This is the third installation of the Wicked Edge Precision Sharpener’s (WEPS) progression of stones under the microscope. So far, we have looked at the Wicked Edge stock diamond and ceramic stones, and the Wicked Edge Chosera Stones under the scope. In this post, we will look at the complete Shapton Pro WEPS stone progression. I highly recommend reading the stock and Chosera progressions first, as they both contain information that will be applied to this post.
The knife is a Maestro Wu bombshell steel folding knife with the angles set to 20 degrees per side. All pictures are taken with a Veho 400x USB microscope, and the actual dimensions of the pictures are all 1mm wide by 0.75mm high.
Once again, I will be doing a series of scrubbing strokes followed by sweeping strokes at each grit. Scrubbing strokes are aggressive, and are an up-and-down motion used to establish the scratches at each grit, and to account for any minor deviations due to the tolerances of the angle cube, and dishing in the stones, etc.. The sweeping strokes are alternating strokes the span across the entire edge from heel to tip or tip to heel, and they establish a straight line at the edge of the edge. I don’t generally use circle strokes with anything other than the WEPS 100 diamonds.
One major difference between the Shaptons and almost every other synthetic sharpening stone is the way they are used in order to achieve the maximum results. Simply put, Shaptons have a different sharpening approach, or “philosophy”. The majority of water stones, including the Chosera stones, benefit from the paste that is formed while sharpening, The paste adds a level of polish and cleans up the edge of the edge, making the knife seem shinier and sharper than the actual advertised grit.
Shaptons do not generate a paste. They create a swarf, which is a mixture of water and metal debris, with no loose abrasive particles or bits of the stone matrix. Swarf is not desirable for the Shaptons as it actually inhibits the action and precision of the stones – especially at the 5K, 8K, 15K, and 30K levels. Shaptons rely solely on creating densely packed consistent scratches, which gives every level a “true” scratch pattern – without any enhancements. This gives the Shapton edges a sharp, yet smooth feel to them that gives the user complete control of the cutting action. By the time you get a mirror (at the 5K), the scratches are so consistent and close together, they form a mirror finish.
In the case of the Shaptons, the cleaner the surface is, the better. They consequently use more water, and since it doesn’t get absorbed into the stone, there is more runoff.
Using a slurry (loose, usually same grit abrasive on the surface of the stone that makes abrasion faster) on the lower grit Shapton Pros is acceptable, although not usually necessary. IMO, a slurry is usually not necessary past the 1K Shapton Pro level.
Shaptons have a huge range – from #120 to 30K (122 microns to 0.5 microns! – here is a WEPS grit comparison chart). When coming off the WEPS stock 600 diamond plate (16 microns), the #120 grit is a rather large step back, but man it can really take out those diamond scratches quickly! :D
Up first is the WEPS Shapton Pro #120 stone, scrubbing.
Since this is such a large step back from the WEPS stock 600 diamond, I did not use a slurry.
You can see the relative shallowness of the scratches, but it leaves a very serrated edge of the edge. In the next few grits, we will see the whole idea of the Shaptons creating a controlled “retreat” of the serrations rather than trying to enhance the finish at each level.
We can see the serrations at the edge of the edge have changed from more of a chipped pattern to slightly wavy one.
The #220 and #320 Shapton Pro stones are excellent for a non-diamond approach to chip removal and profiling. The #220 is a hard, aggressive stone that is generally better suited to softer steels, and the #320 is a softer, yet every bit as aggressive stone that is generally better suited for harder steels.
The #220 or #320 is an excellent crossover stone from the WEPS stock 600 Diamond plate.
As you can see from the #320 sweeping picture, the consistent line of points at the edge of the edge resembles a microscopic serrated knife. The #320 is one of the most popular foundation stones in the Shapton series, and this is why!
At first glance, the Shapton 1K is a bit rough – and it is a rather coarse 1K stone. The stone is actually classified as a “Coarse/Medium” stone – it’s actually much more similar in results to the 800 Chosera. This edge is now at a basic sharpness level. When coming off the stock WEPS 600 diamond, the 1K is a good lateral move.
We are still following the idea of a gradual reduction in the serrations at the edge of the edge, and you can see the edge has lost those consistent points from the #320, and there is an outline of a straight line at the edge of the edge.
The #1,500 Shapton Pro WEPS stone is a gem. This stone is coarse enough to do some repair work, while leaving a very good consistency of in the depth of the scratches that allow this stone to outperform many of the other medium grit stones on the market. This is what I personally use for a working edge.
The 2K Shapton Pro WEPS stone is another excellent stone – aside from the almost mirror, and perfectly aligned scratches (they were once referred to lining up “like North Korean Soldiers”, but I’ve always thought of the scratches as Can-Can girls), the difference between this 2K stones and others is that it will only ever produce a hazy mirror at the macro level. This is due to the no paste/swarf policy. :)
We’ve arrived at our “critical leap” – the point where the scratches are shallow enough to create a evenly reflective surface under the microscope. On the Shapton Pros, it is between the 2K and 5K.
You can see from the picture above that despite the perfection of the 2K scratches, the transition is not always pretty. While the scratches do line up beautifully, there are clearly exposed scratches still going in the wrong direction on the bevel, and the edge of the edge is quite dirty. Cleaning things up is imperative at this step, and is why I refer to the leap being “critical”.
That’s better! :D
One thing to mention from this point on is that the edge of the edge is becoming thinner and thinner as we progress. You can see from the pictures above that there are scratches in two distinct patterns at 5K, and that is due to the pressure I am putting on the edge of the edge while scrubbing. This is causing the edge to flex under the weight. If you push too hard, it will burnish, or roll over, leaving a fatigued edge that will fail to hold its sharpness for long.
With my sweeping strokes, everything has cleaned up wonderfully. This is a mirror at the macro level, although not a shiny as the 5K Chosera, and the edge of the edge is more than most people have ever experienced. Most knives and tools are sufficiently sharp at this point.
I’ve done a lot of work up to this point, and the scratches of the Shaptons work very quickly at the 8K, 15K and 30K levels if you’ve sufficiently conquered the critical leap.
I am a firm believer that if your geometry is correct, you cannot do too many strokes on a stone up to and including the 8K Shapton. This is because the edge of the edge still has enough width (as we approach 0 width) to hold up to normal use without failing. The scratches here are clearly more refined than the 5K and the purpose is to now approach the zero width window without going over.
If you think about a newly sharpened pencil easily being broken as you write that first letter or two, the same theory applies to the edge of the edge, which is becoming ever closer to being a point with 0 width. If you make the edge of the edge too thin by doing too many strokes, it will fail. This can be adjusted with geometry, but every edge will ultimately approach the same 0 width dilemma (see this post for more about the theory of over honing).
That is why I generally do not use scrubbing motions at the 15K and 30K Shapton Pro levels. I like to think of it as “polishing the 8K and 15K grooves” rather than trying to establish the 30K scratches, which would theoretically leave the edge of the edge at a 0.5 micron width (since 30K is .5 microns).
I also don’t do as many strokes as I did on all the other previous grits (I did less than 50 per side). You can still see some evidence of previous scratches, but they are most likely 5K or 8K in size. Every progression is subject to leftover scratches since each level aims to remove the previous scratches, but while I could stand to do a few more strokes to get rid of them, I think we are fast approaching a point of diminished returns.
And finally – the stone everyone has been waiting for – the 30K Shapton Pro WEPS stone. Drum roll, Please! :)
As with the 15K Shapton Pro, I only did a limited number of strokes (about 10-15 ultra light strokes per side). You can see no fewer than 3 very thin vertical scratches have been exposed – I’d put them at 8K (my last scrubbing stroke) Even at the 30K level, we are revealing previous scratches.
It’s enough to drive you mad! :D
There is a huge inverse proportion of the price ratio to the actual time of use of the 15K and 30K stones, but the results speak for themselves. No where else is there a stone option that creates such clean refinement and precision.
This will be touched upon more in the next post, which will compare and discuss these 3 progressions to each other in greater detail.