On Wed, 1 Jun 2011 11:05:43 +0000 (UTC), xpzzzz wrote:

On Wed, 01 Jun 2011 16:33:43 +0700, john B. wrote:

I'm in the process of rebuilding a bicycle frame and am left with some
minor dings and scratches which I want to fill and fair. The tubes are
rather remarkably thin and I really do not want to use a file to clean
them up. My idea is to use lead solder as a filler and my problem is
that I have no idea what to use for flux.

The reason for using a metal filler is that the frame will eventually be
powder coated and the preparation used here is a good glass bead
blasting and I don't think that conventional painting fillers would
stand that, or the high temperature baking.

There are special epoxy fillers for powder-coating - temperature-
resistant and electrically conductive.

I'd leave the dings and just coat over them; if they are big enough to be
a structural problem you want to notice that, not hide it.

And big enough can be quite small - think crack-initiation...

Something else you might consider is baking-soda blasting.


It is not something to think about. The only place in that part of the
country that does powder coating used glass beads - take it or leave
it.

I admit that the dings are really too small the worry about but a
couple are, for instance, right in the middle of the top tube and they
sort of stick out like a sore thumb from the shinny polished look of
the rest of that tube.

None of them are serious enough to result in a strength problem but
after exerting considerable efforts I want it to be purty :-)