Print-in-place piston and rod fidget keychain

What's this?

This model represents a piston and its connecting rod. While not a faithful copy of the components in an actual engine (more realistic geometries may be coming soon), the piston head features two slots where o-rings would be in a real car and a faux wrist pin embossed in the surface.

The real magic happens on the inside: the print-in-place hinge allows the rod to rotate independently of the piston, giving this print an excellent fidgeting potential - although the most fun part is actually “breaking” the hinge off the build plate.

A keyring can also be attached to the big end of the rod, so you can customize your keys or your backpack and tell the whole world you're a true petrolhead.

Dimensions: Ø 24mm, h 43mm, about 5g of PLA

How to print?

This is a fully print-in-place and supportless model - in fact, it's important that NO SUPPORT is used, otherwise the hinge will not work.

• The piston face should be on the print bed;
• 0.2mm layer height should work just fine and guarantee a nice final result in around half an hour;
• I suggest incresing the wall count to make sure the rod and its hole don't break;
• Once printed, remove the model from the bed and simply fold the rod with a little force: it should snap out easily. After a few cycles of folding back and forth it will become looser and softer.