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Author Topic: G28 Overshoot  (Read 4623 times)

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Re: G28 Overshoot
« Reply #10 on: December 28, 2009, 11:21:36 AM »
When homing, I manually jog at full speed to within an inch or so from the switch, then let mach home the axis from there.
Fastest way I know of, if the axis knows not where it is.

In "Homing / Limits" you can set the speed up a bit, but then check for consistency.
Ray has a cool macro for probing that could possibly be incorporated into the reference button where it HOMES once fast, then again slowly for greater precision and accuracy/repeatably.

Are you using servos by chance with a closed following loop ?
Some of them allow an amount of overshoot that can give you a similar problem.


Russ

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Re: G28 Overshoot
« Reply #11 on: December 28, 2009, 11:29:52 AM »
You can home each axis individually if you wish, buttons are on the Diagnostics page but you could modify your screenset and put them on the main page if you wanted.
There is no way to move faster than what you have as the homing speed. Reason is because until you have homed Mach doesnt  know where you are so how would it know how to go to the slower speed.
You could manually jog until close then press the Ref All  button.

Some people have altered the RefAll button to include a G53G0X*Y*Z* move before the actual homing move but this relies on the last homing move you did still being accurate and the table not being moved while switched off and to me it is not safe practice but thats just my opinion. Maybe I am just used to heavy powerful machines but still not something I would like to do.

Hood