A Comparison of Several Manufactured Blades


Vintage NOS Gillette blue blade (E3, manufactured third quarter of 1959)


Vintage NOS Gillette blue blade (E3, manufactured third quarter of 1959)


Kai/Miltex disposable scalpel blade


Kai/Miltex disposable scalpel blade


Modern Gillette Astra Stainless DE razor blade


Modern Gillette Astra Stainless DE razor blade


OLFA disposable snap-blade knife


OLFA disposable snap-blade knife

All four examples have a cutting edge with a width less than 200nm, although the final bevel angle varies from 21 degrees for the Blue Blade to more than 40 degrees for the Olfa blade.   The Olfa blade also has a small burr on the edge which reduces the effective keenness.


Edge Burr (foil or wire) on the Olfa snap blade.

At minimum, these examples demonstrate the scale at which we need to resolve and image features is well under one micron.

With our definitions of Keen and Sharp we can see that all blades have similar keenness, but the razor blades are sharper than the scalpel and utility blades.  The images below demonstrate that the Feather Super Pro Artist Club blade is much keener than other manufactured blades, but is not nearly as sharp as a conventional straight razor.


Cross-section of a Feather Super Pro Artist Club blade, often considered to be the “sharpest” commercial razor blade. The blade is coated with a fluoropolymer that is removed with the first use. The Apex width is approximately 50nm, keener than any of the commercial blades shown above. The width at 3 microns is 1.4 microns, due to the 19 degree final bevel angle.


Cross-section measurements of a conventional straight razor, honed to a 16k whetstone, prior to stropping. The edge width is on the order of 100nm, less keen than the Feather Super Pro; however, the width at 3 microns is only 1.05 microns, significantly Sharper than the Feather blade.


9 responses to “A Comparison of Several Manufactured Blades

  1. It does appear that the last micron or so is at a steeper angle than 19° – and it doesn’t look like convexing but a separate tiny bevel. How they are putting that last little bit on the very edge would be interesting to know.


  2. Ah, must be the scale I’m not used to. At that level it sure looks like a tiny microbevel! These blades are likely finished in strip form, right? So they must be doing a power stropping or brushing of some sort. Sure would be interesting to see the factory floor and have access to the processes used.


  3. I was in Japan, so I got my wife to purchase me a case of Feather Super Pro blades off of amazon.jp. I had my first shave with them last night, and it was a great experience. Feels similar to a straight razor using your progression, right after refreshing.


  4. Great work Todd! I have found that on some brands of these blades, they need to be stropped or micro-beveled to get them to cutting well, and it can vary from blade to blade even within brands. Take care!


  5. Love this post, thanks!
    Too see the plastic coating in the section makes me wonder how the blade can cut hair.
    Perhaps the plastic was deformed.
    In the picture with section cut the blade width 3 micron from the apex is doubled with the plastic.
    And the apex itself is totally covered in plastic.
    How can the blade penetrate and cut hair with this coating?


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