We all have ‘side projects’ which sometimes get realized but more often than not, get shelved as ‘real projects’ take priority. Fabricating my own bike frame had been on the boards for years and when my last bike got stolen, this project got bumped up in the priority list. Fabricating a custom bike frame is an endeavor of precision, so I definitely took my time with the steep learning curve – from the mitering of tubes to the welding of thin-walled tubing.
The frame geometry was ‘averaged’ from a few other frames I liked and designed in Rhino. Tube miters were visualized precisely how they were to be placed in the Bridgeport (I have no special frame-building fixtures).. Before welding the actual pieces, many practice welds were done experimenting with different tungsten electrodes, different amperages, different filler metals, etc. Once a comfortable balance was set, the actual welding of the frame went relatively quickly.
Tubing was straight gauge 4130. Filler rod was .035 Weld-Mold 880 (a high strength and high ductility stainless filler). Powder-coat is a textured grey. The bike build itself tries to stay clean, simple and utilitarian.