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Auto Squaring Gantry
« on: November 12, 2013, 10:13:31 PM »
Hi All,

I'm a bit confused....

I have a 3 Axis Router table, with a Slave on the X Axis (2 drives on ball-screws), controlled through an Ethernet Smooth Stepper & BOB
At present, I only have 1 home switch on the X Axis, but am trying to upgrade to 2, so I can auto-square the gantry.

I have found several threads here, but have not worked out how to "start" getting Mach3 to home & correct the slave axis.

I’ve obviously missed a step somewhere

Thanks in advance

Drew

Offline ger21

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Re: Auto Squaring Gantry
« Reply #1 on: November 12, 2013, 11:09:45 PM »
You need two switches for Mach3 to square the gantry for you. You basically just set up the home switches in Ports and Pins for both the Master (X) and Slave axis (A?), and when you home, each side should home independently to their own switch. You need to make sure to UNCHECK "Home Slave with Master" in General Config. You may also need to modify your Ref All script to use RefCombination() to get the two sides to move together.

However, I've heard from several people that auto squaring slaved motors doesn't work correctly with the ESS. I've never used one, so I can't confirm that. There is apparently some type of workaround. You might want to contact Greg at Warp9 to see if there are any issues.
Gerry

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http://www.thecncwoodworker.com/2010.html

JointCAM Dovetail and Box Joint software
http://www.g-forcecnc.com/jointcam.html
Re: Auto Squaring Gantry
« Reply #2 on: November 12, 2013, 11:17:06 PM »
Thanks for the quick reply  :)

Will have to modify my limit switch so I can fine-tune its position.
(Its close, but not perfect)

Offline rdean

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Re: Auto Squaring Gantry
« Reply #3 on: November 13, 2013, 06:32:02 AM »
I am using the ethernet smooth stepper for squaring my gantry with no problems.

Ray

Offline Chaoticone

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Re: Auto Squaring Gantry
« Reply #4 on: November 13, 2013, 09:37:50 AM »
Thanks for the quick reply  :)

Will have to modify my limit switch so I can fine-tune its position.
(Its close, but not perfect)

You can set a home off distance in your homing and limits and modify the homing script to adjust the gantry for you. This can get a little bit tricky if your using soft limits. You would set the home off distance to whatever the gantry is out by and have the axis move to zero when it has finished its homing routine.
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Re: Auto Squaring Gantry
« Reply #5 on: November 13, 2013, 04:23:40 PM »
Gerry,
Was wondering, does your method home X then Slave Axis? Or actually moves X & Slave together while homing?
If it does them seperatly, that could be a major problem, and need to look into finding a good script


Ray,
Are you using any script? If so, any chance you could post it here :))
Any chance of a video of the sequence ? (long shot I know)


To All,
Hope to give all this another test over the weekend, so any extra info will be greatfull


Thanks to all

Drew

Offline ger21

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Re: Auto Squaring Gantry
« Reply #6 on: November 13, 2013, 06:01:21 PM »
Yes, the normal method moves both axis at the same time, each to their own switch.
Gerry

2010 Screenset
http://www.thecncwoodworker.com/2010.html

JointCAM Dovetail and Box Joint software
http://www.g-forcecnc.com/jointcam.html

Offline rdean

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Re: Auto Squaring Gantry
« Reply #7 on: November 13, 2013, 08:23:42 PM »
I don't have a video but this is the way it works for me.

Z axis moves up or positive until it hits the limit switch and then reverses back down until off the switch.

Y axis moves in the negative direction until it hits the limit switch then reverses positive until it is off the switch.

X and B axis move in the negative direction together until one of them hits its limit and both motors stop.  The side that hit the limit first moves in the positive direction until it is off the switch.  Then the other side starts moving negative again until it hits its limit switch and then stops and reverses to get off the switch.  (This sequence is dependent on which side hits its limit first)
This is the Ref All Home script that I am using and it sets the work and machine coordinates to "0"

DoButton( 24 )
DoButton( 23 )
DoButton( 22 )
DoButton( 26 )

DoOEMButton(133)
DoOEMButton(134)
DoOEMButton(135)

Notice here I am slaving the X and B axis together.  If you ever plan on running a rotary axis it has to be designated as the "A" axis for the rotational feed rate to work so  
I would suggest you set up your slave drive as "B" now to save problems later.

In the ESS setup screen under "Noise Filtering of Inputs" you may have to set a debounce time for the "Limits" and "Home" boxes to make it work properly.  
The ESS controls the debounce now not Mach3.  (Mine are set to 5 in each)

You should already have the "Motor Home/Soft Limits" ( this is where you set the ref speed and distance the drive reverses off the switch)  set up in Mach3 before running the script.
Each of my axis have their own limit switch and are on separate inputs.

I probably have forgotten something since it has been 2 years since I set mine up but it would be a good idea to "Step" through the script one line at a time for safety.

Ray


DoOEMButton(135)
Re: Auto Squaring Gantry
« Reply #8 on: November 13, 2013, 08:30:40 PM »
Thanks Ray,
That makes sense :)
Re: Auto Squaring Gantry
« Reply #9 on: December 21, 2015, 09:53:45 AM »
You need two switches for Mach3 to square the gantry for you. You basically just set up the home switches in Ports and Pins for both the Master (X) and Slave axis (A?), and when you home, each side should home independently to their own switch. You need to make sure to UNCHECK "Home Slave with Master" in General Config. You may also need to modify your Ref All script to use RefCombination() to get the two sides to move together.

However, I've heard from several people that auto squaring slaved motors doesn't work correctly with the ESS. I've never used one, so I can't confirm that. There is apparently some type of workaround. You might want to contact Greg at Warp9 to see if there are any issues.

Hi Ger21, I'm having a problem with this. When I uncheck home slave with master and save it when I come back it is always checked again.
Has anyone here used the bathmate from this site or not?