by elfnor, published
Turn the crank handle and the marbles are pumped up the vertical shaft to return down the spiral.
Based on the mechanism seen here: http://www.sentex.net/~mwandel/marbles/pump.html.
This marble pump could be combined with many of the other marble runs found on thingiverse.
I made the front, back and top panels in acrylic so that one can see the internal cylinder and piston mechanism. I've provided both stl and dxf versions of the panels for either printing or laser cutting. I actually cut and drilled mine by hand
As well as the printed plastic and cut acrylic you'll need:
8 small panel screws. (4g x 10 mm)
2 metal rods 3 mm diameter, 110 mm long.
12 glass marbles ~15 mm diameter
~1.5 m of 3 mm filament for the rails and supports.
The spiral rails, vertical supports and right angled bends were made by bending up 3 mm HIPLA (http://www.diamondage.geekofarm.com/?page_id=150). If using ordinary PLA it will probably be necessary to gently heat the filament to get nice curves and avoid breaking it.
1 set of crank_pieces
Print or Cut
Have a look at the marble_pump.blend file, the photo and the render to work out assembly. Depending on the printing quality you may need to sand the piston and cylinder to get a good fit.
The crank could be connected up to a motor for amusement.