If you do a lot of cycling, a custom bike frame is highly desirable in order to have the right fit for your body size and posture. However, commissioning a professional framebuilder can be very expensive, and making it yourself requires an upfront investment in welding tools and rigging that you'll likely use only once.
Andrew Leinonen set himself the challenge to make a bike frame without the upfront investment by involving 3D Printing in the process. As Andrew explains: "The process that I came up with takes advantage of the growing availability and affordability of CAD and 3D printing to allow people to build themselves a unique custom bicycle with unparalleled design flexibility".
Another benefit is a lower material cost as off-the-shelf aluminium or carbon fibre tubes can be used for most of the frame structure. Andrew's goal was "to shift away from being restricted by the materials required by the tools, and instead enable you to realize your personal creative vision for what you want your bike to be".
Using his personal 3D Printer, Andrew created lugs that hold the frame together at precisely the angles required. This proved rigid enough that a jig wasn't required for the next stages of the process when epoxy and carbon fibre are applied to solidify and strengthen the frame. 3D Printed molds were also used to compact the carbon fibre as it sets to achieve a really smooth finish.
The complete project requires a considerable amount of work, but it's great to see how 3D Printing has simplified the process and hopefully made it accessible to more people. If this looks like the summer project for you, check out the complete step by step guide on Instructables.