This design uses internal bevel gears to fix the rotation of the trays. This is my first attempt at a mechanical design, and feedback is encouraged
Required Parts:
x5 5mm OD 5mm depth M3 heat-set-inserts
x5 M3x8 screws
Your favorite 3d print adhesive (I happened to have tacky glue on hand)
Small Furniture Pads (or something to keep the tray from sliding
Small Weights (I used some washers)
Print:
(whatever show material you like)
x1 Bottom Tray
x1 Middle Tray
x1 Top Tray
(these parts do not show externally, so print them in whatever material)
x3 Small Gear
x2 Base Gear
x2 Nugget
x1 Gear Mount
Assembly:
Clearances are not amazing, so some post processing is near guaranteed. Sand down parts as needed. Add the 5 heat-set-inserts to the Gear Mount part. Wedge the Nuggets inside the hole in the Base Gears. Put the 2 Base Gears above and below the Gear Mount and add screws going through the nuggets. Add the Small Gears to the side axles of the Gear Mount. Insert the whole mechanism into Middle Tray at the correct orientation, and add the final 3 screws where needed. Glue the top and bottom trays to the mechanism. Add weights and furniture pads to the Bottom Tray with whatever means you like.
The author marked this model as their own original creation.