I copied the classic kids toy to make some of my own marble run pieces. It's a simple design which goes together with a little glue, it's scaled for 10mm ball bearings. I added round disks to the top and bottom of the pieces, this allows them to be rotated to any angle to create more interesting structures. The whole pattern was set up to be one long thin strip, this means it can fit into the skinny scraps that are left over from most projects. (svg here)
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