Kurt Sperry wrote:
>
> > Chuck Schmidt wrote:
> > I'd question aluminum cranks being "durable" enough for pro use in the
> > mid 1930s to the mid 1950s in the big tours of those periods; the TdF,
> > GdI or Vuelta.
>
> Chuck,
>
> I'm not sure why you'd question the durability of- especially '50s
> vintage- Al alloy cranks unless there was a specific design problem.
> The alloys marketed under such names as Dural and particularly
> Hiduminium aka RR55, developed by Rolls Royce for their WWII aero
> engines, available in the '50s were hardly inferior in any way to most
> modern Al alloys. Marketing hyperbole aside, the metallurgy of Al was
> pretty well understood by the close of the second world war.
>
> Kurt Sperry
> Bellingham WA
Kurt, I just repeating what I've read of what the prose used and their reasons for not using alloy stuff in the mid 30s to late 50s. I don't know metallurgy. If you're saying that Aluminum metallurgy was fully understodd by 1945 I'll take your word for it?
Are you suggesting that manufacturing techniques didn't improve from 1935 till _____ (fill in a year)?
Once again Kurt, I'm the only the messenger here, I'm not an expert on alumuinum alloy I'm only repeating what I know were the reasons given by the pros. But yes, I'd have to say there were design problems with the early stuff if it broke more than the stuff nowadays. Wouldn't you?
Chuck Schmidt South Pasadena, Southern California
.