Diamond Cross Sharpening Stones

Sharpen Faster and Cleaner with These Diamond Stones

Diamond Cross Sharpening Stones

Diamond Cross Sharpening Stones

Diamond sharpening stones are a great way to keep your cutting tools sharp and ready for any job. Unlike water stones they'll never dish out, won't crack if dropped on the floor (or if you inadvertently drop a tool onto them), and they're virtually maintenance-free. They also cut noticeably faster than water stones, so you can get the edge you want, and get back to work, sooner. Which makes them especially suitable for novice woodworkers.

Diamond Cross is a new line of diamond sharpening stones from British manufacturer M.POWERThe stones come in five styles:

Benchstone2-3/4" x 8"300/1000
Router Bit Sharpener1" x 3"300/600
Credit Card Stone2" x 3"300/600
Single Handle File1" x 5"300/600
Twin Handle File1" x 4"100/300

The Diamond Cross recess pattern

These are non-continuous surface stones – a series of recesses, in the shape of crosses (hence the 'Diamond Stone' moniker) serve to collect the swarf produced during the sharpening process. The stones use monocrystalline diamonds, which are comprised of single (unfractured) crystals, unlike polycrystalline diamonds that consist of multiple particle crystals that have a tendency to break down more readily in use. All the stones are double-sided, with a rougher grit on one side, and a smoother grit on the other side (the Twin Handle File has one version with very coarse and coarse sides). 

A polymer eraser keeps them clean

While you can use them without a lubricant, I typically use water. After using the stone I simply wipe it clean and dry. You could also use a lapping fluid specifically designed for diamond stones, which serves the same purpose as water, but won't rust the metal substrate. I don't use products like WD40 and mineral oil, as they have too high a viscosity, and in fact, cause you to use more pressure than is necessary. Over time the stones do tend to gum up, but you can clean them with a polymer eraser and a bit of elbow grease.

Diamond Cross Benchstone Package

The Diamond Cross Benchstone comes with the benchstone, a storage wallet, two holders, and an eraser. You can use this benchstone for planes blades and chisels, as well as for a range of other cutting tools – knives, carving tools, spokeshave blades, router bits, insert bits, and the like. The storage wallet protects the stone when not in use, and is very handy if you take the stone to a job site. The rubber holders, which attach magnetically to either side of the stone, serve to elevate the stone so that chisel handles or other tools won't scrape against the surface you're working one, and they function well in preventing the stone from sliding about in use. The eraser does a great job of cleaning dried swarf from the stone surface. 

One side of the benchstone is embedded with 300 grit (50 micron) diamond, the other with 1000 grit (15 micron). The diamonds are embedded onto a stainless steel plate, and then the two plates are high-pressure bonded to a tool steel core plate that has, according to M.POWER, a finished tolerance of +/- 0.00175” ( 0.044mm) across it's entire length. I checked both surfaces of the stone and, as far as I could determine, they were perfectly flat.

Ample surface for all your blade sharpening

At 2-3/4" x 8" this stone is big enough to handle the largest plane blades – at least the ones in my shop – and it easily accommodates a honing guide. Initially all diamond stones cut aggressively, regardless of the grit. However, shortly after use the cutting speed will decrease, and you'll even notice that the finish they deliver will improve.

Back flattened with 300 grit stone

In the photo above you can see the result of flattening the back of a chisel with the 300 grit side of the Diamond Cross Benchstone. The back was slightly concave, and it took less than ten strokes to flatten the top 1" and achieve a consistent scratch pattern. I also used the 300 grit side to remove a couple of small nicks on the end of a narrow plane blade. Again, it only took a few strokes to re-establish the bevel angle.

Chisel back refined with 1000 grit

About a dozen and a half strokes on the 1000 grit side gave a smooth surface, with a noticeably finer scratch pattern. At this stage the back of the chisel is flat and smooth, ready to be used. Of course, you could chose to polish the back by either moving on to a 8000 grit stone, or a leather strop with a honing compound, which is generally my choice.

(L) Router bit sharpener; (R) Credit card sharpener

The router bit sharpener and credit card sharpener are essentially the same stone, albeit in different sizes. Both offer 300 grit on one side, and 600 grit on the other side. Each has an integrated handle, which makes it easier to hold the stones, keeping your fingers off the diamond surface and away from the tool edge.

Regardless of the names given to the stones, both can be used to sharpen small cutting tools, router bits, insert bits, small chisels, and the like. Given the price differential (about $3 US), I think you get much better value with the credit card size stone, with it's 100% larger surface.

In the photos above you'll notice that I"m using the optional stone holder. These are little rubber 'feet' that have a couple of embedded rare earth magnets that lock onto the underside of the stone providing a very firm grip. They keep the stones from moving about on the work surface, and elevate them above the work surface. As notes above, a pair of them come with the benchstone.

Single Handle File

Similar to the two stones mentioned above, M.POWER also offers two diamond files, one with a single handle (1" by 5", excluding handle), the other with a double handle (1" by 4", excluding handles). Both have the standard 300/600 grit surfaces, while the double file is also available in a 100/300 grit format that is ideally suited for sharpening garden tools, axes, adzes, drawknives, and the like. I much prefer the single handle file, which I found very convenient for sharpening knives, as you can make a long continuous stroke.

While I haven't been using these Diamond Cross sharpening stones for months on end, they have, so far, proven to be very effective. If you are thinking of moving to diamond stones, you certainly won't be disappointed with any of these M.POWER products. 

  • monocrystalline diamonds bonded to stainless steel plate
  • non-continuous surface
  • double-sided
  • precision ground tool steel core plate (+/- 0.00175” ( 0.044mm) 
  • 5 different formats
  • 3-year warranty
Benchstone Set – $89.95 US
Router Bit Sharpener – $19.95 US
Credit Card Stone – $22.50 US
Single Handle File – $22.50 US
Twin Handle File – $24.50 US
DC Diamond Stone Holder (pair) – $11.50 US
MADE IN:UK + overseas components
SOURCE:Locate a Dealer

Carl Duguay
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