At 13:31 2/16/2001 -0800, Stockwell, Brad wrote:
><snip>
> In '78 when I repainted my 1971 Zeus Competition (built with 3 main tubes
>531), I noted that once the frame had been stripped I could just make out a
>faintly engraved 'REYNOLDS 531 DB' marking on the underside of the downtube
>near where the shifters would be mounted.
>
> Presumably Reynolds tubes are always marked this way? Do other types of
>tubing (at least the fancy ones) do this also?
Reynolds fork blades often show the brand mark on the outside of the blade;
on some old Paramounts it could be seen through the thin silver paint.
I've seen Falck tubing marks on the downtube, above the downtube shifter boss. Looks a bit like an equal-armed hollow T, or a 3-lobed Rootes blower, inside a circle.
The Columbus stamp looks like the logo, and is found on the same place. dirty birdie :-) in oval.
The reason it is there, I am told, is that the two butts on the down tube are different lengths, and this gives the frame builder a signal on which is the long end that can be trimmed to fit the design length.