening Hone question

630skirmish

630skirmish

Joined
Nov 30, 2013
Messages
384
I have these stones right here excluding the extra course, so what I have is the

http://www.sharpeningsupplies.com/DM...-Kit-P405.aspx
Course-320 Grit
Fine-600 Grit
Extra Fine-1200 Grit

The jump from fine to extra fine seems to be way too much, not really sure why there isn't a 900 grit between fine and extra fine.
Does anybody know of a good diamond sharpening stone 8x3 that is about 800 to 900 grit?

I would be open to suggestions on using completely different stones as well, and if so is it ok to mix it up?
 
I've found the fine (red) and ultra fine (green) combo to be perfectly adequate; I can get scary edges just with those. I have noted, though, that D2 seems to cut better without going to the ultra fine; a slightly coarser edge just seems to cut better with that steel. The coarse grit is handy for re-profiling an edge but I rarely need to use it. I've used my DMT bench hones for a couple of decades without seeing any reduction in their cutting efficiency. From time to time I wipe them down with BreakFree to lift off the swarf (left overnight seems to work best).
 
630skirmish said:
The jump from fine to extra fine seems to be way too much, not really sure why there isn't a 900 grit between fine and extra fine.
Does anybody know of a good diamond sharpening stone 8x3 that is about 800 to 900 grit?
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That's a nice setup!

I have the C and the EF. I do not have the F. I VERY frequently jump straight from the C to the EF. The EF removes the scratch pattern from the C completely. It does so much faster than you might expect. So I don't even need the F. I'm not sure what you're experiencing, but you should very easily be able to remove the scratch pattern of the F using the EF.

The EF yields a really nice edge for kitchen work.

Brian.
 
Diamond is about ~ 8X-9X as hard as the matrix steel in most knives, and 2.5X-3X as hard as the hardest carbides in knives (vanadium carbides, chromium carbides account for most of those). Don't be swayed too much by the published 'grit' ratings' apparent 'gap' in size, as diamond will still work very fast in cleaning up scratch patterns at even small/very small grit sizes. The 'jump' from DMT's Fine to EF (600 to 1200) really isn't much of a jump at all, for diamond. It'll cut any steel like butter, regardless of grit size.

Not that there's really a need for it in that sequence, but if you REALLY want to find something 'in between' DMT's Fine & EF, you might look at EZE-LAP's '1200' grit hones; I think they label it a 'Super Fine', color-coded BLUE in their grit scheme. They use a polycrystalline diamond on their hones, which makes them perform effectively 'coarser' as compared to similar/same rated grit from DMT. The polycrystalline diamond (clumps/agglomerations of smaller grit at the rated size) work for a while like 'bigger' grit, meaning they'll remove metal more quickly initially, then settle into a finer-grit performance as the hone wears with use over time, and the agglomerations or clumps break down into individual crystals. I have one of their pocket hones in a double-sided 400/1200 combination (looks similar to DMT's DiaFold hone), and I've noticed the '1200' side is performing at a much coarser level than DMT's '1200'. It might even compete with DMT's 'Fine', in terms of metal removal and the scratch pattern left. I'd personally not bother including it between DMT's Fine & EF, as it'll effectively just remove more steel needlessly, without really adding much in scratch pattern refinement from the DMT 'Fine'.


David
 
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Obsessed with Edges said:
Diamond is about ~ 8X-9X as hard as the matrix steel in most knives, and 2.5X-3X as hard as the hardest carbides in knives (vanadium carbides, chromium carbides account for most of those). Don't be swayed too much by the published 'grit' ratings' apparent 'gap' in size, as diamond will still work very fast in cleaning up scratch patterns at even small/very small grit sizes. The 'jump' from DMT's Fine to EF (600 to 1200) really isn't much of a jump at all, for diamond. It'll cut any steel like butter, regardless of grit size.

Not that there's really a need for it in that sequence, but if you REALLY want to find something 'in between' DMT's Fine & EF, you might look at EZE-LAP's '1200' grit hones; I think they label it a 'Super Fine', color-coded BLUE in their grit scheme. They use a polycrystalline diamond on their hones, which makes them perform effectively 'coarser' as compared to similar/same rated grit from DMT. The polycrystalline diamond (clumps/agglomerations of smaller grit at the rated size) work for a while like 'bigger' grit, meaning they'll remove metal more quickly initially, then settle into a finer-grit performance as the hone wears with use over time, and the agglomerations or clumps break down into individual crystals. I have one of their pocket hones in a double-sided 400/1200 combination (looks similar to DMT's DiaFold hone), and I've noticed the '1200' side is performing at a much coarser level than DMT's '1200'. It might even compete with DMT's 'Fine', in terms of metal removal and the scratch pattern left. I'd personally not bother including it between DMT's Fine & EF, as it'll effectively just remove more steel needlessly, without really adding much in scratch pattern refinement from the DMT 'Fine'.


David
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I don't profess to have Dave's experience but in my experience unless you want to mess with a non diamond stone there isn't much in between and you don't really need it anyway. I have all the dmt, then got almost all the shapton glass up to 6000, then bought the smiths, the atoma 1200, now I have promised myself I will stop.:rolleyes: Have fun, good luck, get sharp!!! Russ
 
Is there a specific sharpening problem you are having that led you to believe you might need a stone between the fine and extra fine?
 
Just to add to the other great comments here, I don't think there is a need to bridge that gap at all.
 
I go from the 600 to the 1200 no problem and then to a 4 k from there, sometimes I go as high as 8k but again it is from the 4k to the 8k. you may be using too much pressure on the 600 and 1200, that will cause the scratches left to be deeper and more visible. if it is the knife seemingly duller you aren't polishing the apex.
 
fsatsil said:
Is there a specific sharpening problem you are having that led you to believe you might need a stone between the fine and extra fine?
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Sharpening on the 320 and 600 grit feels great but when I go to the extra find it feels like there are rocks and nics everywhere. Not sure of this is the stone but I have gotten a second extra fine and it's the same deal. Just sounds wrong when I sharpen like it's going over glass.
 
You are not giving the plate time to break in.

ALL diamond hones are very rough and gritty from the start, you must use them a fair amount before they settle into producing consistent results. Pushing hard or being forceful will not only damage the bevel of the tool being worked on but also damage the diamond plate, so avoid doing that.

Getting to know any sharpening tool takes time, no matter how skilled you are it takes a lot of practice with each individual stone to become proficient with it.
 
the finer you go the less grinding and more polishing you do hense the feel you are polishing the rough spots out.now continue honing.
 
630skirmish said:
Sharpening on the 320 and 600 grit feels great but when I go to the extra find it feels like there are rocks and nics everywhere. Not sure of this is the stone but I have gotten a second extra fine and it's the same deal. Just sounds wrong when I sharpen like it's going over glass.
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+1 to Jason's input, re: letting the EF hone 'break in'. More than likely, that's what's going on; it's normal.

Another possible contributor to the 'rough' feel when stepping between grits: sometimes, as you refine on finer-grit hones, some of the burrs & other edge debris from coarser steps will come off the edge and leave some pieces on the hone, and will contribute to that 'gritty' feeling. As the scratch pattern becomes more refined, it usually smoothes out a bit (& helps to clean the rougher debris off the hone also). When most/all of the coarser scratches are replaced by finer ones, the feel should almost become 'buttery' on the finer hones (EF & EEF especially), with most steels.

Don't worry about it too much; just give the hones some time to break in. Sometimes that can be accelerated a bit by taking an expendable blade and just scrubbing some new bevels into it on the new hone. That's sometimes enough to knock off some/most of the rough bumps on new diamond hones.


David
 
Obsessed with Edges said:
+1 to Jason's input, re: letting the EF hone 'break in'. More than likely, that's what's going on; it's normal.

Another possible contributor to the 'rough' feel when stepping between grits: sometimes, as you refine on finer-grit hones, some of the burrs & other edge debris from coarser steps will come off the edge and leave some pieces on the hone, and will contribute to that 'gritty' feeling. As the scratch pattern becomes more refined, it usually smoothes out a bit (& helps to clean the rougher debris off the hone also). When most/all of the coarser scratches are replaced by finer ones, the feel should almost become 'buttery' on the finer hones (EF & EEF especially), with most steels.

Don't worry about it too much; just give the hones some time to break in. Sometimes that can be accelerated a bit by taking an expendable blade and just scrubbing some new bevels into it on the new hone. That's sometimes enough to knock off some/most of the rough bumps on new diamond hones.


David
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Thanks all for all the tips and pointers, very helpful. When I received the extra fine stone (which is the only stone from the set I have an issue with) I see little scratches on diamond layer. This was like this before sharpening and I cant feel it with my fingers. To those that have the extra fine, does yours have little scratches in the stone? If so is this the issue I am refering to and I should return this stone for a replacement or just keep sharpening and break in the stone.
 
630skirmish said:
Thanks all for all the tips and pointers, very helpful. When I received the extra fine stone (which is the only stone from the set I have an issue with) I see little scratches on diamond layer. This was like this before sharpening and I cant feel it with my fingers. To those that have the extra fine, does yours have little scratches in the stone? If so is this the issue I am refering to and I should return this stone for a replacement or just keep sharpening and break in the stone.
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That's normal and typical on diamond hones, and more visible on the finer ones in particular. The 'scratches' are just rub marks in the surface of the nickel substrate. So long as you're not actually feeling them (as if they were deep gouges), it's nothing to worry about. I don't think I've ever seen a diamond hone that didn't have some of those rub marks on the surface, for what it's worth; they still work just fine.


David
 
David (OWE) mostly said this, but I think it's worth saying a little more:

With fine stones, you're going to feel and hear every bit of debris that's sitting on the stone. If you have a blade that has grit on it, you're going to REALLY feel it on a fine stone. This grit could be metal or abrasive left over from a previous step. Or, as has been suggested, it could be just the rough parts of the diamonds breaking off.

No matter what it is, it's a good idea to wipe the blade down with a wet cloth *and* flush the stone with water and wipe it with your fingers to try to remove any debris that might be sitting on the stone. So flush the stone and wipe the blade several times during sharpening. You should get a nice smooth stroke once you get the "stuff" off of the stone and blade.

If it's just the diamonds breaking off, then it will take a few sharpening sessions, but that too will pass.

Brian.
 
^^I call those little bits of loose debris on the hones 'speed bumps'; that's what they feel like when the edge runs over them. The sound of it makes me cringe. :eek:

At times, I can feel bits of a known burr 'fold under' on the hone as it gets scrubbed off, and the edge then sort of trips over that bit of steel as it separates from the edge. When that happens, it means the edge is indeed being 'refined', and that's a good thing. ;)

As mentioned though, it's almost always a temporary thing (wipe down/clean the hones frequently & let them break in). So, no worries.


David
 
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bgentry said:
David (OWE) mostly said this, but I think it's worth saying a little more:

With fine stones, you're going to feel and hear every bit of debris that's sitting on the stone. If you have a blade that has grit on it, you're going to REALLY feel it on a fine stone. This grit could be metal or abrasive left over from a previous step. Or, as has been suggested, it could be just the rough parts of the diamonds breaking off.

No matter what it is, it's a good idea to wipe the blade down with a wet cloth *and* flush the stone with water and wipe it with your fingers to try to remove any debris that might be sitting on the stone. So flush the stone and wipe the blade several times during sharpening. You should get a nice smooth stroke once you get the "stuff" off of the stone and blade.

If it's just the diamonds breaking off, then it will take a few sharpening sessions, but that too will pass.

Brian.
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This is probably what I am hearing and feeling when sharpening. Thank you!
 
So After sharpening on all three, course, fine and extra fine I get a pretty good edge. Im not an expert but Im not a novice either, Ive sharpened a good amount of folding, fixed and kitchen knives and can get an edge that looks pretty good and cuts through phone book paper.

Still though, after sharpening on all three I feel the edge is still a bit course. Could just be my sharpening but is there another step I should take after wards to make it even sharper?
 
630skirmish said:
So After sharpening on all three, course, fine and extra fine I get a pretty good edge. Im not an expert but Im not a novice either, Ive sharpened a good amount of folding, fixed and kitchen knives and can get an edge that looks pretty good and cuts through phone book paper.

Still though, after sharpening on all three I feel the edge is still a bit course. Could just be my sharpening but is there another step I should take after wards to make it even sharper?
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'A bit coarse' is very subjective; hard to quantify and you'll get very different descriptions of it, depending whom you ask. But, if you want the edge somewhat finer-finished than it currently is, following with a medium ceramic like Spyderco's 'brown' and their Fine & UF hones could do it. OR, you could follow with stropping on wood with diamond compound at 6µ and smaller. There are LOTS of other ways to refine beyond the DMT EF hone, so these are just a couple possibilities. Other stropping compounds could be used as well, if the steel doesn't really need the diamond for refinement (like S30V and other vanadium carbide-heavy steels will). Simpler mainstream steels (anything from 1095, 420HC, 440A/C, 154CM, VG-10 and up through D2, for example) will respond well to aluminum oxide compounds like white rouge, Flitz/Simichrome polish, or Mother's Mag polish on firm/hard strops.

DMT also offers an EEF hone (8000 mesh/3µ), which will take the EF finish to (possibly) a hazy mirror. At that stage though, it's likely you could get it finer with many other less-expensive options, many of which involve stropping as mentioned above.


David
 
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