These 9 3D printing parts will allow you to build your own Marble Machine for Lego Duplo. Once printed in 3D and built, this machine will be a great way to entertain your children. They will be able to create their own combinations themselves. The set was printed in "Robotic Grey" PLA from FormFutura. You can find promotions to buy PLA filament here. You can download all STLs for free here.
If you are a fan of Costantino's work, you can go to his Cults profile to download more of his creations.