Backstop Rapid Prototyping

On my single speed bike, I run front and rear brakes. However the frame doesn’t have cable routing bosses on the top tube. Right now I just have the cable housing zip-tied to the frame. This isn’t a very elegant solution and I wanted to improve it.

Problem Solvers makes a nice clamp that will route two cables. Unfortunately they don’t make them to fit my 1.0 inch top tube. Carnegie Mellon has a 3D printer and I had always wanted to experiment with rapid prototyping parts. It is very easy to design a part in Solidworks and then export it to the 3D printer. I thought I could design and fabricate something to fit my need.

backstop_small
Versions 1 through 5, left to right.

After five iterations I got down to the design that I wanted. I had to get the inside clamping diameter set, the hinge mechanism working cleanly, and the clamp bolt threads strengthened. At this point I would like to work to create machining specifications to have parts CNC’d. However, unlike the iterative process of the 3D printer, creating a CNC layout will be a big hurdle that I’ll have to overcome before I see any additional progress towards my goal. So, I don’t know that I’ll have any more time to devote to this project. So, for now its moth-balled but I may come back to it. Here are my Solidworks files for anyone who want to take this project over.


Rendering of version 5.


Solidworks files

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