August 17, 2023
Description
The design is simple using only 3 basic parts: a 20 sided icosahedron Frame, 19 Spikes, and 1 Base (to mount it on a tree).
The Star is approximately 17.6 cm in diameter. The parts of this design can be scaled to any size, using your slicer's scaling options.
I used Polymaker Polysmooth Transparent PLA filament. It can be sprayed with Isopropyl Alcohol (IPA) to smooth its surface. Be sure to do it on aluminum foil (or a metal) surface, because after it dries the IPA that dripped off leaves a residue of PLA which can be hard to get off.
After spraying, not touch it until after the IPA dries, otherwise you will leave fingerprints. I would recommend only spraying the final assembly, not the indivudual parts.
I used this Acrylic Cement (https://www.tapplastics.com/product/repair_products/plastic_adhesives/tap_acrylic_cement/130) and this Small BD-25/2 Hypo Applicator (https://www.tapplastics.com/product/repair_products/plastic_adhesives/hypo_type_solvent_cement_applicator/409) to glue everything together. This cement works great with PLA. Note that it works in seconds, and should only be used in a well ventilated space.
For the lights I used these Govee fairy lights.
https://www.amazon.com/Govee-Operated-Waterproof-Silver-Plated-Festivals/dp/B07R8V53S4
It took about three 1 meter strands (20 LEDs/strand).
To assemble it, I picked one side of the Frame and ran lights into the center, then using tweezers I pulled about 3 LEDs out each hole in the Frame. Bending the wires so there was one LED at the tip, one in the center, and another towards the base of the spike. Pressing the Spike against the Frame I ran a bead of Acrylic Cement around the three sides of the spike and held it for about 20 seconds. Superglue would probably work too. After repeating this 19 more times, I glued the Base to the last open position on the Frame.
The lights are powered by 2 3V CR2032 batteries in series. The batteries provided 6V, so to power the star I cut off the battery packs, then used a cut off USB cable where I connected the USB cable 5V power wires to the 3 light strings in parallel.Then using a small USB power supply, I attached the star to the end of a string of lights on the tree.
Even with the lower USB voltage (5V) the star was still really bright. In fact, so bright that I added a 100 Ohm resistor in series to the +5V wire to reduce the brightness.
I included 2 Print Profiles: One for a 256x256 bed, and a second one for an Mini 160x160 bed.
Printer:
Prusa MK3S
Rafts:
No
Supports:
Yes
Resolution:
0.15
Infill:
No
Filament: Polymaker Polysmooth PLA Transparent
Notes:
Using the Prusa Slicer, I printed the Frame and Base with the 'Supports on Build Plate only' option. And for the Spikes I enabled a 2mm skirt.
License:
BY-NC
mcmaven
