Watt's Parallel Motion #1

This is a representation of one of two mechanisms James Watt invented around 1784. (There's a more complex version I'll upload in a few weeks when I've worked the bugs out). This mechanism runs backwards; i.e. it can be made to do its thing with a motor and crank disk as I show here or the beam may be moved by hand to illustrate the straight line 'output' on the right hand side. In Watt's world the steel rod would have been attached to a piston in a cylinder and driven by steam pressure. The piston would move the mechanism and drive a flywheel around. Flywheel would provide the impetus to keep the whole thing going. What Watt did is find a way to make the piston rod travel in a straight line and still impart motion to a rocking linkage. Here's a link to the thing in action: https://www.flickr.com/photos/steamboat_ed/51765879537/in/album-72177720295454568/

--In addition to the printed parts you will need:
-Three pieces of '8020' (but actually 2020) measuring:
-1: 25 cm long