Simple Piston

The fastest and simplest way to make a piston. Origins should be set to their pivot point. To-be cylinder should be the active object. Orientation and/or applied transforms do not really matter. Cardan joints work with quick rig pistons as well. See re-do panel to change track constraint type.

It works really well with bevel shader materials. Note that it only supports two objects!

To properly use cardan joints, the origins of the cylinder and rod objects have to be moved before it can be joined.