PJ1 (part2)
Main tubes cut, mitred, cleaned and set up in the jig. A small amount of flux is added to each joint (the red stuff) and small ‘tack’ brazes are laid down to hold the frame together. Normally I tack at 6, 12, 3 and 9 o’clock. The order of these tacks are quite important. When you add any kind of heat to the tubes they want to move, expand, twist and so on. In order to keep the frame as straight as possible I add the tacks in order that each subsequent tack brings the frame back into alignment.
Once the frame is all tacked, it’s taken out of the jig and onto the alignment table to make sure it’s still straight. If it needs tweaked then we do that at this stage.
Here’s a close up of the downtube/headtube junction about to get tacked.
Currently playing in iTunes: Wild Mountain Berries by Kelly Hogan & The Pine Valley…
