Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: Richiemag on February 02, 2015, 09:25:06 PM

Title: slaving
Post by: Richiemag on February 02, 2015, 09:25:06 PM

 
Hi Everyone
I am very new to the cnc / Mach3 world about a month.
I am building a cnc router that has two stepper motors on the same axis.
I have read the instructions from Mach3 and in this case slaved my y axis to the A axis, no problem.
Both motors turn in the same direction but they are not in sync with each other.
I have 2 home switches on each side of the gantry, according to the instructions when I zero the Y one side of the gantry with hit the home
switch, stop and back off and the Y does just that but the A hits its home switch and keeps traveling.
I have tested the home switches by the LED's on the diagnostics screen to confirm they work.
Can anyone please help ??
Thanks Richie.
__._,_.___
 8)

Title: Re: slaving
Post by: ger21 on February 03, 2015, 05:18:36 PM

What do you mean by "not in sync"? Do they move at different speeds?
Can you post your .xml file here?

Title: Re: slaving
Post by: Richiemag on February 03, 2015, 07:54:05 PM

Thanks Gerry
What I mean is that my gantry is racking because the motors are slightly different speeds .
So the gantry racks by as much as 1/2 " per every 4"n of travel.
Motor setting are exactly the same and the second motor (A)  is slaved to the ( Y ) in this case .

Title: Re: slaving
Post by: ger21 on February 03, 2015, 10:32:56 PM

Is this all the time, or only when homing?
If only when homing, make sure the homing speeds are  the same in Config >Homing and Limits.

If it does this all the time, I don't have an answer for that, as I've never seen that happen.

Title: Re: slaving
Post by: Richiemag on February 04, 2015, 07:30:16 AM

OK thanks Gerry but it happens any time I jog that axis.

Title: Re: slaving
Post by: ger21 on February 04, 2015, 08:00:42 AM

Are you sure the speeds are the same. Both velocity and acceleration in motor tuning?
If they are, I'd uninstall and then reinstall Mach3.

Title: Re: slaving
Post by: Overloaded on February 04, 2015, 08:20:45 AM

Might also verify that both are mechanically identical.
Exact same pulleys, screw pitch, rack/pinion or whatever applies.
Russ

Title: Re: slaving
Post by: Richiemag on February 04, 2015, 09:23:47 PM

Thanks Guy's I will keep trying .