A 3D-printed curved sheet of plastic showed promise as LED diffusion layer, but it was very flexible and I worry about its suitability to be the outermost layer of Glow Flow. The flexibility means people who try to handle Glow Flow by grabbing this outside layer may damage the sheet, and the flexibility also means it might be difficult to control its distance and therefore diffusion.
As an experiment to increase rigidity, the next print added a wave texture to the outer surface, giving it appearance of horizontal ribs. This shape should resist bending more than a texture-free sheet of plastic. It would also diffuse light differently, which may or may not look better. At the very least it is worth exploring and a vase mode print is a quick experiment to find out.
On the front of structural strength, the ribbed version is indeed noticeably more rigid than the featureless sheet. It still doesn’t feel rigid enough to withstand handling, but enough that I think it can maintain a particular distance (and therefore diffusion) without worry. Certainly good enough to be worth further experimentation down the line.
On the topic of visual appearance, the varying angles of these ribs picked up light from both above and below, presenting a blending of lights that correspond to the ribs themselves. On the downside, the print layer direction seems to magnify a problem where the light is focused into a vertical line that is extremely visible from certain angles. The featureless sheet also had this problem but not as serious.
The ribbed sheet is more interesting than a featureless sheet, and this opens the door to additional experiments on how we might use physical strengthening geometry to aid diffusion. The next experiment: introduce bending along more than one axis for a diamond-like pattern.