In this post, I list suppliers opinions from Best, Dan's, and Preyda
https://sawmillcreek.org/showthread.php?276528 and here is the list:
When Dan's says "Black", that seems to correspond to "Surgical" from Best and Preyda. In some of their literature, Best simply uses the term Black.
Brand Type Density Grit Grit Comment Preyda soft Medium 400 600 Preyda hard Fine 600 800 Preyda hard black Extra Fine 2000 3000 Preyda translucent Ultra Fine 4000 6000 Preyda surgical black Extra Ultra Fine 8000 1000 Dan’s soft Medium 400 600 Dan’s hard Fine 600 800 Dan’s true hard Extra Fine 1200 + Same as Translucent Dan’s translucent Extra Fine 1200 + Same as true hard Dan’s black Ultra Fine 1200 + Best soft 1200 12 micron Best hard 1500 10 – 11 micron Best Black Surgical 2300 2500 7 – 7.5 micron Best translucent 3500 4000 5.5-6 micron
It gets worse, Dan's and Preyda list 5 stone grades. Best lists 4.
Dan's and Preyda indicate that translucent is before "Surgical".
Best, however, has a different take (opinion).
https://www.danswhetstone.com/inform...ne-grades-101/
https://www.bestsharpeningstones.com...ng-stone-grits
As a reminder, they grade Arkansas stones by looking at the Specific Gravity. Higher is better (in theory). Best lists these numbers:
Dan's lists their lasts three stones as having a specific gravity of 2.55+ and states that their Black (surgical black) is the finest.Soft Arkansas - Specific Gravity 2.22 | 12 micron | .00047" | Grit Equivalent: 1200. The Soft Arkansas is close to the 12 micron lapping film but clearly finer than the 800 grit diamond stone.
Hard Arkansas - Specific Gravity 2.36 | 10-11 micron | .00041" | Grit Equivalent: 1500. It is a little coarser than the 9 micron lapping film but finer than the 12 micron film.
Black Arkansas - Specific Gravity 2.55 | 7-7.5 micron | .00028' | Grit Equivalent: 2300-2500. While the Black Arkansas did have a few larger scratches, overall, it is a little finer than the 9 micron lapping film.
Translucent Arkansas - Specific Gravity 2.53 | 5.5-6 micron | .00023' | Grit Equivalent: 3500-4000. It is clearly finer than the Black Arkansas. Most closely resembles the 5 micron lapping film.
If you look at Best, They show that their Black has a higher density than their translucent, but, then they show high resolution images of the scratch pattern from their Black compared to their Translucent Arkansas. Best claims to base their grit equivalent (micron equivalent) based on comparing the scratch pattern to graded abrasives. Their result is that the Translucent has the "finer" edge.
If you are still with me, I had some general assumptions.
- Any stone from any supplier will have variations, so, from the same supplier, I expect that I will find stones that will produce results that are out of order, especially for their finest stones.
- Some kind of consistency between suppliers based on grading. For example, if Translucent usually produces the finer edge from one supplier, I would expect that from another.
Dan's directly states that the specific gravity is pretty much the same for their finest three stones and that stones #2 and #3 are essentially equivalent. In other words, no reason to buy their Translucent because it should produce the same edge as their "true black". But buy their black because it will produce the finest edge.
Best states that although the Translucent does NOT have the highest specific gravity, the produced scratch patterns are smaller.
I have been focused on finishing a project and shop clean-up lately.... and I am not sure if my current skills will allow me to obviously state which produces the finer edge and I do not have the tools to check patterns. part of this is strictly academic I suppose, but I have some practical uses.
I own tools specifically designed to sharpen knives, probably more than is reasonable. I have a few knives that resisted a sharp edge off one of my belt sander knife sharpeners, but after proper rehabilitation with the belt sander sharpener, it took a wicked edge off the Arkansas stones. For the record, I do not shape, repair, or restore edges with the Arkansas stones.
So, any opinions on (surgical) black versus Translucent? (especially with respect to different suppliers).