I wanted a honeycomb filter for my flash but it was either overpriced, cheaply made, or both. So I designed one around the contours of my Altura AP-N1001 flash in Blender. The shape is fairly universal to flashes of this type.

Please note that I scaled the model in a slicer (I used Simplyfied3D) so that the widest end is set to 74mm to fit my flash. Your size may vary. In S3D, the model imports are very tiny. In Cura, it's a little too big.

I used standard PLA settings, no support if you position the model face-down. I have not experienced any heat issues but you can print with more robust material. I suggest sticking with the black color.