I think that the timing is based on the hall sensor and the stationary magnet.
A motor that can spin at a bit over 1000 RPM gives 18 frames per second.
You might be able to get away with less if you are doing less animation and simply displaying text.
4' home made object spinning 1000rpm is not something I want to be near! 
Edit: Before you tackle your large scale POV project, make a small one.