As I was able to access Texas InventionWorks during the semester, I chose to construct my mechanism using 3D printing. I chose this over the alternative offered, laser printing, as I felt that the better 3D design abilities would lend well to the pins and joints necessary without requiring additional hardware.
(insert pin and hole set image)
I began with a test print to find the best sizes for pins and holes to allow for smooth rotation and sliding in the pins and slots. As I was planning on making the entire assembly approximately 6in square, the pin sized that seemed best when I drew out the mechanism was approximately 1/4in. As I knew I wanted a free moving joint, I wanted the pins to have some clearance (be smaller) within the holes. To test the exact sizes, I printed out a set of holes at 0.25, 0.26, and 0.27 in and a set of pins at 0.25, 0.24, and 0.23. I found that no clearance (0.25-0.25) would not fit together, while 5 thou of clearance (radius) produced a rubbing fit. I found that 10 thou of clearance produced a free fit, with great joint mobility. Because of this, I chose to use 0.25 pin and 0.27 hole, as this allowed for the largest pins in my testing range and I was slightly worried about pins being too fragile. This extended to the slider block, in which I used the same 10 thou of clearance (on both sides, 0.75-0.77) to produce a sliding fit.