Mr Bean,
From experience watching my customers come up with various ideas to drive their axes, there have been mixed opinions regarding belt drives. I have one customer in particular that is using a 25mm (1") wide belt driving an axis 3.5m (137.8") long and there was a noticable bounce in the belt as the machine axis started and stopped. It took a little longer to tune in the PID control of the servo drive but in the end it ran quite smooth. We have other customer that runs over a shorter distance without any problems at all. I personally think that the guy with the 3.5m travel should have used a much wider belt and used support idlers on the belt return side to eliminate some of the bounce. I guess what I'm saying is that belt drives can be good if they are engineered properly for CNC use in your particular application. Nice and cheap, I agree, and easy to install. Let us all know what you decide to do when the time comes I will be interested to hear the outcome.
"A Helicopter Hovers Above The Ground, Kind Of Like A Brick Doesn't"
Greetings From Down Under
Dave Drain
Akela Australia Pty. Ltd.
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)