Uno+shield with 4 drivers.
I know to prefer series over parallel and why.
The cnc shield can clone an axis to a 4th driver or control a fourth motor by setting up pins 12 and 13 for signal.
I’m going to run this project on grbl, which as far as I can tell will not run 4 axes simultaneously from the uno (i know about the mega project, but I’m not there yet).
What I don’t know is what “simultaneously” means. Well, in this context. I can set it up but can’t use it?
Is it determined by the program? Run xyz or xza for instance? Would I still have to unplug one of the axes?
I think it would be neat to have a rotary set up and not screw around with plugging / unplugging, in which case I’d go series on xy.
If it wouldn’t work that way (I think it might not), just pick the axis that might have to move the fastest (like on a parallel finishing pass maybe?) and clone that driver to a? Or does it not matter at that point?
You can always change it later. It would either just wire the double axes in series, or mirror one axis. If you mirror it, grbl doesn’t know the difference. If your ever bored, you can take it apart again.
What, me get bored? lol.
I’m going series on both sides. I’ll mess around later and see how A behaves with all three other drivers set up.
Thanks guys.
I think I would clone A to the Y and wire both Z’s up in series because the Y can use all the power it can muster and the Z is assisted by gravity (and doesn’t move as much).
The simultaneous use of only 3 axis’ on the Uno is one of memory and flash constraint apparently - It’s never going to happen on an Uno. You will need to upgrade to a Mega at least for the 4th axis.
Only one z. Wiring direct does give more torque then?
My question about the A was more “would it let me avoid plugging /unplugging”. You know, could I leave a stepper hooked into it, and would it turn for a program that was only xza? Probably not, I know, but I don’t know.
No. Not until the drivers are using all the source voltage to reach the desired current, which happens at high speeds. At milling speeds, you get full torque with serial wiring or separate drivers. The main motivation for dual drivers is dual endstops, although the simpler wiring and dropping costs of 5x boards is making it appealing for non endstop users (like myself).