…that we experimented with and what we found.
57 oz-in 12V 1.3A NEMA 17
Pros: availability (free 2-day shipping arrived in time for club experimentation)
Cons: Exceeds current capacity of Adafruit motor shield (v 1.2)
Observation: Heat buildup on motor shield cannot be ignored for even short run times. Shield needs to be modified by piggy-back chip or heat sink or both.
Adafruit 12V 200x stepper Product #324
Pros: It has proven compatibility with Adafruit motor shield (v 1.2).
Cons: The 3mm mounting screws are difficult to find.
Observation: Works well. However, we would like a less expensive alternative for smaller individual polargraphs. Also, the motor builds up considerable heat when driven by 12V for more than an hour or so.
28BYJ-48 (5V geared mini-stepper with driver board)
Pros: It is prolific and 1/4 the price per motor when purchased in sets. Can be driven by Arduino without a motor shield.
Cons: It is relatively slow. Will take some coding to integrate with PolargraphController software.
Observation: The low-cost goal demands that we explore further: