Thread: HHT? a question again?

I have honed quite a few modern silver steel razors (say from the 1940s onwards for arguments sake) and have found that more laps on the hone are necessary for around 75% of them. Some were much harder to hone, ie took longer. The others I couldn't detect much of a difference on.

Below are some Rockwell Hardness ratings - these were gathered form manufacturers info, from people who have had their razors tested for some strange reason and from some modern makers who have or have access to testing machines:

G&F Timor (new): 56/57 HRC
Wade & Butcher: 58/59 HRC
Herder: 59 HRC
Case: 60/61 HRC
Puma: 61/62 HRC
Older TIs: 62 HRC
Hart: 63 HRC
Wacker Damascus: 63 HRC
New TIs: 63/65 HRC
Iwasaki: 64/65 HRC

It must be noted that the test may be one point on either side of the rating, so for those giving just a single figure we either assume that this is the mean figure or take it as one point each side of the given figure.

Personally, from 62 HRC and up I can definitely detect the difference while honing.

Modern silver steel is usually delivered with a quench hardness of 64 - 69 HRC.

But hardness is only one aspect: the fineness of the grain composition, retained austenite and a lot of other things come into play, it's definitely not all about the rockwell rating.

Regards,
Neil