June 11, 2026
Description
This is a 1:6 scale foldable and functional Brompton bike. The bike has a fully functional drivetrain system, meaning you can roll the pedals, and power will be transmitted to the rear wheel through a rubber band 'chain'. The folding mechanism also works the same way as a real Brompton.
Printing:
The model has a lot of intricate folding joints. I had to use PLA+ with a 0.2mm nozzle to achieve the level of detail and z-axis strength I needed. I have tested it with the 0.4mm nozzle and found that the folding joints didn't work. Increasing the scale could probably help. One of the plates in my print profile requires AMS for a more accurate color match. But it's also fine to print without it. Because of the orientation of some parts, it's recommended to use a cool plate. I have failed multiple times with the textured PEI plate. Please also be patient when removing the tree support.
Assembly:
The assembly is straightforward. I tried to minimize the application of the glue. Most of the assembly steps can be done just by pushing the parts together till you hear the click. The chain and brake cables are not printed, but you can easily find the items below on Amazon.
Folding:
Brompton is famous for its elegantly designed folding mechanism, but it can be a little tricky if you haven't done it with a real Brompton. You can find a video here for the proper way to fold and unfold it.
Hope you enjoy building this model, and let me know your comments. It's my first 3d print model project. I'm sure there's a lot to improve.
License:
Standard Digital File License
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