Fascinating story! I had heard rumors about the Ringer - now I know the story. Also funny that of the 6 or 7 Singers that came to Seattle, three now are accounted for. Plus another that used to be owned by George (of Il Vecchio), but then was sold to Grant H.
I don't know much about frame building, but a Singer BB shell is a pretty beefy piece, and I'd repair the frame once more. If it fails, it probably won't hurt anybody. How about silver-brazing the downtube?
Singer paint jobs: Yours seems to have been one of the few outliers. Since the 1970s, Levallois (where the Singer shop is located) has gone from being a center for metalworking (not just bike makers like Singer and Herse, but custom car shops, the Citroen factory across the river, etc.) to a normal suburb. So a lot of suppliers have left - machine shops, chrome platers, painters. I know Singer had problems with paint and chrome, which are farmed out. Pin-striping is especially hard - there just doesn't seem to be anybody in France who can paint long, thin, straight lines with a brush. Having tried it myself, I know I can't. Fortunately, the latest bikes appear to have solved the quality issues. European paint never is quite the same as ours here. Singer charges about $ 150 for a repaint, including sandblasting and decals. Maybe that applies to old Singers only, but in any case, you can only do a decent, not a perfect job, for that money.
Roland Csuka: My friends in Paris all saw him work in the 1990s, up to his death in 1994. In fact, my friend Hervé came into the shop one day, and Ernest was close to tears. Roland had died, and all work had stopped. His health had been declining toward the end. But he definitely did build after 1986.
Jan Heine, Seattle
Vintage Bicycle Quarterly