Diamond Machining Technology (DMT) D8XX Dia-Sharp Diamond Sharpening Stone Bench Plane, Extra Extra Coarse, 8 Inch

I ordered the DMT Extra Course 220 grit and Extra Extra Course 120 grit. Both arrived yesterday in perfect condition. Diamond surface coverage Complete and Even. Edges and corners machined and beveled/rounded perfectly on the D8XX. The others are not beveled. As a young man, my Grandfather taught me how to sharpen my lawn mower blades with a standard bastard mill file until the blade would shave hairs from my arm. That was over 45 years ago. In the ensuing time I have developed the ability to put a razors edge and beyond on the full spectrum from axes, chisels and plane blades to the most expensive chefs knives. I have put the DMT 8000g plate to protracted use on O1 and A2 steel and find it flawless as well. I use an old worn out file to condition de-ruff the edges and corners like any new stone needs. The grit begins aggressive and then settles down to the grit indicated after use. If I may offer, compare your plate abrasive to the same grit of sand paper after the paper is briefly used on wood. These plates will be used hard on 58rc and above steel. If they have any inadequacy, I will revise this opinion proportionately. For now they have arrived in perfectly made manner. I rarely say anything just dont ever buy s*** again if its s***. I'm thoroughly impressed with this companies product and so far find the plates I've received to be flawless!! I am Rick, US Army Retired. Teresa's account. I am her husband.

Works excellently with fixing damaged hand plane irons to hand plane soles and quickly restores chipped, kitchen knives. I use it as a cheaper alternative for a lapping plate for my water stones, though the DMT lapping plate has better flatness. I clean it with Comet w/bleach with lightly flowing water after rinsing. It does seem to get a slight brown discoloration even before I used Comet. Alum, from the baking aisle, also does a good job for cleaning when you make it a paste.

Pros:It cuts fast. It is large and flat. Great for reprofiling thick kitchen knives.Cons:Relative expensive. Normal sharpening does not require this and reprofiling thin blades does not.I bought it for $68. The Extra-Extra-Coarse (XXC) stone is not a cheap stone. it is noticeably more expensive than the Extra-Coarse (XC) stone. This stone can be used to lap and flatten Japanese waterstones and to reprofile knives. Nevertheless, one can use the cheaper XC stone to lap stones and to reprofile many kitchen knives. I have a XC stone and the reason I bought this stone is because this XXC can do a much faster job for reprofiling thick blade knives, like my usuba bocho. Due to the amount of metal, a thick blade knives can easily take 10 times more effort to reprofile than a thin blade. This XXC stone help.Keep in mind that just because this XXC stone can speed up the profiling process for a thick blade knife, it may lengthen the overall process for a thin knife. This is because this XXC stone leaves very deep scratches on the knife blade which need to be polished out.

This will really save you a lot of time if you sharpen even a little. As a classroom teacher I am constantly needing to repair chipped chisels and plane blades. A few strokes on this and chipped edges are clean and ready to be honed and polished. It also does a nice job flattening water stones. I also prefer to sharpen with this instead of a grinder (unless the edge is really badly damaged) as it is more precise and has no risk of burning the steel.Note: After the initial break in period it may seem that is no longer as coarse. I'm not sure why this is, but all diamond stones seem to do this. However I have been using this for a year now and it still removes steel very quickly.

As a lifelong woodworker I got this stone to flatten the backs of chisels and plane irons prior to sharpening. Getting the back flat is just as important as getting the bevel honed but is much harder as you usually have to remove about 10 time maybe 100 times as much metal. Believe me doing the bevel is a piece of cake. I was hoping that this coarse diamond stone would work better than a piece of emory paper taped to my cast iron saw table top. When I opened the package the surface did indeed feel like 120 grade sandpaper. For the first few minutes it cut huge scratches in the back of the chisel I was flatting, using water as a lubricant, and after about 15 minutes grinding it was pretty flat. But by that stage the surface of the stone did not feel like 120 grade but more like 200 grade. Then I flatted the back of an old Stanley plane blade and after about 30 minutes of scrubbing the blade was still not flat and the grade was down to about 300 grade. So either diamonds are falling out or getting crushed smaller. So I had only owned the stone for about one hour and the friggin' thing is half worn out already.At least with an Arkansas or Japanese water stone if the surface is damaged you can resurface and start again but with this stone once the diamonds fall out of their metal plating they are gone forever and the stone IS WORTHLESS. I will use this until all the diamonds have fallen out but I will not buy another diamond stone under any circumstances

This is for the Dia-Sharp Continuous Diamond - Extra-Extra-Coarse diamond plate. First plate had an obvious manufacturing defect and was promptly replaced. The 2nd one was the usual high quality DMT product. This plate is for removing a lot of metal fast and this is what it does well. It is too coarse for sharpening or for flattening other stones. It leaves deep scratch marks. I needed to change the primary bevel angle on a couple of plane blades and my coarse DMT was taking too long so I got this one. It did the job! Please note you will have to push a little harder with this extra extra coarse DMT since it really digs into the metal.