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Thoughts on optimal scale thickness?

Hi All,
I had a recent opportunity to pick up a few knife handle blanks recently - they are 0.5” thick. I will be cutting them down soon on a bandsaw to try and get them down to a width more suited for straight razor scales. This brought up the question “What thickness should I aim for?” In my collection I have scales ranging from 1-5mm (0.04”-0.2”) - in general I prefer 3mm and thinner for horn, wood and plastic. For scales made to date I have tended towards <3mm for lighter blades (e.g. 5/8 hollows) and only gone thicker when I had thicker blanks and wanted mass (e.g. for a 7/8 wedge). But I do seem to lose flex over 3mm. I am curious what thickness other scale makers aim for.
Caveats:
1) For the purposes of this question I am assuming a uniform thickness other than filleting the edges. Of course a scale with a domed outwards facing surface will flex more than one that is uniform thickness.
2) And yeah, I know when I cut the wood some of the material will disappear into the bandsaw. In addition the surface I get will need sanding to remove the marks of the blade. But I’m still thinking that if I cut into 3mm (1/8”) slices the 3rd slice will be a bit too thick. But going to 4 slices will likely leave me <2mm.

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PS I actually got the 3 pieces of wood with price tags, plus the pen blank for $15, which to me seemed like a pretty good price. Not sure if the pen blank can be made into scales, but no harm in trying!
 
Other than aesthetics, for me the two most important things about the size of scales is the width near the pivot when the SR is opened 270° and the balance point of the SR when opened 180°.

The width near the pivot needs to be narrow enough to be comfortable to shave with. The opened razor needs to balance fairly close to the pivot pin.

The actual thickness of the scales does not affect a SR's shaving comfort, however the overall mass of the scales will affect the balance point. One of my SR's has scales about 1mm thick but they are fitted with a lead wedge which helps locate the balance point very near the pivot.
 
You want to be somewhere between 0.09 and 0.110 inches thickness for scales (2.2mm to 2.7mm) depending on material. Thinner for more brittle materials like bone, ivory, some woods, etc. Horn can be left thicker but I tend to make mine a bit thinner than the vintage scales I've measured. You really want to have a good chamfer all around the edge and blend it in well, it will make a thicker scale appear thinner and more elegant. Nothing worse than clunky thick scales or scales which are just slabbed out with no shaping. The older razor makers really had it nailed for scales so I suggest measuring and looking at some old scales if you have any to hand, a lot of the modern scales, especially in horn and bone are comedically thick (Wacker, Thiers Issard). Wacker especially since they pin the razor absurdly deep at the pivot too. Absolutely horrendous things. I don't tend to make thicker scales for bigger razors, there's little point trying to balance a large blade by beefing up the scales imo, all you do is reduce the ability of the scale to flex which could cause issues with more brittle materials. Horn, bone, wood are never going to be dense enough to offset a large blade, especially if it is a heavier grind. You'd be better off using a metal wedge for balancing (lead/pewter/brass/etc).
 
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How large are those slabs in the pic btw? They look kinda short but could just be the camera.

Each stack had 2 slabs nominal 0.5” thick (the Orange Osage was closer to 5/8”) and then nominally 6”x2” . The walnut piece was 2”x2”x6”, I turned part of it into a brush handle earlier this week.
 
I have a set of ivory scales that are right at 1mm with the calipers. Scary thin. I kind of like an 1/8th inch blank, because even with a good chamfer, they'll sit upright on the shelf. Although I always lap them down closer to 3/32. Which I think is a little over 2mm. Any thicker than 1/8 and they just look wrong to me. I've never tried to make a quarter or half round scale like some of the one you see from around 1900 with bolsters. I guess those are somewhat thicker at the center but I'm not a fan of that look either.
 
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