I was tired of lugging around my 6kg Tronsmart Bang Max speaker, so I designed a bracket to secure it to my bike rack. Originally made for the Racktime Snapit 2.0 system, this design can be easily modified to fit your own rack fixing system. Keep in mind that while you can still use your speaker while riding your bike, the sound will be directed behind or in front of you, depending on the chosen speaker orientation.

What you will need:

In addition to this print and the rack adapter bracket, you will need to purchase or print two TPU straps to secure the speaker with a recommended length of 70cm or more and a width under 2cm. I am personally using 80cm straps after 65cm ones proved too short. 

You can secure the straps with paper clips or double clip clamps as shown here:

You can also use elastic finger pads to join the strip for a nice and clean finish.

Printing

For a robust print, I recommend these settings:

• Wall loops: 8
• Sparse infill: ≥30%
• Top shell thickness: 2mm
• Bottom shell thickness: 1mm
• Layer height: 0.08mm or 0.12mm
• Support: disabled (supports are really hard to remove on this model)

Scale the model by approximately 1% ± 0.5% based on your filament material to account for shrinking and ensure the bracket fits the speaker properly. I successfully used 1% scaling for PETG and 1.5% for ABS.

Assembly

1. Mount the rack bracket adapter on the printed piece by using provided screws. 
2. Check that the mount is rackable and determine speaker orientation.
3. Fit the speaker onto the base. Evenly push on both sides, the rubber of the speaker will fit at some point.
4. Add both TPU straps and attach the speaker firmly. 
5. Secure the staps using paper clips, double clip clamps and/or elastic finger pads. 

Adapting the design to your needs

For those familiar with Python, the model is fully parametric and the CadQuery script is available. This script will generate a step file in the current directory, that you can directly import into your favorite slicer or further convert to a mesh file. Consider using CQ-editor to edit and render the parametric design using a GUI.