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Wed Oct 09 2024
- Brush: Zenith – 506 N XS (extra soft horse)
- Razor: Böker – 14er (8/8", extra hollow, carbon steel, square point)
- Lather: Mäurer & Wirtz – Tabac Original
- Post Shave: Mäurer & Wirtz – Tabac Original
- Fragrance: Mäurer & Wirtz – Tabac Original
This concludes a week of shaves with 14-type razors with a stellar shave. After a lacklustre bout with the factory edge, I refreshed the edge, and there it is, that smooth, soft extra hollow feeling. This modern 14 is really on par with the Fili, Frio, and Henckels originals. I'm really looking forward to comparing this to the Moarteen soon.
Zenith extra soft horse ++;
This modern 14 is really on par with the Fili, Frio, and Henckels originals
I think it is all about geometry. I measured the bevel angle on the Gen 1 Fili, River Razors 14, Koraat 14-2.0, and Frio 14. All razors have bevel angles at ~15.5 degrees. I have measured other hollow ground razors that I have and none, except my cherished MK 31 Söderfors Extra Specialstål, have bevel angles equal to or less than this. The "better shaving" razors are all close though. Sadly, my River Razors 6/8 has a bevel angle of 19.2 degrees.
I think it is all about geometry.
that would make a lot of sense
Sadly, my River Razors 6/8 has a bevel angle of 19.2 degrees.
Does that mean that it's not a favourite?
Sadly, yes. I’ve known for a long time that typical razor bevel angles fall between 15 and 20 degrees. I tinkered with this, myself, a couple of years ago. I reduced the spine width on my Gold Dollar to change the sharpened bevel angle from just over 20 degrees to 18 degrees. Took a long time. The feel of the razor improved considerably.
That's a bummer.
I don't want to imagine how much time and effort it took to whittle down the spine enough to make a meaningful change in bevel angle 😅 .
Btw, I now want to measure my 17. I have a feeling it may have a blunter angle than my other razors, but it still shaves great. I need to double check my assumptions here.
Btw, I determine the bevel angle by just calculating the sharpening angle and doubling it. On all the razors I’ve seen, the sharpening angle falls well within the range where the small angle approximation for sine works. Typically, I just do the trig in my head.
Once I started paying attention to sharpening geometry, I started to realize why I like certain razors so much. I would be very interested in your experience on this as well. I’ve realized the ways in which I adapt to razors with wider bevel angles and this tips me off to actually measure them.
I'm not sure I follow. I'd have just measured the spine thickness t at the place of hone wear, and the width b from edge to spine hone wear and computed the bevel angle as α= 2 arc sin(b/(2w)), just as the central angle of an isosceles triangle . Is the sharpening angle β = α/2? in that case, I agree that β ≈ sin(β), certainly at the precision I'll have measuring t, and b.
Yes, that’s the sharpening angle. The bevel is formed by laying the razor on the stone at the spine and edge. The razor is sharpened by removing material (abrading) until the centerline from the spine through the edge intersects with the stone’s surface. For a razor, that angle is typically less than ten degrees and within the small angle approximation range. If I have my phone handy, I just use the calculator. Much more convenient than a slide rule :)
For the approximation to become useful, we just need to start thinking of bevel angles in units of radians now 😄
Already there, except I think in terms of sharpening angle and save the multiplication step. Since you have a penchant for maths, you'll be soon to follow :)
