This OpenSCAD code is a parameterized sprocket and chain generator. Given a chain pitch, a number of teeth and optionally other parameters, a sprocket centered on the origin is generated. Given an array of sprockets data and sprocket locations on the XY plane, a chain can be automatically generated that wraps around the sprockets - with sprockets rotating either counter clock wise or clock wise - meshing with the teeth of the sprockets. The sprockets and chain and easily be animated to show how the chain moves.

A simple "Customizer" interface is provided to allow experimentation with up to four sprockets.

Note that the chain it perfectly tight as it wraps around the gears and does not support any slack. Therefore, as the chain wraps back around to the first link it will either overlap or gap this link. To control this, the length of the chain in links is echoed to the console window and should have a small fractional value. For example, 72.0037 is the value resulting from the default customizer values which results in a near perfect fit. A value of 72.7 would result in a noticable gap. Adjust the locations of the sprockets to control this value.