Note the asterisk. While this does technically move the pen up and down, it is far from perfect. Very far from perfect. This piece was designed to move the pen up and down 5cm in 180 equal steps meaning that it would move precisely 2.77mm each step. What this video shows is a pen moving 5cm, but only a usable 3.5cm in 180 randomly spaced steps.
So what have I learned? When you spend 5 hours printing, and then another 6 hours sanding and filing, and finally resorting to acetone and WD-40, clearly the pieces should have been better designed. The servo motor I am using for this piece is not at all strong enough, but I have two weak servos and one strong one (which is reserved from moving the stepper motor).
The pieces have far to much ‘wiggle room’, and this resorts in a lot of the inconsistencies. Out of the 4 prints that make up this piece, 3 will have to be redesigned and printed again. Fortunately they will just be minor changes, but as they are designed right now, they will not lead to a successful tattoo. The biggest problem is the pen only being able to move 3.5cm. A lot of this has to do with the length of the pen, and how the motor sits lower than the stabilizing rod.