Quote Originally Posted by Jonathan View Post
No... in series it's 6.2A and in parallel 12.4A.
Hmm, surely the parallel connection will draw twice the current of a single winding, not twice that of the series connections. Similarly the series connection will draw half the current of a single winding, not half that of a parallel set-up.

Not at all - how strong you make the gantry with a single screw is largely irrelevant with regards to racking....
To rotate (rack), the rails do not have to deflect much at all...
This happens with almost every build log - starts off thinking one ballscrew will be fine, then by about page 3 we manage to persuade that it's not.
Lol, okay I get it :tup: I'll go for two ball-screws.

I still wonder though; why isn't it better to use the same screw pitch for all axis, so that providing the motors don't run out of torque, each axis will have the same speed and resolution?

I really don't want to go the rotating ball-nut route, nor linking the ball-screws with a belt. Going with dual ball-screw I'd like to use two motors. I'll bear the tedious tuning procedure when I first get it up and running. At least I know to expect that now thanks to you guys!

Think what happens if one motor has a slightly different load.. then stalls.


My question was really about why it is better to power each motor and ball-screw from a separate drive circuit, rather than just using both motors from one circuit. The motors can surely still individually stall, even with two driving circuits.