"A 3D Printed Dancing Christmas Tree" is a model I designed for my wife, who performed quite an interesting dance in front of me in an attempt to illustrate the animation she desired for a dancing Christmas tree. And no, I did not video her dance, but it was quite humorous!

The tree features 8 alternating pivoting layers, layer 1 being the lowest layer of the tree, and layer 8 being the star at the top of the tree.

As usual, I probably forgot a file or two or who knows what else, so if you have any questions, please do not hesitate to ask as I do make plenty of mistakes.

Designed using Autodesk Fusion 360, sliced using Ultimaker Cura 4.12.1, and 3D printed in PLA on Ultimaker S5s.

Supplies

Soldering Iron and Solder.

Thick cyanoacrylate glue.

Double sided tape.

Step 1: Parts.

I acquired the following parts:

One N20 6VDC 50RPM gear motor.
One dual AAA switched battery pack.
Two AAA batteries.

I 3D printed the following parts at .15mm layer height, 20% infill unless noted otherwise:

One "Base.stl".
Three "Bolt (M8 by 1.25 by 6).stl".
One "Cam.stl".
One "Case.stl".
One "Coupler.stl".
One "Cover, Base.stl".
One "Cover.stl".
Seven "Gear (1.56m 9t).stl".
One "Gear, Thick (1.56m 9t).stl".
One "Layer 1.stl".
One "Layer 2.stl".
One "Layer 3.stl".
One "Layer 4.stl".
One "Layer 5.stl".
One "Layer 6.stl".
One "Layer 7.stl".
One "Layer 8.stl".
Thirty five "Ornament.stl".
One "Yoke.stl".

This is a moderate precision 3D print and assembly model using at times very small precision 3D printed parts in very tight spaces. Prior to assembly, test fit and trim, file, sand, etc. all parts as necessary for smooth movement of moving surfaces, and tight fit for non moving surfaces. Depending on you printer, your printer settings and the colors you chose, more or less trimming, filing and/or sanding may be required. Carefully file all edges that contacted the build plate to make absolutely certain that all build plate "ooze" is removed and that all edges are smooth. I used small jewelers files and plenty of patience to perform this step.

The model also uses threaded assembly thus an M8 by 1.25 tap and die will assist with thread cleaning if necessary.

Step 2: Assemble the Tree.

To assemble the tree, I performed the following steps:

Glued the thirty five "Ornament.stl" into the "Layer 1.stl" through "Layer 7.stl" (layer 1 is the longest, layer 7 is the shortest, and layer 8 is the star).
Inserted the layer 1 assembly into "Case.stl" making certain the layer was level, then secured in place by pressing one "Gear (1.56m 9t).stl" onto the hexagonal shaft, making certain one gear tooth pointed straight up and one gear gap pointed straight down.
Repeated the previous step with layers 3, 5 and 7.
Inserted the layer 2 assembly into the case assembly making certain the layer and adjacent layers were level, then secured the layer in place by pressing one "Gear (1.56m 9t).stl" onto the hexagonal shaft, making certain one gear tooth pointed straight up and one gear gap pointed straight down.
Repeated the previous step with layers 6 and 8.
Slid "Yoke.stl" into the case assembly making certain it slid side to side with ease.
Inserted the layer 4 assembly into the case assembly making certain the layer and adjacent layers were level, then secured the layer in place by pressing one "Gear, Thick (1.56m 9t).stl" onto the hexagonal shaft, making certain one gear tooth pointed straight up and one gear gap pointed straight down.

Step 3: Final Assembly.

For final assembly, I performed the following steps:

Pressed "Cam.stl" onto the gear motor.
Pressed the motor assembly into the case assembly.
Glued "Coupler.stl" to "Base.stl".
Glued the base assembly to the case assembly.
Turned the battery pack switch off, inserted the two AAA batteries into the battery pack, then secured the battery pack to "Cover, Base.stl" using double sided tape, making certain the battery back switch was accessible through the slot in the base cover.
Threaded the battery pack wires through the base and coupler then into the case assembly then pressed the base cover onto the base.
Soldered the battery pack wires to the motor.
Positioned "Cover.stl" onto the assembly, then secured in place with three "Bolt (M8 by 1.25 by 6).stl".

With assembly complete, I turned on the switch and the tree commenced to dance!

And that is how I 3D printed and assembled "A 3D Printed Dancing Christmas Tree".

I hope you enjoyed it!