"hearth" is perhaps a colloquialism. witcomb lightweight cycles had that set-up. those are firebricks and they serve to save any lost heat - it's refracted off the brick surfaces and keeps the joint at a better working temperature. it's hardly old-tech. their frames are better for using that method rather than free-brazing in a park stand or in a fixture. e-RICHIE chester, ct
Chuck Schmidt <chuckschmidt@earthlink.net> writes:
Frank Knox wrote:
>
> Thanks for your reply. I don't know as much as I would like to know
about
> this. I'll do a search for open hearth brazing.
Frank, they have been doing it this way since 1946!!! If the bikes were no good they wouldn't still be in business. Like I mentioned, I love the 1959 Mercian Vigorelli Superlight road/track that I ride all the time, and it looks like it has suffered plenty of abuse from some of its previous owners and is still in one piece.
Me at the San Diego vintage ride:
http://www.fixedgeargallery.com/
Chuck Schmidt
South Pasadena, Southern California