I wanted to test out how well different wall geometries block out light, so I printed a 100x100 mm square that was built up out of 4 different thicknesses. Then I painted the flat side with two different types of white paint and finally used a light box to view how well the bare plastic and painted plastic block the light. The results are interesting and highlight that I need to switch to a different plastic, this one is much to translucent. Even the thickest walls and the best paint combined failed to block out all visible light.


I tested out some generic white spray paint and some rubberized spray on roof sealant. The roof spray is super thick and very flexible, however it does a poor job of blocking the light and does not stick well to the plastic. I can scrape it back up easily with my nail. It may stick better to a primer, maybe a coat of black would help with blocking the light as well.Anyway I'm picking up some black PLA plastic, and will repeat the experiment with that. Hopefully that blocks the light completely. If not I will try some black primer as well. I also want to try scuffing the paint to see how well it sticks, and placing it over a heat lamp and measuring how well each wall and paint combo blocks heat.