Diamond Machining Technology (DMT) WM8CX DuoSharp Double-Sided Diamond Sharpening Stone Bench, Coarse/Extra-Coarse, 8 Inch

Have you ever spent a half hour trying to sharpen a knife with a hard blade steel like s30v only to take off barely any material? If so, you know it can be a real pain in the a**. Metallurgists have been doing some crazy stuff with powdered metal alloys in the last 10 years since I started sharpening my own knives. While the old sharpening tech still works, it is painfully slow for these new super hard steels. Something more aggressive is needed. DMT plates provide extremely fast and precise removal of material. Since they are so expensive I was worried about quality because of some reviews, but mine look great. There is a slight break in, but not too long. I was able to reprofile the edge of my benchmade 535 (s30v) in about 10-15 minutes using the extra coarse side. I did not find it to be too coarse like some reviews, and the plates are very flat. I think some reviewers mistake the extremely aggressive removal rate for a more coarse grit. I examined it under magnification and the diamonds appear to be consistently sized and about 220 mesh as DMT says. It is extremely fast even with s30v, to the point that every stroke counts. Instead of mindlessly giving it a few passes and then looking, I found myself concentrating on specific areas of the blade and looking at it after every pass. It allows you to cut so much with each stroke that it is almost like a power tool. DMT says that the extra coarse is a “safe alternative to powered grinding”. This is absolutely true with the added benefit of much less likelihood of heating the blade. It would be very easy to destroy knives as well with this system if it is misused, but that is true with any powerful and useful tool.

I like a sharp knife but I am far from an an expert in tool sharpening. I had a couple of fairly expensive knives that I could no longer sharpen with the stones, steel rods, and ceramic sticks that I had traditionally used. I decided to invest in a diamond stone. This DMT bench stone works great and the fine/course combo has been good to restore my dull knives or tone those that were in better shape. I liked it so much that I also bought a small pocket model and and a rod by the same company for serrated blades. I am using it in the available plastic base and I think that is the way to go. I have sharpened every knife we own, my axes, all my tree and shrub trimming equipment, and I used the diamond bench stone to flatten my old sharpening stones that were grooved from use. I am glad that I bought a larger size for all the things I have sharpened. It is easy to clean with soap and water. A solid tool investment.

Like the others have said, this is simply amazing. Even hardened steel blades grind down like butter on this unit.I have found that virtually ALL knives that you buy (with the notable exception of Moras) have the edge angles too steep, so you need to remove quite a bit of material from the blade before you can get to the honing stage. For this reason, the DMT Extra Coarse/Coarse stone is a necessity. (I bought the Fine/Extra Fine first and loved it, but soon realized that I needed the Coarse/Extra Coarse to start, otherwise I would be spending hours with the Fine.)For this reason, if you are serious, just buy the Extra Coarse/Coarse at the same time as you buy the Fine/Extra Fine, along with the little plastic stand, and welcome to the world of serious sharpening!The shipping was prompt. A great transaction.

Very over priced and underwhelming. Grit is not very aggressive and you can hardly feel it on the surface. Took me 30 minutes to get an edge on the knife. One is better off purchasing a diamond plate where the whole surface is covered with the diamond grit. Not one like this with holes for the slurry to fall into there is no 100% coverage of the diamond gritWhy did you pick this product vs others?:It was suggested should not have went this rout

I was able to flatten 3 Cr-V chisels that had been nicked. I used a rolling guide and was able to grind them down very quickly, clean and square. I had no problem removing material. Wide enough for plane blades.

Perfect, larger size sharpener.Easy to use and get used to.Very well built easy to handle while sharpening.

While I think that this is a good sharpening method, note that you can not use the bench stone to flatten other sharpening stones. You might be able to get away with flattening a softer stone, but using it to flatten a harder sharpening stone ruined the extra course side of the diamond stone. It still feels rough, but it does not cut very well. Trying to sharpen a wood chisel on the damaged extra course side showed very little progress. I made much more progress (it went much faster) using just the course side which was not damaged since it was not used to flatten other sharpening stones. I do not know if the sharp edges of the diamond were somehow damaged or if they broke loose, but the stone would not cut. Very few, if any, small shavings (swarf), formed when using the damaged side and it took forever to show any progress when creating a new edge.

Effective, solid, all that's needed. The included mat is folded around the bottom of the stone, out of sight, I almost threw it out.