I built my CNC Router about 2 to three years ago and I just keep upgrading...or trying. I have NEMA 34 motors moving my X and 2 moving the Y axis, driven by Gecko 203v and a PDMX breakout board. Power supply is unregulated 48v 12.5A. This is a rack and pinion system with dual-vee wheels.
I used to be happy with rapids of 350ipm and machining wood at around 250 ipm. I used to have planetary gears(5:1) on my Y axis, which really limited me to 350ipm. I just removed them last night and in order for the the gecko drives to get or give the motors "full power", I have to set my rapids at 2200ipm!!! While that would be awesome on a daily basis...not very practical.
I thinks a Gecko manual said to use a smaller power supply?
Use different ratio of planetary gear? (Expensive!)