I don't think driving two steppers will make it run any faster. Screw drives have backlash problems (play in the screw mechanisms) unless you go to adjustable nuts and funny screw threads (ACME etc) then you have servicing problems. Stepper speed is a frequency limiting factor governed by current in the coils (and microstepping won't make it quicker - you're still up against change in time to drop held current). Dual Z- motors seem to be about keeping the gantry balanced (stop it cockling over and locking in place) and the reduced current in the coils means you can actually turn them quicker. You can also increase speed by upping the voltage.
I can run mine at about 400RPM on the X/Y axis and because I'm running half the current through each of the Z-axis motors, they can run roughly twice the speed
[www.daycounter.com]
I use this site to calculate the max speeds and it's worked for my stuff so far (running Nema14's at 250mm/s, slightly under their max speed)
I can run mine at about 400RPM on the X/Y axis and because I'm running half the current through each of the Z-axis motors, they can run roughly twice the speed
[www.daycounter.com]
I use this site to calculate the max speeds and it's worked for my stuff so far (running Nema14's at 250mm/s, slightly under their max speed)