|Posted: Thu 29 Sep, 2005 8:40 am Post subject: Review: DMT Duo Sharpness Plus (Diamond sharpner)
With the help of my younger brother, forumites Patrick J, Michael 'Tinker' Pearce, Trish Davis and Jim Frank, I've received the sharpening stone I ordered as my birthday gift to myself today.
The stone looks like this:
Upon opening the box, disappointly that I didn't see any diamond. Well, the fact is that they are so small that it is not visible. They scattered on the silvery surface made of nickel. Between the metal surface there were regularly patterned holes. These recessed holes was designed to take the waste from the sharpening so the diamond would not be clogged easily. According the manual, using the stone was ideal in dry or water lubricated situation. Since I don't want my sword to rust, I decided to use it dry, always. There's an area of continuous metal on each side, which is for sharpening fine pointed instrument that may be caught in the recessed holes if it was sharpened in the "normal" area.
The grit I got were fine and extra fine. Here are the descriptions from their website:
FineĖ Restores to a fine edge any knife or tool that is slightly dull. Many of our customers consider the fine grit to be a medium/all purpose sharpener. Professional Chefs and gourmet cooks prefer using our fine grit models. For woodworkers and sportsman who are stepping through the grits, itís the edge refinement step done before micro beveling and polishing. Color code: fine (25 micron, 600 mesh) "red".
Extra Fine- Refines and polishes the sharp edge to razor sharp perfection. If you are new to sharpening or if you do not need your knife or tool edge to be as sharp as absolutely possible, this grit is not recommended. But if itís not sharp until itís sharp enough for you, this is the grit you are looking for! Color code: extra fine (9 micron, 1200 mesh) models "green".
Now, let's talk about my previous experience in sharpening. I have used very affordable stones made of coarse and fine silicon carbide and these are considered fast stones that removes lots of material in a short time. I also have the highest grade arkansis finishing stone from knife-art.com that was given to me as a gift from Joe Leung.
The arkansis one can be found here:
Usually, for shaping a blade geometry like smoothening the secondary bevel, I would use the coarse silicon carbide side. It takes like 200 to 400 strokes on each side to flatten the surface of the contact area. This leaves the edge with a coarse feeling and draggy serration.
For actual sharpening or repairing a slightly dulled blade, I'll use the fine side of the silicon carbide. Again, it'll range from 160 to 320 strokes on each side for me to make the edge reflecting no lights at all, being totally sharp. This leaves the edge with an medicore smoothness and high serration ability.
Most of the time, I stop here, because I like serration ability as well as cutting ability. The fine side of the silicon carbide stone was the balance for that.
If I feel crazy enough to move on to the arkansis stone, it'll take a MUCH LONGER TIME and MANY MORE STROKES (we're talking about the number with 4 to 5 digits ) on each side to sharpen the edge. The edge will look like somehow polished (but not to the original polish), feels very smooth, and the edge line is very smooth as well. However, this also means while being razor sharp, it has no serration ability left on the edge. More effort, less return to my opinion. But this stone used to be my only stone so I used it a lot in the past. It has to be used with oil and the work, my hands and the stone would usually end up very messy.
So, what will the DMT DuoSharp Plus stone do? I took out an Atrim short sword to test it.
First I tried the fine side and I can feel from my hand that this stone sharpen FAST! But how fast is it compare to the silicon stone's fine side? I think it was just SLIGHTLY faster at that time, not knowing the end product would be different. However, it has a big advantage over the other stones that it always stay flat and would not wear off with a slump, thus the angle of sharpening is easier to control.
It took about 20% less strokes than the silicon fine side to do remove the shine on the edges that was left by the some cuttings. Moreover, when I touch the edge, the edge is less draggy than the one produced by the silicon fine side. So it has a higher grit, yet sharpening faster! The serration is good, not draggy and sharp.
After spending 1.5 hours to get 50% length of both side sharpened with the fine side, I then moved to the extra fine side to see just how extra it is. Upon first trial, it doesn't seem to have visual difference. In fact, I had a moment of confusion whether it was the same grit as the fine side.... since I couldn't tell from my eyes alone. Then I touched the surface and moved my fingers along. Only then could I feel the difference between the grit.
The extra fine grit is not as polishing as I expected when compare to the arkansis stone. It seems that it may take a DMT ceramic to attempt to match the arkansis finishing stone's fineness. But then, I never wanted such fineness where I lose all serration ability.
The extra fine's end product is a smoother feeling edge than the fine grit, yet still maintain a very good serration ability. This seems ideal for my preference in sharpening swords! Another bonus is that it didn't take many strokes to upgrade the edge from the fine to the extra fine. Say, 40 strokes each side will do the job! This is a considerably much easier step than a step up from the fine silicon stone to the arkansis finishing stone. Well, in fact, the extra fine side of the stone cuts almost as fast as the fine side did, so I may consider starting JUST from the extra fine side if I feel the edge wasn't in too shiny shape.
Now, after all the work, it's time for cleaning. Without the use of oil, thus no sticky feeling, I can clean my hands completely with just a soap and easy rubbing. However, cleaning the stone was a totally different matter though! While instructed to use water to clean, I didn't find the wastes getting washed away from the stone at all! I tried the soap, a non-petrolium product that the instruction said could be use. No use. Used teethbrush. Futile. Used light hand pad 3m Scrotchbrite with very very light scrubbing, fearing that I may damage the nickle surface. NO USE......
Ok, I give up... and let the stone be all dark. :P Then when I wiped the stone with tissue to dry of the water, I found that my tissue absorbed a major amount of the waste along with the water. AHHHH.... so that's it! Just use water, then wipe! Doubtlessly, after the first 1.5 hours of use, there are wastes that rested in the recess holes and some area of the nickel that I could not clean. I'm not used to seeing waste being left on the stone surface because I could always clean the arkansis stone very thoroughly (and I don't clean the silicon stone at all. They are very cheap). So it seems that the diamond stone cannot be cleaned as thoroughly as the arkansis one. Yet I think it wouldn't affect it's performance until I really clogged it badly.
In the end, I've to thanks all who had helped me to get the stone, and the stone is very impressive. I'll use it on my Brescia Spadona when it requires sharpening, instead of using the silicon stone as I did before.
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