rbscebu
Girls call me Makaluod
I sometimes read things like 12k DMT in a post. What does DMT mean?
DMT?
- Thread starter rbscebu
- Start date
EclipseRedRing
I smell like a Christmas pudding
I think DMT is a maker of various sharpening and honing materials. I could be wrong though. DMT Diamond Stones for Sharpening and Honing - https://www.dmtonlinestore.com/
DMT is a manufacturer of diamond sharpening tools; based in Massachusetts USA.
I think 8k or 3µ is the finest they make; they make a 1.2k hone. Good stuff.
I think 8k or 3µ is the finest they make; they make a 1.2k hone. Good stuff.
@EclipseRedRing is right. A DMT 325 is a diamond plate used by lots of people for flattening water stones. If you're into pocket knives, the newer super steels are so hard that you need diamonds to do a good job sharpening them. I've heard of some guys using the 1.2k up to 8k for straights but I think they're probably a little better for knives.
timwcic
"Look what I found"
DMT, Diamond Machine Technology, good stuff
Good quality Diamond plates. Afaik, they don't go above 8k (3micron).
I hone primarily on them.
The XXC, XC and C make decent stone lapping plates. F and EF good for chip removal and beveling razors, 8k (EE) good for sharpening a razor to follow up with a finisher... never tried the 4k.
Not the biggest fan of them for knives personally, but they work. I just prefer naturals all the way for knives. Maybe diamonds or carbo for HEAVY stock removal... but rarely.
I hone primarily on them.
The XXC, XC and C make decent stone lapping plates. F and EF good for chip removal and beveling razors, 8k (EE) good for sharpening a razor to follow up with a finisher... never tried the 4k.
Not the biggest fan of them for knives personally, but they work. I just prefer naturals all the way for knives. Maybe diamonds or carbo for HEAVY stock removal... but rarely.
Slash McCoy
I freehand dog rockets
I just picked up a "Fine" DMT on sale from Home Depot the other day. I couldn't remember what grit the "Fine" was. Tried to set the bevel on a GD66 with it and got the chippiest edge I have ever made. I should have sharpened a few kitchen knives on it first. They do cut vicious quick, and they are a lot flatter than the cheap diamond plates you get at Harbor Freight. A bit small in my hand. I would guess this one is actually about 400 grit with a lot of proud diamonds. It would be great for sharpening a work knife but I won't let it near any of my razors anytime soon. I guess it was the "EF" I was thinking of when I bought it.
Ive seen many use DMT plates to flatten a whetstone....but I use wet dry sandpaper.
Also seen some use a DMT to raise a slurry on a stone....I can't figure how that works...
as I always felt there was a chance traces of the material from the DMT might transfer to
a high grit stone and spoil the results.....but many pros do it so I must be mistaken.
Also seen some use a DMT to raise a slurry on a stone....I can't figure how that works...
as I always felt there was a chance traces of the material from the DMT might transfer to
a high grit stone and spoil the results.....but many pros do it so I must be mistaken.
Fine is apparently 600 grit but they do seem to always have a few diamonds sticking up farther than you'd want them for a really smooth edge.
kelbro
Alfred Spatchcock
I believe they have an extra extra fine as well. Tan color code I believe. I don't have access to my hone box right now our I would confirm.
Yes, I have one. I like it well enough but prefer a Naniwa or Shapton at that grit.
My Extra Fine is well worn and makes a very good bevel setter.
I use the course for heavy flattening. The Fine works well for mild flattening and raising a slurry on Naniwas.
Fine is 600 and yeah, their edges aren't pretty. EF leaves an absolutely Stunning edge (1200 grit). Looks better than most FINISHERS under the scope. It's that regular. Still wouldn't recommend shaving off it. 
You CAN go to other stones after the F (600), but I'd HIGHLY recommend continuing with DMT's after it because their speed cleans it up quick while many other stones will take a while (600 DMT to dilucot would be a chore). That's probably why it's so commonly sold as the combo duosharp (600 and 1200 together). Also, I like it because it gets relatively little use, so while my 1200 could grind out chips fast when I bought it, over time it's become less effective at it... the 600 getting so much less use, is still quite fast at it.
EEF (4000 grit) came out a few years after I had started using the EF too EE (1200 to 8000) as my standard method.
When I bought the DMT combo, I spent a good while trying to find a 3k-5k stone to stick in between them, and I tried a LOT... but when I actually started honing a ton of razors, it became clear that a middle stone slowed me down... very few took more than 30-50 passes on 8k off the 1.2k... that's less than a minute. No reason to bother with a middle hone in my book. I would say the EEF is probably better suited for tool honing when you Don't want as much polish as the EE gives you.
You CAN go to other stones after the F (600), but I'd HIGHLY recommend continuing with DMT's after it because their speed cleans it up quick while many other stones will take a while (600 DMT to dilucot would be a chore). That's probably why it's so commonly sold as the combo duosharp (600 and 1200 together). Also, I like it because it gets relatively little use, so while my 1200 could grind out chips fast when I bought it, over time it's become less effective at it... the 600 getting so much less use, is still quite fast at it.
EEF (4000 grit) came out a few years after I had started using the EF too EE (1200 to 8000) as my standard method.
When I bought the DMT combo, I spent a good while trying to find a 3k-5k stone to stick in between them, and I tried a LOT... but when I actually started honing a ton of razors, it became clear that a middle stone slowed me down... very few took more than 30-50 passes on 8k off the 1.2k... that's less than a minute. No reason to bother with a middle hone in my book. I would say the EEF is probably better suited for tool honing when you Don't want as much polish as the EE gives you.
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DMT's are great so long as you understand their nature and "features". When new, they tend to have a scattering of coarser than specified grit which is VERY well adhered. Since they do not wear like waterstones, this is an issue until you have managed to fracture the "proud" diamond bits or have rubbed them out of the nickel plating that holds them on. Until they are gone you get deep scratches for the grit.
Diamonds held to steel plates with nickel plating have NO give at all, period. No rolling grit, no "slurry" other than steel swarf, nada. The diamonds are aslo fairly acute pointed, and so scratches from them will be fairly narrow and deep with a well defined sharp valley at the bottom. This results in stress concentrations around the scratches, especially near the edge, and resulting fractures and microcracks following the scratches.
DMT's remove steel very quickly, leave a decent to excellent finish in finer grits, and stay flat, all real advantages. Just remember that high pressure will do a couple bad things -- first and worst, it will roll the diamond grit off the plate, rendering it useless. I've done it, more than once. I learn slow sometimes. The other bad thing is microcracks and deep scratches near the edge resulting in poor condition steel that will fail later, causing microchipping of the apex.
Wear them in a bit, use light pressure, and avoid setting the bevel with anything coarser than an extra fine and DMT's are fine tools. Personally, I only use them to remove large amounts of steel while doing something like correcting the geometry of a GD66 that probably should have been recycled instead of sold. Even with knives I try to avoid establishing the apex with anything coarser than a 1000 grit stone, the edges last longer.
Diamonds held to steel plates with nickel plating have NO give at all, period. No rolling grit, no "slurry" other than steel swarf, nada. The diamonds are aslo fairly acute pointed, and so scratches from them will be fairly narrow and deep with a well defined sharp valley at the bottom. This results in stress concentrations around the scratches, especially near the edge, and resulting fractures and microcracks following the scratches.
DMT's remove steel very quickly, leave a decent to excellent finish in finer grits, and stay flat, all real advantages. Just remember that high pressure will do a couple bad things -- first and worst, it will roll the diamond grit off the plate, rendering it useless. I've done it, more than once. I learn slow sometimes. The other bad thing is microcracks and deep scratches near the edge resulting in poor condition steel that will fail later, causing microchipping of the apex.
Wear them in a bit, use light pressure, and avoid setting the bevel with anything coarser than an extra fine and DMT's are fine tools. Personally, I only use them to remove large amounts of steel while doing something like correcting the geometry of a GD66 that probably should have been recycled instead of sold. Even with knives I try to avoid establishing the apex with anything coarser than a 1000 grit stone, the edges last longer.
The EE's (and maybe others now), are supposed to have that "Breaking in" done in the factory now. Can't comment. Mine never had that problem (and was purchased before that was a thing) but I did use it for a few knives before starting with razors as insurance against it.
The 600 and below certainly have that problem. 1.2k does but to a lesser extent. In any case a few knives (or any tool), seems to fix it. The only thing is razors don't do so effectively (low force and low mass). Related to that, if you're breaking diamonds off a DMT with ANY amount of force with a razor, your DMT is defective. A Chisel? Sure, I could see someone having to be careful, but not a razor.
The 600 and below certainly have that problem. 1.2k does but to a lesser extent. In any case a few knives (or any tool), seems to fix it. The only thing is razors don't do so effectively (low force and low mass). Related to that, if you're breaking diamonds off a DMT with ANY amount of force with a razor, your DMT is defective. A Chisel? Sure, I could see someone having to be careful, but not a razor.
kelbro
Alfred Spatchcock
My current supply of diamond pastes for my balsa strops will last into the next millennium so I don't see myself buying any but has anyone here used any of the DMT compounds? I see the kits advertised and some single packs.
Chan Eil Whiskers
Fumbling about.
Good thread. I learned some good stuff reading it. I don't have any diamond stones though so I have nothing to add.
Thanks for the good content.
Happy New Year,
Jim
Thanks for the good content.
Happy New Year,
Jim
I have tried using the DMT EF and the EEF (broken in). The results are grate, until you try to finish the razor. Micro chips starts to form, or the edge fails during the first shaves. I have even tried using higher grit vetrified resin bounded stones with the same results.
I think the diamonds stress the edge, beyond what is visible under the microscope. Plastic deformation causes strain hardening, thus the edge becomes brittle. I understand that plastic deformation is needed to remove metal, but the diamond cut deeper than an equivalent synthetic stone.
I only use diamond plates if i am removing large chips. However, i still need to use a synthetic stone to "convert" the edge to finish the honing progression.
This is just my experience.
I think the diamonds stress the edge, beyond what is visible under the microscope. Plastic deformation causes strain hardening, thus the edge becomes brittle. I understand that plastic deformation is needed to remove metal, but the diamond cut deeper than an equivalent synthetic stone.
I only use diamond plates if i am removing large chips. However, i still need to use a synthetic stone to "convert" the edge to finish the honing progression.
This is just my experience.
