External toothed compound gear set
This gear set allows you to demonstrate three external toothed gears that are meshed together. A pin be removed that allows you to move the big gear to make a compound gear set. The gears were used from the Thingiverse Gear Trio version 3 file. The gears were enlarged 250%. Here is a link of the video.
https://www.youtube.com/watch?v=cNX_qSCJD5U
https://www.youtube.com/watch?v=qip0_5czymk