I couldn't find any suitable, customizable holders for RGBW LED strips, so I made a very simple clamp to estimate the placement of the strip in my ceiling space without gluing it or buying ready-made profiles. This clamp is made in SCAD format and has several basic variables for configuration. The print was made with Bambulab PETG-HF Gray on P1S, you may need a bit different clearance for PLA.

The idea is to be able to fix the strip in any ceiling space without gluing it to estimate the location of the wiring.

There are several modules that can help you with that:

• The straight module directs the strip to the wall of the ceiling space and diffuses the light from the strip instead of a separate screen.
• The curved module at the corners is necessary to close the circuit without interruption. Only outer bend at the moment so you can cover only convex shapes.
• The twisted module is needed to prevent breakage, depending on the elasticity of strip. You will need one non-mirrored module before and a mirrored one after the curve.

It is also worth noting that straight and twist pins need lower tolerance than curved pins.

Connecting the modules is pretty trivial. Just follow the angles:

Here is some params to use in order to get these modules: