Process: Headtube & BB Prep
Once the tubes have been selected the first job is to prepare the headtube and bottom bracket. Firstly the headtube is cut to length in the lathe this ensures that the exact length is accurate and also that the faces of the head tube are completely parallel. At this time we also use the lathe to ensure the BB is parallel as this is crucial to the correct frame set up in the jig.
Next we drill gas holes in the headutbe and the bottom bracket, which allows the hot gases to escape during brazing. The holes also mean that when we soak the frame the water can enter each tube so that any residual brazing flux is washed out. Finally we use the gas holes to treat the inside of the frame with a rust protection chemical so that it is corrosion resistant.