Hello all,

I have 2 motors on my Y Axis.  When I manually jog the axis the motors work properly.  However when I try to home the machine it appears that only one of the stepper motors is turning.

I am using POKEYS57CNC and Mach4.

Does anyone know what would cause this issue?

Thanks.

first look in homing signal can be one of y home already activate
second i tell you at begin i also did the gantry motors as master/slave
but there some times message like salve not alignment also some issue with homing
so what i do now as all chines cnc do,connect both servo on same axiss just convert direction on one of them
and all slave problems go away

Thanks KatzYaakov for your reply.

I don't see a home or limit signal for the slave motor in the Machine Diagnostic Tab so I don't think it is active.

I will take your advice of wiring the motors to the same driver if I can't fix the issue.  It just seems it should be not this complicated to assign 2 motors on 1 axis with separate drivers. (I've used another controller flawlessly however it had integrated stepper drivers)

In my last post I said "it appears" the slave motor is not turning during homing.  I have confirmed it is definitely not turning.

Can I ask you how you setup a slave motor to make it home properly (without wiring them to the same driver)?  I would like to try this method.

Best regards.

in pokeys ,you need make bridge on both motors home input ,and conect to yours home sensor

Thanks.  I joined the 2 drivers off the same signal on the controller.  All works well.

Thanks for the advice.

I have exactly the same issue with homing the slave motor. I was expecting to find a software-based solution, as I do in Mach4 when I set up Motor A as slave of another motor. If there is anyone who may know how to configure this, it would be very helpful. Thank you.

Hi Sergio007.

It's been a while and I  need to refresh my memory. However my machine is running the y axis with 2 motors and one is slaved. So I solved my original issue in this post. When I get back to my machine I'll take some screenshots of my config. Maybe that can help you. I *think* I solved it by mapping both motors to the same home switch signal. Be careful with that advice until I check my config.

Hi,
Thank you! That would be great. I found some instructions, which will be able to check tomorrow. Anyway, here is the text  in case the webpage is not available in the future.

#######
Enable Slave Axis in Mach4
There are 2 configuration options:

Option A. Homing with Home/Limit switch on the Master:

First: In the Mach4 software go to Configure=>Control=>Axis Mapping

Select which motor is the slave under Slave 1

Second: Configure=>Plugins=>HiCON

Select the motor that you want to be the master and uncheck the Independent Master-Slave Home and make sure that the index pulse is unchecked.

Select the motor that you want to be the slave and uncheck the Independent Master-Slave Home and make sure that the index pulse is unchecked.

Third: Configure=>Control=>Input Signals

Make sure that the slave axis home switch, Motor - and Motor + are disabled

Option B. Homing with Home/Limit switch on Master and Slave:

In the Mach4 software go to Configure=>Control=>Axis Mapping
Select which motor is the slave under Slave 1

Configure=>Control=>Inputs Signals
Make sure that the Slave axis home switch, Motor - and Motor + are Enabled.

Configure=>Plugins=>HiCON
Select the motor that you want to be the master and check the Independent Master-Slave Home and make sure that the index pulse is unchecked.

Select the motor that you want to be the slave and check the Independent Master-Slave Home and make sure that the index pulse is unchecked.

Set Slave Misalignment value if needed to "square" the gantry
https://support.machmotion.com/books/knowledge-base/page/aligning-slave-axis-gantry---mach4

Troubleshooting:

If there are motion issues with the homing, it is likely the axis designation does not match the homing switch designation. In other words, the homing switch assigned to the master axis is likely actually on the slave axis.
After touching off the switches, if one of the sides of the gantry continues to travel, "dragging" the other side along with it, would be an example of such motion issue caused by "swapped" configuration of switch assignments.
#######

This is the original site
https://support.machmotion.com/books/software/page/enable-slave-axis-in-mach4

Cheers

Hi Segio007. Sorry for the delay. I checked and what fixed my issue is having each homing switch on a different signal.  Doesn't look like I can post an image on my mobile device. I use a different controller but I think the function is the same within Mach4

Hi, thank you for your reply.

I contacted Poscope, who offer by the way an excellent support. The explained to me that each motor needs it own signal from limit switches. It doesn't matter that two motors are driving the same axis, the control board needs an input for each motor. In my case it is ok to wire the same limit switches to both motors, which I did and this fixed the issue.