To Turn Fast or Slow, That is My Question

I'm a newbie. I want to use a small stepper to slowly tilt a 16" globe to simulate the seasons. Another would spin the globe in real time. The final drives would run indefinitely and extremely slowly. I can program the steppers to rotate the desired excruciatingly slow speeds, or, using gears, run the motors at higher rpm. Currently using an Arduino Uno R3 and cheap 28BYJ-48 with 12v, 1000mA, I notice the motor skips steps when the rpm's are low enough for me to notice. When I spin it fast I don't know if it's skipping. My question is: Do individual stepper motors have an optimum rpm where skipping is least likely, or is there a general rule of thumb for all steppers?

Thanks in advance!
-Matt

Steppers have their maximum torque at zero RPM, so that's their optimum :-)

To do just one rotation per day you likely want some gearing. It you move that directly you have just 3200 steps, which likely makes each step quite noticeable on something as large as a globe. How about salvaging from a wall clock?

Regarding lost microsteps, that's a known issue. They're not really lost, the next one is then a double-microstep. Google for "StepStuck".

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