Progressive Sharpening vs. Pyramid Sharpening on a Straight Razor

I’ve been a regular on the Straight Razor Forums lately, and I’ve been finding success with my razor (finally! A special shout out to JimmyHAD from SRP!) As an experienced sharpener of reed knives, kitchen knives, scissors, and even dental tools, I have always used a progressive method of sharpening. Using Shaptons, this makes sense because Shaptons are built with that in mind – they are meant to go to #30,000 (even if you don’t, that’s ok, though).

Shaptons and progressive sharpening  work on the idea that more scratch marks are added to an edge as the grit gets finer, eventually adding so many uniform and densely packed scratches that they form a mirror finish, and a very nice edge. So, if you begin shaping your blade with a coarse stone, say, a #320, or #1,000 grit, and then go to the #2k, 5K, 8K, 15K and finally the 30K Professional stones, the surface of the edge will have scratches that make a .5 micron finish. Sounds great.

But pyramid sharpening has been taking hold of my brain. As I explained in my Sharpening Epiphany entry, the pyramid method of sharpening eliminates the peaks formed by the previous stone’s scratches, essentially evening out the grooves to make a smooth edge. If you follow the same stone progression as above, the real final stone would be the 15K, followed by just a few passes on the 30K to even out the peaks formed by the 15K.

The interesting part begins here. I think the way you get to 15K, or your second to last stone doesn’t really matter much. I would guess that the pyramid is a little slower than the progressive  in getting there because you are going back and forth between stones – whatever. It is the last few 2 that will determine the final shaving edge, and are therefore, the most important.

On the pyramid sharpening, the 30K evens out the peaks left from the 15K, really leaving an even 15K edge, but in progressive sharpening, you will have a “straight” 30K edge, which sounds a little better to me. But the catch is that if you take enough (or too many) passes on the 30K, you will eventually create 30K peaks and valleys, which will be relatively smaller than the 15K peaks and valleys (about 1/2 the size in theory), but it will still be jagged. By using the pyramid, the smoother final 15K edge may be “thicker” and less refined than a 30K progressive edge that is jagged, but more refined.

So, I now come to the conclusion about which is better: It depends.

That is the answer to every sharpening question, BTW. : ) Here’s why: The pyramid, as explained, is a “safer” approach to a smooth edge without peaks. However it doesn’t mean that progressive is evil. What makes pyramid more appealing is the fact that you can easily overdo it on the 30K (or final stone) by using the progressive method. A good sharpener can compensate with the progressive method by taking fewer finishing strokes. This is where you can borrow from the pyramid, say 5 passes after the 15K. (This is borrowed from the SRP Wiki, and is meant for the Norton stones, but I don’t quite know if this same ratio is ideal for Shaptons glass or pro.)

I hope this helps show those who prefer one method over the other how they can both work, and why they both work.

So the argument continues. Is it coke, pepsi, or whichever is on sale this week?

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