Thread: A response to my questions from Heribert Wacker

I am always happier if I get a razor advertised as 5/8 and it turns out to be 11/16s. I don't know if that is just me or if it is a USA thing. The old bigger is better syndrome.

Originally Posted by Spect

Woah! Anyone else look at the BS1407's hardness? 64 rhc. You could be seeing micro-chipping pretty quick when the steel is that brittle.

Just because that type of steel CAN be hardened to that level doesn't mean it has to be. It depends on the formula used to temper the metal. The hardness is always adjusted with the tempering process to make sure it is only as hard as it needs to be and isn't brittle.

I'm not sure this is the same thing. 1970 is way late to apply to most straight razors. I have an old Solingen blade from a 7-day set that is quite old that is labeled "Feinster Silberstahl" i.e. "Finest Silver-steel." The term seems to have been used long before 1970. I have a book somewhere that discusses this a bit in relation to razors. I'll hunt it down and see if the waters can be even further muddied!

Originally Posted by John Crowley

I have been researching a little more and it seems that silver steel is a specialty item not produced in great quantity any more. The technical specification for modern silver steel dates back to 1970.

Genuine BS1407 Silver Steel
Silver Steel is a versatile high carbon tool steel is ground to very close tolerances. It is so called because of its highly polished appearance created by the extremely fine surface finish. The high carbon content of this BS1407 silver steel means that it can be hardened to give considerable wear resistance and the chromium content increases strength and hardenability. It is readily machinable as supplied in the spheroidised annealed condition. The material as delivered shall have a hardness of not more than 285HB when measured in accordance with BS240*

It appears that BS1407 is roughly the equivilant of SAE O-1 and is only made in the UK:

From: Technical information on steel shafts for DIY'ers.
There are other specialist shafting steels that can be bought usually described as "ground" or "precision ground" bar with even tighter tolerances (+0,-0.015 mm) and better surface finish (0.6 microns) than standard bright bar. One of the most commonly available of these in the UK is "Silver Steel" or more precisely high carbon bright steel to BS1407. This is commonly available in short lengths and is suitable for hardening (it contains about 1.1% carbon) but is also considerably stronger than mild steel in its unhardened supplied state and can often be used as bought. (I understand UK Silver Steel is approximately equivalent to US ground tool steel SAE 0-1.)

Originally Posted by LawsonStone

I'm not sure this is the same thing. 1970 is way late to apply to most straight razors.

More like 1870

Thread, thread.... I meant to say 'thread," not "link." Sorry about that.