I was having some burn on my plants due to the intensity of the LED grow lights so I made this diffuser to snap over them. I made them in three different thicknesses. You can extend the scale in one direction to make them long enough to fit your 3D printer.

I printed them with the circle on the platform.

Grow Light: Feit Electric GLP24FS/19W/LED Dual Full LED Plant Grow Tube Light, 1.73” H x 23.33” L x 4.9” D, 450 Nm Blue, 655 Nm Red Spectrum