Modular Marble Run Kit

A simple modular marble run kit for 16mm glass marbles, with potential for further parts to be added.

Specifications as follows: Each piece has a height of 30mm, with 18mm diameter channels. The straight pieces are 26mm wide but this can vary from piece to piece. The outside diameter of the inlet and outlets is also 26mm and it's preferable to maintain this where appropriate. The top of each section has a prominence that encircle the marble channel with a height of 1.3mm and diameter 21.2mm. This fits into a socket in the bottom of each piece which measures 21.6mm diameter and 1.5mm deep. The props have a top prominence measuring 9.6mm diameter and 4.5mm high, which fits into a socket 10mm diameter and 4.5mm deep (with a domed roof for tolerance and printing ability).

All created in Tinkercad.

Suggestions, or compatible designs very welcome - thank you!

https://youtu.be/Ho8QCIx14d8

You'll notice in the video the top piece is a little loose where it fits onto the swirl bo