jkn wrote:

Yes, but I can arrange the clamp to be compatible with the bikes I'm
going to be using it on...

Are you going to make the clamp too? If not, then Park Tool have some decent
clamps for sale separately. I'd be tempted to clamp onto the seat post, rather
than the frame in any event.

--
Nige Danton
email: swop the obvious for g_m_a_i_l

Hi all
Thanks for all the comments - I've been away for a few days and
haven't had chance to reply. You've given me some useful things to be
researching a little further.

I did know about the Park clamps but wasn't sure if you could get them
separately over this side of the pond. And it may well be true that a
rotating clamp is not as useful as I'd like to imagine it is. I'm
going to chase sown the scaff pole and also the padded plywood
approach. A nice 'getting-towards'winter' project...

Thanks again
J^n