The straight razor that can't cut test media

[Jan]

Mr. Mark, I am sorry I cannot shed light on properties of straight razors.
 
Only recently I received an old, totally destroyed German straight razor. The guru of the local straight razor forum told me that it was a high quality product (N. & H. Clauberg, Gold Fish, Solingen). The handle is of horn, decorated with silver ornaments. The guru spoke of it as an "old lady".
 
I decided to re-purpose the razor torso and shaped it to a letter knife (letter opener). Because the carbon steel is really very hard I used my low speed, water cooled fine diamond wheel. Re-shaping of the straight razor impressed me. It is very fine steel and the spine is quite robust.

The picture at the bottom shows the degrees of hollowness of the blade.

Jan

   
   
   

[grepper]

Very nice Mr. Jan! Most folks would have thrown that away but with a bit of work you repurposed it and gave a beautiful old tool a new lease on life.

[Jan]

Thank you Mr. Grepper! You know I'm still out of the old school and it takes me a long time to throw something away. It's a real pleasure to hold such an old beautiful tool in hand.
 
Jan

[Bud]

That is a nice looking piece Mr. Jan! Do you think, in it's new shape that it could still be used for shaving assuming it were sharpened for the task? We all know the general shape of a straight razor so I guess I'm asking if that shape is critical for straight razor users.

[Jan]

Thank you Mr. Bud.    I am not a straight razor user, but yes, I think that the shape of the blade cross section is crucial for correct razor functionality.

My razor torso was originally high quality straight razor with a blade width of ½ " and after repurposing it the width was reduced below 3/8". Now the letter opener bites my finger nail, but I am afraid that it is not sharp and flexible enough for good shaving.
 
First reason why I did not try to reshape it into narrower straight razor was the fact that the original radius of bevel curvature was much, much smaller than the one of my diamond wheel (10").

The second reason was the fact that I do not have fine enough water stones for final razor sharpening. They use 1k, 3k and 8k grit and more. Such stones are too expensive for experimenting.
 
Regards
Jan

[Jan]

Just out of curiosity I am attaching a picture of my disassembled E.Weck & Co. Army Corp Medical/Surgical Sextoblade Straight Razor. This was used as prep razor by military surgeons.

I am going to hone the blade because I do not have a spare one. I have just measured the bevel angles. The primary bevel has 5 degrees per side and the secondary bevel has 10 degrees per side.


Jan

   

[Bud]

Thank you Mr. Jan. It's always good to come here and learn something new.

[Mark Reich]

That is really a cool razor, Mr. Jan! It will be very interesting to learn how you'll hone it. If I understand, it has an edge bevel of 10°/side? 20° inclusive seems like the obtuse limit for razors. Straight razors can be quite a bit skinnier, but I think that's consistent with factory razor blades.

I've been super busy lately, but last week I did find an older stainless steel Double Duck Goldedge. They're made in Solingen Germany, and it is in really nice shape. I'd say it's a 5/8, 1/1 hollow (Thanks for the diagram Mr. Jan!). It sure honed up nice and quickly, and I'm very happy with it.

I also broke down and watched a bunch of Youtube videos to make sure I was in the ballpark with my bevel setting, honing and maintenance. After watching a couple dozen of the best videos I could find, I was satisfied that I've been playing by the rules, and this really isn't any big deal.

I did learn some good things that I wasn't sure about, but for the most part it's actually simpler than I thought. For one thing, maintaining a straight razor goes pretty much exactly like I described. It simply stays about the same sharpness, but for much longer than I thought. I said I take mine to the stones a couple times/year, and it seems like that is probably enough for guys who shave every day. I probably heard the "couple times/year" suggestion, and went with that.

Another thing that I confirmed is that your face will surely tell you how well you're maintaining your razor. In fact, the Double Duck got sharper than I'm used to, and I took off a little too much skin on one pass. Not a big deal. Kinda looked like I got a big rug burn (in an odd place), bad enough to cause epidermal leakage, but it stopped leaking and went away quickly.

The problem I'm finding is that the media is clearly too tough for the straight razors I have. The new DD didn't stand a chance. I didn't get a single measurement out of it.

From now on I will mark the blade and try to get a measurement. If it looks like it's going to be >75 BESS, I'll examine that spot for edge failure. I'm pretty sure any decent job of honing should yield BESS 50 if it doesn't distort the edge. The (more or less) tried and true hanging hair tests may be more appropriate IMHO.

[Jan]

Yes Mr. Mark, the secondary bevel has 20⁰ inclusive.

I used the Lansky clamp as a jig for my Tormek. Using my standard kitchen knife procedure for sharpening and honing I got BESS score 90. Not a brilliant result, but I used standard 220 grit stone graded fine to some 1000 grit and a standard honing compound with 3-5 microns alumina grains.
 
Jan
   
   

[EOU]

We appreciate that you gentlemen are having a look at this. While thousands of edges that measure 10 - 50 BESS have been measured for years without problem, many straight edge sharpeners don't seem to enjoy this success. Undoubtedly, the geometry/sharpening techniques being applied lend themselves to producing very delicate edges. These are edges that won't withstand a few tens of grams force before folding. These sorts of edges may be just what the Dr. ordered for shaving softened whiskers but not for severing BESS test media. That seems clear now. Our advice is simply not to use our instruments for testing straight edge razors unless you feel that you have devised a sharpening means that produces both a sharp and more structurally sound edge. This seems as if it would be quite possible in that Feather DE blades measure around 25 and microtomes measure 10 and we've never heard of a report, nor witnessed ourselves,  either denting or folding during the measurement process with these edges. Measurements of BESS 25 involve applying little more  force than simply touching the edge to the test media.

In the final analysis, we say "if it ain't broke don't fix it". If your straight edge sharpening technique seems to serve the designed purpose well, we wouldn't advise changing it just so that you can use one of instruments to gauge your sharpening success.