Large tetrapod disco ball

What?

It's a large 3D printed tetrapod disco "ball". 3D printed, reinforced with threaded rods so it (or parts of it) can't fall on peoples heads.

Why?

Well, the world definitely needs something like this. Also, why not?

Required materials

If you don't want to hang it somewhere, just filament and glue is all you need from this list:

• 4x 1kg spool of fliament, e.g. https://www.amazon.de/dp/B0BNBK48XF/ 
• 1x 2k glue, e.g. https://www.amazon.de/dp/B000KJP0QK/ 
• 1m of threaded rod M6, or 4x https://www.amazon.de/dp/B0BT7XQ78W/ 
• 1x M6 ring nut, e.g. https://www.amazon.de/dp/B0CQV62T9J/ 
• Threadlocker, e.g. https://www.amazon.de/dp/B00Y8DOMCC/ 
• a lot of glue on mirror tiles, e.g. 2x https://www.amazon.de/dp/B09V33PDH4/ 

Printing

You need a reasonably large 3D printer, as the 4 arms are slightly below 210x210x280mm. OR you cut the arms into two pieces.

For a hangable tetrapod you need to print:

• 3x Arm.stl
• 1x Arm_with_hole.stl
• 6x Connector.stl
• 1x Jig.stl (more on that later)

In case you don't want to hang this tetrapod, you can print 4 identical arms.

I printed the parts with 3 perimeters and 10% infill from PLA which worked well. You need about 3,5 spools of filament in total so I recommend getting a cheap one like Overture linked before.

Assembly

1. Cut the threaded rod into 3x 233mm and 1x 300mm pieces
2. Fix the threaded rods in the jig as shown in the picture and weld them together. The PLA jig is fine for short welds. This is the structural support if you want to hang this above peoples heads.
3. Glue everything together, get a second person to help if possible.
   1. Put one arm on a table and insert 3 connectors and the structural support into it with a lot of glue. The longer arm of the support goes into the arm with the continious hole. 
   2. Add glue into the holes in the other arms and add one connector each.
   3. Slide each arm onto a free end of the structural support
   4. Carefully slide all three upper arms into the bottom, first arm.
   5. Secure everything with tape and remove excess glue.
4. Once the glue has dried, spend about a day glueing mirror tiles to the tetrapod. I recommend cutting long strips and glueng them along the circumference of the arms.
5. Screw the the ringnut onto the free end of the threaded rod, secure it with threadlocker.
6. If you really want to play it safe (I recommend doing so!), add a second suspension point so you can use a safety.
7. When using a disco ball motor or any other support to hang it, make sure it can handle more than 5kg of load.