Henckels Friodur won't hold an edge

I have a Henckels Friodur 72 1/2 that I have been struggling with for a while. I tried my best to hone it but couldn't get it to take a decent edge. I sent it to Lynn and got it back with a very good edge that deteriorated after the first shave. I touched it up a little and got it back to very good, but it starts pulling hair the next shave and can't even complete one shave with comfort and close cuts. I'm about ready to sell it, throw it away or use it as a box cutter. The edge never gets what I would call "excellent," even when it came back from SRD.

To rule out variables, I have quite a few razors that I have honed and maintain/strop that shave very well. Having so many good ones makes me think it's the razor. I've heard great things about these razors, so far it's been a sore disappointment. I've thought about adding tape to the spine to strengthen the edge, but haven't tried that yet. I can't understand why the edge won't get any better at the factory angle.

Do you have any other razors that do hold an edge? If you have other razors that do hold an edge, then your stropping is not the problem.

Yes I do, I have several that I have shaved with dozens of times with no noticeable deterioration of the edges. These include two King Pelicans, an unnamed German silver steel, W&B, Heljestrand, Filarmonica, Dubl Duck, & Burnell.

I do have a fridour inox... it hold edge vey well, and for being Inox, it also catch a very sharp edge... i have used it like 4 times since i hones.. i'll use it a few more times and report back just in case.

I apologize for not paying heed to the second half of your original post. I read it, but it didn't sink in. Given that you are getting good shaves with your other razor, I have no explanation for your trouble. I suppose such a thing as a dud Friodur might exist.

Well I have several of those. They are all pretty great razors. I have one that was just an absolute turd to get homed the first time. There were two tin spots on the bevel that would chip every time it got close to finished on the hones, I would back up and try again. Eventually the problem did resolve itself. I bought the razor NOS from a very reputable vendor. I have many Henckels and only one that was less than stellar. It may be that your razor had a rough experience somewhere in its life. What era is it? Pic?

I would do just as you are thinking. Tape the spine. I find that anytime I'm having trouble getting a razor to hold an edge, tape helps. It's a slight adjustment that you should not hesitate to use if the edge isn't holding. If you've been grinding away trying to set a bevel and can't seem to get it, tape might be your answer. If one layer doesn't do it, two or even three might. Rule out other potential problems but if nothing else, try tape.

Is there any discoloration in the blade that might indicate a loss of temper? They may have put out good razors, but that doesn't mean the people that owned them knew what they were doing....

Do you have a microscope to take a look at the edge?
I have one or 2 razors whose spine I tend to raise slightly off the strop towards the end of a stroke on the strop. Has to do with the shape of the tang I guess.

Some pictures would be nice of the blade faces depicting bevels and honeware....
There are several problems that may manifest themselves as you described.

1.If the sharpening angle is too small that might be a reason for edge deterioration trough microchiping - a sighn of this is pronounced honeware and wide bevels....you solve this by adding 1-2-3 layers of tape to obtain a corect angle and a bevel width of about 0,5mm.

2.A bad temper could also be a reason ... or a bad restore on high speed tools that could have overheated the blade....
- In this case try "snaping" your finger nail or thumb over the tip of the blade and listen to the vibration/sound it produces....a high pitch sound indicates tension in the steel matrix and can corelate to a god temper...a low pitch sound like tin - as in the tin of a can indicates low tension and a los of temper.
You can also make sence of this on how the blade "sings" when shaving.
Again adding 1-2or even 3 layers of tape on the spine...this will put more metal behind the edge and possibly increase edge resistance if the temper is not totaly toast...ths is when you might consider a letter opener.

3.If it would have been a carbon steel blade an acid bath would show the delimitation between hardened steel and softer steel....harder steel gets much darker after an acid bath then softer steel...it's all about the cristaline structure the steel gets when austenized...BCC and FCC...these two cristaline structures react diffrently to acid...one beeing more resistant then the other.
Long story short same as the hamon on a japanese blade...diffrences in temper on carbon steel blades can be seen sometimes after an acid bath.

My 2 cents...hope it helps.

The razor isn't hollow enough to make much noise when shaving, it's an old 72 1/2 with yellow scales. The blade does have heavy hone wear but the bevel remains what I would consider normal. The blade looks perfectly even-colored. I don't have a microscope, but I believe that Lynn straightened out the hone wear and bevel when I sent it to him. I'll try the tape to strengthen the edge. If it continues to suck, I'll try another 72 1/2.