A bicycle rack for € 70,-? Self developed, custom fitted, no prior crafts experience, no CAD/CAM, no woodwork skills?
This is the story of how everybody can develop and manufacture a perfectly working product today. Things that were possible only with at least a little investment can be done literally for no money today. The manufacturing cost for this bicycle rear rack was in range with the retail prices of regular racks run from 30 – 150 €. But this one fit the requirements much better than anything on can buy on the market.
This was not my first work, but the one with the most work steps. Therefore, it was impressive, how the construction worked out. The rack is not for heavy weights and not for extreme biking. I would not recommend that for mountain biking. But it holds 5 kilograms (26 pounds), which is enough for 6 bottles of wine or my sports bag or my grocery shopping.
My goal was to have a rear rack that I can easily attach and take off, that helps me to carry minor loads like a sports bag or my grocery shopping. The load is to be fixed to the rack with straps.
I started by measuring the beams of the bike, especially the seat tubes and the seat stay. Seat stays of most bikes have a little beam where the rear brakes are located. This beam with the seat stays forms a triangle, and I thought:
It must be possible to hang the rack on the seat tube and support the weight by resting on the little triangle.
So I went to the drawing board. I downloaded a 3d bike model as a base and worked on it in Blender, adapting the width and angles of the bike parts to resemble my own bike.
Then I developed the general construction. When my concept worked out on the drawing board, I prepared the crucial part for manufacturing. The beams were to be made of wood from the DIY-store.
I decided to have the connecting parts 3d-printed and converted my construction drawing into STL format. After uploading my STL-files, my 3d-printing service located a few crucial parts that could result in manufacturing failures. I corrected them in Blender, exported to STL and tried again. This time, I got encouraging feedback and decided to hit the “go” button!
My objects were delivered one week later and I liked the result. I went to the DIY-store and got the beams in the right width, cut them into the right proportions, went home and put it all together.
The result was breathtaking as you can see in the pictures! The rack was really easy to attach and stayed save in place. I put weights on it and the rack carried them without any problem. I went out for a ride with six 1 Liter bottles (=6kg / 13 lbs) and all went perfectly well. I am safe to say, that my bike rack is good for 5kg as are most racks that are not attached to the cogset.