DMT vs. Waterstones

W

williamisthe1

Joined
Apr 11, 2015
Messages
181
Hey guys I'm looking to upgrade my stones I've been using a sharpmaker then moved on to free handing on a generic double-sided coarse and fine stone then a Spyderco 306UF and finish on a strop but feel like I can do better. I want to sharpen my folding knives to mirror polish. I use S35VN, S30V, D2 and, CTS-XHP steels. So what do you guy recommend DMT or waterstones and if waterstones what brands and grits? Thanks
 
You get a mirror polish from abrasives that are approximately 5000 grit JIS, or roughly 3 microns. The Spyderco UF is right there at 3 microns. If you're not getting a mirror polish now, I would guess it's because the stone you're using before the UF is not fine enough for the Spyd UF to polish out the scratches and leave behind a bright polish.

I've achieved a mirror polish on steels with a waterstone progression of 150 -> 1000 -> 5000 . I've also achieved a mirror polish with DMT stones, followed by the Spyderco UF: DMT XXC , DMT C, DMT EF, Spyderco UF.

DMT plates behave completely differently than waterstones. I've had better luck with the DMT plates myself. I think you can achieve great results with both; they are just different and my ability to use waterstones isn't refined as my ability with DMT plates. Some people are better using one versus the other. Jason B happens to be good at both. :) I'll leave waterstone recommendations to him, or another member that has solid experience and skills with waterstones.

Brian.
 
Use the diamond plate with the little hollow dimples for flattening the water stones.

This is a Coarse / Extra Coarse DMT which is like 320 / 200 or close to that (see their web info if you need exact info).

I have used the diamond plate on like A-2 steel etc. but for the most part just use the stones on the blades and the diamond plate on the stones.
If you want to really remove steel to reshape the edge etc you are much better off going with a super cool running powered grinding wheel like one of the Blue Norton 3x grinding wheels around 46 grit then start in on one of the Shapton water stones about 320 or 500.

You don't need all these but if you want wide polished bevels (as opposed to just the micro bevel polished) then the mirror looks best if you work through most or all of these grits.

The Shaptons are really capable.

I use them in my Edge Pro as well.

PS : grits 1000, 2000, 5000, 8000
bellow that is for metal removal not polishing so that is up to you depending on how much metal you need to remove.
I am a fan of really coarse stones to start like 120, 200 etc but don't get crazy with them. Mostly to cut the metal BEHIND THE EDGE back rather than use it on the actual edge.

I go to 15,000 and covet a 30,000 but that is mostly silliness on my part. 8000 looks great as long as you get the scratches out from the previous stones and don't cut corners by using cheep junk stones bellow that. I am darned impressed with the results coming off my Edge Pro at only 5000 grit. Looks darned good.



 
Last edited:
I almost forgot.
You will have more fun with water stones if you also get a nagura stone.
It probably won't look at all like this. They make synthetic ones as well.
Use it to clean the stones like an eraser.
Slurry ?
Forget slurry.
Slurry is stupid and a waste of time but the nagura works seriously well to get the metal glaze out of the pores of the stones. Then wash the crud (slurry) off the stones under the running water tap.

 
Wowbagger said:
I almost forgot.
You will have more fun with water stones if you also get a nagura stone.
It probably won't look at all like this. They make synthetic ones as well.
Use it to clean the stones like an eraser.
Slurry ?
Forget slurry.
Slurry is stupid and a waste of time but the nagura works seriously well to get the metal glaze out of the pores of the stones. Then wash the crud (slurry) off the stones under the running water tap.

Click to expand...

+1

There is something romantic and zen like about waterstones. However, Some of the steels the OP mentioned can sometimes be tough on waterstones. The DMT plates will cut anything and everything. For some reason the CV on my case sodbuster jr is really hard and doesn't take an edge easily on my higher grit waterstones. I use a DMT coarse then finish on a strop. No mirror polish, but it's razor.
 
I believe you will need diamonds in order to do any good with some of those high carbide steels. Jason can tell you much better, but I know I've seen him put a mirror polish on high carbide steel using DMT plates. I believe he takes it down to EEF and strops with diamond pastes on hardwood.
 
Why do you want to polish the edge of high carbide steels?

Performance is decreased, maintenance is more difficult and tools needed are expensive. I polished edges at one time because I was searching for the highest level of sharpness, it was cool but the polish can be like gold fever and make you lust for more. Eventually, we all settle down to a more reasonable level with a practical sense of edge performance.

You can mirror polish a blade in many ways, with DMT stones I finished with the EEF and stropped with 6, 3, and 1 micron DMT pastes on a balsa, hardwood, MDF, poplar, leather, felt, paper, etc, strop. I've used a few different stops ;) Today I use the DMT Coarse and a 1 Micron strop, not as pretty but a better performing edge and somehow just as sharp.

For the steels listed I would only recommend the Shapton Glass series of waterstones. Starting at 500 grit you would need to follow with 1k, 2k, 4k, 8k, then maybe the 16k or a strop with 1 micron diamond or CBN.
 
droptrd,

CV
Click to expand...
CV should pose absolutely no problem in the world for a Shapton water stone. It is engineered to abrade alloy steels that are far tougher to cut. In fact the whole point of CV is that it is easy to sharpen.

I am thinking, unless I misunderstand you, that you just need to do your SHARPENING on a coarser water stone then do the refining and polishing of that edge AFTER IT IS SHARP on the finer stones.

I never try to "touch up" an edge on a fine stone. I have finally learned from much time and frustration to go to a coarser stone to cut the steel then just use the fine stone to make it pretty and smooth. Of course one can strop to touch up if the edge hasn't gotten too dull but I abhor stops for the damage they do to the edge geometry.
 
Last edited:
Some of the steels the OP mentioned can sometimes be tough on waterstones.
Click to expand...

I think you mean : on natural, quarried, water stones. Am I right ?

Jason (or any one else),

Is there REALLY anything a Shapton won't cut besides a ceramic blade ?

Speaking of stropping. I was trying to strop a ceramic blade on a rock maple strop with 600 grit diamond paste on it. Never made a significant change until I took it to one of my EEF diamond plates. I had relaxed the sharpening angle of the edge some using diamond paddles and was attempting to make the edge shave sharp. Ha, ha, ha, it wasn't shave sharp from the maker even though their shtick was "Ten times sharper than any other knife" or some such baloney.

See top knife in this photo. Nice little knife but dull as a river rock. (compared to all of my steel knives).

 
Wowbagger said:
droptrd,


CV should pose absolutely no problem in the world for a Shapton water stone. It is engineered to abrade alloy steels that are far tougher to cut. In fact the whole point of CV is that it is easy to sharpen.

I am thinking, unless I misunderstand you, that you just need to do your SHARPENING on a coarser water stone then do the refining and polishing of that edge AFTER IT IS SHARP on the finer stones.

I never try to "touch up" an edge on a fine stone. I have finally learned from much time and frustration to go to a coarser stone to cut the steel then just use the fine stone to make it pretty and smooth. Of course one can strop to touch up if the edge hasn't gotten too dull but I abhor stops for the damage they do to the edge geometry.
Click to expand...

What I am saying is one particle cv knife I own just seems harder. The others I own are no problem. My shaptons and Kings WILL sharpen it but it seems to take more time and work than others. However my shapton pros are 1k and 5k and kings are 1k and 6k. Maybe having something in the middle will help. Or something lower. But the dmt works for this knife. There are alloys out there that are really slow on waterstones. My knives of Alaska camp knife in D2 is a real SOB to sharpen. I don't let it get in bad shape either. Now it only gets sharpened on diamonds.

So all I was really saying was, while I prefer waterstones, they are not a universal solution for all situations. I'm not trying to start a war with all the hard core waterstone guys, I'm just sayin [emoji6]
 
The main issue with sharpening modern steels is the Vanadium content. At 4% it starts becoming an issue for most stones, all but the highest quality abrasives start failing and it becomes very noticeable that something better is needed. At 9%+ Vanadium you can get stones like the Shapton Glass to work but it's not the best option. At this point Diamond and CBN really start to take over as the ideal abrasive to use.

Steels like D2 have Chromium carbides, these are softer than Aluminum oxide (main abrasive in most stones) so pretty much anything will sharpen it. Harder abrasives tend to work better though, it's the name of the game, one object needs to be harder than the other.
 
with modern and tool steels like that, I would opt for some DMT stones, even though I'm a diehard water stone user. Jason B. does raise an excellent point, but in your situation I would go with some DMT coarse and medium stones, and medium to fine Shaptons.

Connor
 
williamisthe1 said:
I just ordered a DMT coarse and will see how it goes from there.
Click to expand...

Excellent choice!

I would recommend picking up some 1 micron diamond compound to use on a wooden or leather strop. This really enhances the edge produced by the Coarse DMT Plate and yields impressive sharpness on a wide range of steels. This is actually how I sharpen most of my folding knives.
 
Oh I don't want to start a serious war here. I'm just visiting and learning and relating my limited experience and you are telling me your experience.

The coarser stone work with an immediate stropping after (I assume on a soft strop with diamond paste) is intriguing. Kind of a mini serrated edge if you will. Hmmmmm I got to try that.

I need to look at the vanadium thing closer. Most of what I have been reading in my short time of looking at these alloys is that the vanadium helps with sharpen ability but now I am learning that at some tipping point it starts to work against us.

D-2
Click to expand...

Lately I have been sharpening CTS-XHP Cold Steel and ZDP-189 Spyderco From Seki City no problem. Seems like that is right up there with D-2.

The photo with the white stones shows one of the thick plane blades I was making from old Nicholson files I ground the teeth off of . . .

(these are the good old stuff before they went to Mexico (I have proof the Mexico made are not as hard if you want to see it)).

The Shaptons sharpen it fine. The low grade 80 grit stone stopped cutting in no time and would need to be freshened on a diamond plate so I ordered the Shapton 120 . . . it cut, and cut and cut and there was no let up.

Of course these are not super steels but harder than about any knife except the ZDP-189 I mentioned and I found more important than hardness was when one got into a wide bevel. That was power grinder time . . . but the little tiny bevels we are talking about on a curved knife where there is just lots of force per square inch because the area is so small I'm just not seeing a NEED for diamond if one has a coarse stone like the 120 Shapton or there a bouts.



The chisel is Hitachi blue paper steel; not super steel but no slouch in the hardness department. As you can see mirror polished and I steepened the bevel from about 25 to about 30° to eliminate chipping while cutting super hard woods. These bevels are seriously wide not just cutting on a curved, bellied, knife blade and a little thin bevel.



Too hard to sharpen on a Shapton . . .

I can’t wait to get something that MONSTER. I am thinking it is going to have to be a Phil Wilson CPM-10V or some such. I better start saving my pennies.
http://www.bladeforums.com/forums/s...based-on-Edge-Retention-cutting-5-8-quot-rope

I am pretty well fixed for diamond plates and paddles and stuff. And that's not including my various diamond pastes and maple strops. It is just that I haven't found a real need for them on knives. I originally got the big plates for flattening and polishing, as far as they go, on the big flat backs of A-2 woodworking plane blades. That was a frustrating waste of, what seems like looking back on it, half a life time. I find I am better off going way coarser and using Norton Zirconia Alumina cloth sanding belts glued to a flat surface. The zirconia is way, way sharper and darned hard enough for sure.

The diamond paddles I use to do quick touch ups on carbides and bimetal bandsaw blades . . . good for sharpening drill bits too.

I just have never run into a knife I need them on. Sounds fun though.

 
Last edited:
You must log in or register to reply here.
Back
Top