I have already tested the threaded rod (as seen in my previous post) but with such a large project I thought it would be a good idea to test out some of the other pieces as well, even before I get really started. I have fairly small arms, so the piece I tested probably won’t fit other people.
My current design is 8 cm tall and 57 cm long, but I will need to change it to be about 11 cm tall and anywhere between 60 and 76 cm long. (I tend to work in inches and feet, but because my 3d printer works in millimeters, I have switched over to doing this entire project in mm’s and cm’s). I don’t want to make it any taller than 11 cm in order to ensure the pen can still reach the thinner portions of the arm.
The gap in the upper arm piece is to allow for a rod to run along it like a track. This means that I don’t actually need the top piece as gravity will force it to stay flowing along the bottom, but I will keep it there just to make sure it doesn’t get out of line when I move it. I currently have them too thin, so they are very flexible, but I will be able to change that for the next print.