Plomb 1130 7C: what kind of steel?

[kingcole]

Hi all. I'm new here, and am trying to get some info on the kind(s) of tool steel Plomb would have used in a Plomb 1130 wrench (9/16 and 5/8). I'm hoping someone can point me in the general direction of the type of steel this wrench would have been made from. The wrench is ruined, but I'm considering making something else from what's left, if the steel is right.

It's marked "7C," which I believe means it was made in 1937.

Is there anything else anyone can tell me about this tool? It was my late father's, and I'd love to know as much about it as possible.

Thanks very much for any help you can provide.

Jon

[rusty]

It is hard to tell, most of the tool makers were offering alloy steel tools by the mid 20's, but the alloys varied wildly, Billings was using Chrome-Moly, Others were using Chrome Manganese, Still others thought Vanadium Steels were better for tools, and 1930 is right in the middle of the fight...

Plus, nearly all the companies still offered the plain carbon steel tools for low cost alternatives...

AA Notes references to Plomb using tungsten steel , and moly steels in early tools....

[kingcole]

That's a great start - thanks!

Is there a way to test (spark test? or . . .?) to narrow it down a little?

I really appreciate the help. Thanks!