Wednesday, November 18, 2009

Bicycle Project 2, day 2

More theory! Some of the finer points of fillet brazing and lug brazing (bronze vs silver bearing alloys) and TIG welding. Even the mechanics behind Oxyacetylene torches, TIG (tungsten inert gas) and PAW (plasma arc welder). And a broad discussion of the various metal types and their properties. Thank goodness I have no plans for frame-building in the future as Dave would have gone into greater depth leaving me fatigued on the details.

Had lunch at an authentic Guatemalan restaurant (very tasty) and shot the breeze over differences between the United States and Australia. Even took a gander at Tucson Mountain National Park on the way back from dropping off a stainless steel plate for laser cutting the downtube name plate. (did you know that stainless steel needs a chromium content of 11% or more to provide an oxide coat that prevents rusting...)

Started work on the frame. Tubing is Kasai (formerly Ishiwata) standard diameter (1” or 25.4mm TT, 1 1/8” or 28.6mm DT) quad-butted 4130. Lugs are stainless Henry James with a standard HJ bottom bracket and Pacenti stainless twin-plate fork crown. Front and rear dropouts are custom made by Bohm from stainless steel plate.

head lugs have already been shaped by Bohemian Bicycles

No comments: