The lastest project underway at supacustom is a custom bicycle for my girlfriend Renee, this isn’t the first bicycle frame that I have built but it will be the first to carry the “supacustom” brand. It seems lots of readers are curious to know more about what goes into building a bicycle frame, so I’ll try and step through some of the details here on the blog.
First step is to spend some time sorting out the geometry for the bike. So many factors come into play at this point, size of rider, ride and handling qualities, components…lots to consider. For me this process always takes quite a bit of time, I rough the geometry out in 2D and then generate a 3D CAD model of the whole bike. This frame is going to be built into a single speed flat bar road bike, something for Renee to get around town on. The geometry is standard road geometry with a small stretch in the top tube to account for the flat bar setup as opposed to road drops. Next step is to select a tubeset, I opted for US made True Temper Platinum OX tubing from Henry James. The dropouts, BB shell and cable guides are all from Paragon Machine Works – I was super impressed with the quality of both the tubing and the Paragon parts.
With the design complete and all parts laid out ready to go there was nothing left to do but to start cutting tubes, I hand mitre all the joints the old fashioned way, with a hacksaw and a file. The BB shell pictured above needed a drain hole, a round hole seemed a bit dull so I decided to add a special touch for Renee.
Precision in the mitres is critical, I use a program called tubemiter to generate some templates that make the process much easier.
With all the main tubes cut its starting to look like a bicycle. Next step is to Braze the front triangle together, more on that in Part 2.