I saw wiky1982's design and rather liked it, but it didn't fit the current standard mini lights we have in the US which have a safety latch on the size. So I redesigned it from scratch with a couple changes.
Changes from the original:
- Slips over just the "bulb" portion of a mini light
- Should fit lights between 4.4mm to 4.8mm
- For 5mm LEDs, try printing scaled up 1-2%
- Made the fins a uniform thickness (1mm) to make them easier to print
- Decreased overhand angle of the lower slope for easy of printing
- Enclosed the end so they are more "bulb" like
Fusion 360 source file included.
Update 2018-12-10: I've split the core off it to its own remix if you'd like to design your own using my style of bulb holder.
Many Transparent PLA or PETG
Print time for 6 on a Prusa i3 Mk is about 1 hour at 0.3mm layers.
For PETG, I would recommend truing off part cooling. The thin walls at the bottom often had bad layer adhesion when part cooling was enabled. Allow bed and printed parts to cool before attempting to remove.
Due to many LED colors being a UV LED plus a phosphor, florescent filaments can have interesting color changes when lit internally.