Marbulous Double Spiral

Marbulous, Marble Genius, Marble Run, Toto Toys Standard
Post 35mm h x 27.5mm dia, Boss 6mm h x 23.5mm dia
Posts 100mm between center, 17.5mm I.D. tube, 4deg slope

This model has 2 posts and measures 1 post high.

I set the support overhang angle at 60deg to provide support for only the post undersides.
I set the support for only touching buildplate.

The extra high rim around the input side is there because marbles can enter the piece at high speeds, and to mitigate this extra velocity, the rim helps keep the marble in/on the track.