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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
'I enjoy sex at 73.....I live at 71 so its not too far to walk.'
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.