Yes, I've learned this the hard way. And I got really disapointed about the cheap design and motors
Basically I was increasing the driving voltage and changing the stepping time on the microcontroller to see how fast I could step the motor before it starts skipping.
6V - 200 steps/s
12V - 250 steps/s
18V - 330 steps/s
(all values are approximate).
So I gained a little bit of speed but at the cost of much higher power consumption (also the motors were running warm). In the end I decided that it was not worth the trouble and that I would need new motors for faster slewing
The main lesson I learned is that these motors are cheap low torque 7.5 degrees per step motors. There is a gearbox (with gearing of about 100 times) which increases the torque and reduces the step size to give the mount small enough movement step for acceptable tracking. The gearing limits the maximum speed at which the mount can be moved so fast slewing is out of question.
On the other hand the more expensive GOTO motors utilise smaller step size motors (usually 1.8 deg/step) and use microstepping instead of very high gearing (they may use gearing as well but not with such high ratios). Hence it is possible to move the mount at a much higher rate once the microstepping is off.
Oh well, at least it was fun playing with the motors and now I know where I stand, or better said how slow the mount can move.
Again, thanks for everyone's help
