Originally, frames were constructed with traditional bicycle methods of tubes hearth brazed into cast or forged lugs that provided the steering head, bottom bracket etc., that is the joints. With the advent of all welded frames in the 1950s and the availability of home welding kits, frame building became something that could undertaken in the home workshop. (An article by the author on tube bending appeared in MEW issue 146). For the amateur in the home workshop, his 'design' is usually arrived at by propping up the wheels and balancing the engine on a box between them, before shaping the tubes around them. In a way, this is how the professional designer begins, except that while the 'one off' man works with actual components, the professional works with pencil and paper. While this may seem too academic, a properly made drawing will show the true relationship and the correct layout for the important items such as head angle, trail, wheelbase and so on, which will be explained later.
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