After making a mess of the second bend on my Columbus Thron chain-stays, I ordered some Columbus Zona MTB S-bend chain-stays from Ceeway. Ceeway didn't have a picture or dimensions or anything for their Zona S-bend stays even though they're offered in 3 bends (MTB, road & cyclocross), so I blindly bought the MTB bend. Turns out they look really nice and are just what I wanted.
To fit a MTB hub between the short stays meant they have to be splayed out quite a bit, this meant removing the pretty little web on the BB Shell so the sockets could be bent and manipulated out.
Then just a bit more fiddling with the stays to get the dropouts in.
The day before I flew to Tassie for an 11 day bike tour, I managed to get the polo frame tacked together. Tris has set up his frame-building stuff out the back of Commuter Cycles so I had to get the jig and all the bits across to Brunswick. It turns out the jig's quite big and only just squeezes into a taxi. Working from 7:30 - 9:00 Tris helped me flux the joins and then stood patiently by as I got the tubes up to temperature and dabbed on some bronze.
An unadulterated Thron stay is at the top, and the curvy Zonas are below.
To fit a MTB hub between the short stays meant they have to be splayed out quite a bit, this meant removing the pretty little web on the BB Shell so the sockets could be bent and manipulated out.
Then just a bit more fiddling with the stays to get the dropouts in.
The day before I flew to Tassie for an 11 day bike tour, I managed to get the polo frame tacked together. Tris has set up his frame-building stuff out the back of Commuter Cycles so I had to get the jig and all the bits across to Brunswick. It turns out the jig's quite big and only just squeezes into a taxi. Working from 7:30 - 9:00 Tris helped me flux the joins and then stood patiently by as I got the tubes up to temperature and dabbed on some bronze.
When it had cooled enough, the moment of truth arrived and it was removed from the jig. It was a fantastic feeling to pull my first frame from the jig, knowing that all the tedious setup and mitring was over and a new bike was only a bit of brazing away. I trial fitted a rear wheel, complete with 26x1.5" tyre but one of the tacks on the BB shell didn't hold. I wired the frame together to close up the gap and went to re-tack but got carried away and ended up completing the first layer of fillet braze on the BB junction.
The frame in its finished shape (obviously with seat-stays to come):
It's surprisingly light considering the straight gauge tubing used (It wouldn't be easy to source butted tubes in such short lengths anyway) and the large tube diameters. The frame is pretty small though, so even though the tubes are relatively heavy per metre, there aren't that many metres of tubing used.
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