With the collapse of machine tool industries in the US during the I980's, special purpose machines such as the horizontal mill at right, shown cutting a curved miterjoint, became less readily available (except from factory closing auctions). These kinds of machines are essential for quick prototyping ofbikes to fulfill evolving community needs. The disappearance ofsuch hardware burdens local small-scale workbike builders, but their primary burden is the general high cost ofbicycle-building tools. Custom-made bikes are usually made for the reasonably well-funded, and so the tools are pricedfor recreation cycling, not for more practical vehicles. One solution is to create new tooling arrangements. VanderTuin has spent years researching inexpensive tube bending, cutting and welding. Top left, Dick Ryan of Ryan Recumbents demonstrates how a standard industry jig (a design frame that holds tubes in place for welding) is used. A jig's plate is cut with expensive equipment out of solid steel, putting it out of range of producersfor a small local market. Instead VanderTuin builds his own jigs (directly left) by cutting rectangular steel tubes and welding them together. He then places it on any flat surface, such as this door, to do a preliminary, or tack, weld. Not only are these light, cheap, andjust as good as the solid plates: they allow one bench to produce any model with a simple change of jig. In either case, bicycles are then made true with various inexpensive straightening devices, such as the one used in the bottom photo forforks. technology is adaptable, so bikes find their way into a broad range of activities. Vander Tuin would like to see communities in the US develop this kind of technical understanding and appreciation of transport diversity. Large-scale bike manufacturers have failed to understand workbike technology, perhaps because a bike’s design must relate to some specific social role, a situation which defies easy national marketing. VanderTuin designs and prototypes with community-sized intermediate scale production in mind. For small- businesses the key is to facilitate low capital start-up of local bike construction. For example, a big expense in building bicycles is the almost immobile flat steel table “jig” (the frame used for holding the bicycle tubing in one plane for welding, see top two photos). Instead of using these, VanderTuin makes jigs Page 16 Rain Winter/Spring 1992 Volume XIV, Number 2
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