Perfect supports with single extruder

This is a new way of getting perfect supports and interface layers without using soluble supports or any tricks that need dual extruders. More info in the thread on forums: The only hardware I’ve added is a fine tipped permanent marker, actuated by a kind of solenoid (rotating diametrical magnet inside a coil with a bias-magnet to prevent sticking, pushing on an external magnet). The things you need to replicate this is a few bearings, some magnets, a marker, some enameled copper wire, and a spare output (I used an output on my raspberry pi, hence the slight miss in synchronizing with print).