The design for the Scotch and Yoke is based on this depiction of the machine
Here is the DXF file I made for the design
I created the circle and mechanism based on the description, and in order to connect them I made a hole in the circle and an empty area in the mechanism. A pentagonal cylinder will connect the two pieces and move the mechanism. In the bar area of the mechanism, I put a hole in the middle of it to put two brass tacks. This is to ensure that the mechanism stays straight during the rotational motion. I placed this whole mechanism onto a chipboard backing to keep everything stable during the machine’s motion.
Here is a photo of the final prototype:
While this prototype did work, it was not without its flaws. The brass tack in the middle of the circle impeded the motion of the machine and the backing interfered with the pentagonal cylinder’s motion as well. In theory, this mechanism prototype works, but there are some flaws in the backing and anchor points. In addition to this, I did not size the later cut correctly on the chipboard so a part of the mechanism got cut off.
Here is a video demonstrating the motion of the prototype.