Process: Braze-ons and seat tube slotting

Before the frame is fillet brazed we drill the bottle holes and also cut the slot into the rear of the seat tube. Bottle boss holes are drilled using a jig, which ensures that the holes are located the correct distance from the bottom bracket and they are in the centre of the tube. We then cut the seat tube slot using a slitting saw in the milling machine; again this ensures a very accurate cut in the tube centre. We then mark on all the tubes where the cable guides, sti guides, and any other bosses need to be located.

Finally we silver braze the bosses/cable guides etc on to each tube and once cooled put the tubes into the soak tank to wash away residual flux. The reason we do all the braze-ons before we fillet braze the tubes together is that if they are done at the end they will cause the frame to distort due to the heating.

Other processes


Headtube & BB Prep


Braze-ons and seat tube slotting

Fillet Brazing


Hand finishing