The dish in the seat stay is a scrap of seat tube, nickel-silvered in place, and then silvered onto the side of the seat cluster. There are still some learning gouges visible through the paint, and some gaps along the shoreline, but next time all will be smoother, maybe... All the joints were pinned and silver soldered following Richard Sachs excellent photo examples... BTW this is a steel seat post, a Campy Centaur, and it fit without reaming, though really snug.