Designing Things That Move in Sketchup for 3D Printing
A captive joint is a moveable connection that comes out of your 3D printer already assembled and working.
Captive joints tend to be mechanically simple hinges, ball joints, and chain links. Their simplicity is their power. A 3D printer can quickly build objects with hundreds of captive joints that would take days to construct by hand. Poseable action figures, clothing, and the chainmail shown are examples of simple captive joints assembled into complex structures.
Pins are small, round snap fittings that are pressed into place to make a connection.
They can be a versatile replacement for hardware. Here, a single pin acts as a point of rotation, and two or more will hold parts firmly together.
Pins are like bolts, except you get to make them in exactly the size and shape you need.
Gears are great for creating complex motions or transferring movement through a mechanism.
Gears are in every mechanical device you can imagine. They have existed in some form or other since before recorded history, and are the basis for an incalculable number of clever devices that make everyday life possible.