Holy grail marble divider

You probably wonder what in the world this is… I was in doubt to upload this, but perhaps other people like to print this.. i dunno. For me this is a beautiful example of a brillant and elegant solution so a seeminlgy easy problem…

Basically, this thing divides marbles from one to two tracks:

You might think, whats so special about that? And why does the tracks have such a complicated shape? A more simple design could do the same thing:

At first sight this is correct, but the problem arrives when one of the paths is not an exact multiple of the ball diameter… In which case the entire mechanism gets blocked:

Thats why the tracks in the yellow have those weird shapes, they make sure that changing the path does not change the functioning of the mechanism, no matter what you are trying to do. The way this works is that some “springiness” is created. Changing the path length at the bottom has no effect on the spot where the split happens:

If non of this still makes sense (which i get, it took me a while to appreciate how genius this design is), watch the video from Wintergatan of which this is based on. By the way the balls in my design have a diameter of 15mm. If you want to work with a different diameter you will have to scale down the design…