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Homing Question
« on: March 25, 2017, 09:43:40 PM »
My Z home switch location is located about 6 inches below the maximum Z axis travel. Sometimes my program ends with the Z axis stopping above the home position. If I start the machine the next day and I home the Z axis and forget to lower the Z to below the home position, the head travels up to the top until it trips the over travel. Is there a way to offset the Z home position to the top of the travel so this problem will not happen?
Re: Homing Question
« Reply #1 on: March 25, 2017, 10:53:11 PM »
Hi,
not as far as I know. On the Config/Homing-Limits page there is a check space to indicate which direction you wish an axis to travel
in order to trigger a home switch. If you start homing when already passed the home switch you're in trouble, it will go in the direction
you nominated until either a limit is hit or crash!

Is it possible to shift your home switch? My home switches are just a mm or two from the limit and I find it convenient. The setup you
have will put your machine zero between your limits so your machine co-ords will range from some negative value to positive. I would
find that situation confusing and confusion is by far and away the biggest cause of crashes.

Craig
My wife left with my best friend...
     and I miss him!
Re: Homing Question
« Reply #2 on: March 25, 2017, 10:55:49 PM »
Craig,
I was hoping I could avoid moving the switch, but it is probably the best answer. Thank you.

Offline ger21

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Re: Homing Question
« Reply #3 on: March 26, 2017, 10:37:01 AM »
Configure the switch to also act as a limit switch, and you should never go above it.
Gerry

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

JointCAM Dovetail and Box Joint software
http://www.g-forcecnc.com/jointcam.html
Re: Homing Question
« Reply #4 on: March 26, 2017, 01:23:11 PM »
Hi,
If I do that, I would not be able to use the full travel of the Z axis when machining.

Offline ger21

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Re: Homing Question
« Reply #5 on: March 26, 2017, 02:45:58 PM »
Then why is your home switch located where it is?
Gerry

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

JointCAM Dovetail and Box Joint software
http://www.g-forcecnc.com/jointcam.html
Re: Homing Question
« Reply #6 on: March 26, 2017, 02:48:37 PM »
It was positioned that way when I got the machine. I increased the Z travel using a longer support strut.