Ref all Home sends X axis running off - indefinaltey

[larryreader]

Hello,
Recently when I hit ref all home the x axis takes off and does not stop until I kill it. It does this with or without my CNC machine (zenbot) turned on.
Anyone have an idea what could cause or how to fix ?
Thanks

[GRAYHIL]

I had a similar problem. When traversed it would not stop in the y axis till I hit emergency stop.
It was my fault I had put 4.00" instead of .004" into the y axis backlash.
Graham

[ger21]

DO you have home switches, and do they work?

[kregan]

I had the same problem for months.  I used my limit switches as home switches.  One
day I discovered I had my Y and X axis limit switches crossed at the break out board...
I never noticed it because the limit switches worked.  It was one of those hand to
 the forehead moments!!!

[larryreader]

Thanks for your replies
I do not have any home or limit switches, yet.
I will check the X axis backlash, but I had not been fiddling with such things when this started happening.
I'm Looking forward to that hand to forehead moment.

[Sargon]

Ref all home requires homing/limit switches to be installed. The axis will move until it finds the switch, so I believe the behaviour that you are seeing is normal. Of course, hitting the Stop button should cancel the homing operation.

To disable so it isn't accidentally triggered, you can use the "Edit Button Script" function under the Operator menu, then click the ref all home button. Add the command "End" without the quotes to the beginning of the script. When you have installed the switches you can then just remove this line using the same process and homing should work.

[larryreader]

Thanks Sargon, I'll dig into that, but makes me wonder why Ref all home did work initially. without homing/limit switches.

[larryreader]

I guess I should add that the technique I had been using was to manually set the router bit to home, then turn on the CNC drivers, then hitting ref all home would set all the axis to 0. I'm beginning to understand that Ref all home actually is for homing to home switches ?

[ger21]

Sounds like you have an X axis home switch enabled, even though you don't have a switch. If no switches are enabled (pins assigned), then it shouldn't move.

You can use Ref All without switches, and it should zero all the axis at there current position. Before I had home switches, I would jog the axis against hard stops and use Ref All. This gave me a repeatable home position, just like having switches.

[Sargon]

Ah, that makes sense. Thanks for clarifying - all my machines have homing switches, so I guess I was making an assumption.