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I think

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The homing position DRO value can be autoset with checking the checkbox next to the field.***[b] If the autoset checkbox is not set[/b]*** then the axis will remain it's coordinate when a homing sequence is successfully executed. ***[b]If the autoset checkbox is not set [/b]***then the set value will be written to the axis position DRO when a homing sequence is successfully executed.

The quote is direct copy of the user manual and the issue has three stars before and after the problem; the error appears to be NOT SET in both examples.

As a secondary question does it actually work like this:

If the auto set is not used then the values written will be the actual coordinates when a homing is done and successful?

If auto set is ticked then the values in the box will be written into the DRO; so if value is zero then when homed the value will be set to 0 automatically?

What difference does this make? I assume the values are written to the machine coordinates.....

If unchecked, the machine coordinates are not changed when homing.
Not sure why anyone would want this, as the homing process would no longer be setting a repeatable "home" position.

If checked, then yes, the value you entered becomes the home switch position after homing.

Yes, it is really a typo in the documentation, we will correct it.

The auto set checkbox could be used to verify the position. You could uncheck the checkbox (even programmatically from a macro) and then home the axis and check if you get the correct position to see if the machine lost any steps.
It could be also used to measure a home switch's repetability.

cncdrive wrote: You could uncheck the checkbox (even programmatically from a macro) and then home the axis and check if you get the correct position to see if the machine lost any steps.
It could be also used to measure a home switch's repetability.

So just to be clear. I home the three axis where I want home to be, zero the coordinates in machine coordinates to set home and press home all.

Then I move the axis to another place (uncheck the auto checkbox) and then press the go to zero and it should go down to zero if we don't lose any steps.

Move to the correct position if it loses steps and home again there and check the box again and find out why its losing steps.....

No homing switches yet.

Yes.
And in addition you could test how precise your home switches are with unchecking the auto set checkbox and homing the axis several times and compare the position DROs for each homing sequence.

So just to be clear. I home the three axis where I want home to be, zero the coordinates in machine coordinates to set home and press home all.

Not exactly.
You can't zero the machine coordinates. The Home All button does that.

Then I move the axis to another place (uncheck the auto checkbox) and then press the go to zero and it should go down to zero if we don't lose any steps.

Go To Zero goes to Work Coordinate Zero. So if you have any offsets set, zero may not be where you think it is. After homing, you should then zero all the axis, to clear the work offsets.

Not exactly.
You can't zero the machine coordinates. The Home All button does that

Yes, sorry that is what I meant.


So how do I send it to the home position? Can I? or must i jog there every time because don't have home switches. Or is that the little icon next to "go to zero"?

So how do I send it to the home position? Can I? or must i jog there every time because don't have home switches. Or is that the little icon next to "go to zero"?

You home with the Home buttons. They are the red buttons on the opposite side of the position DROs as where the Zero buttons are.
You can home all axis in sequence with the Home all button or you can home them individually with the axis home buttons.
For the homing ofcourse you have to setup a home port/pin, otherwise the axes will just set the home position without movement if the auto set checkbox is set otherwise if the auto set is not set then they will do nothing.
If the home port/pin is set to an input pin then the axis moves on the home switch and then reverses direction, moves off the switch and stops and sets the machine coord of the axis if the auto set chkbox is set otherwise it leaves the machine coord of the axis as it is.

No home switches on this system as in previous post.

What I was meaning was; Can I press a button to send the machine to its home postion or do I have to jog there after I have homed it and then moved to a work position.

i.e. I have homed the system

I then move to a work position and zero the axis x,y and z.

After I have finished I want to send the axis back to the home position whilst I setup for a different job. So can I just press a button to do that or do I have to jog each axis manually to the previously set home?

There are no home switches on my machine I don't need to save the work coordinates as I am cutting a different piece.

I understand that that go to zero sends to the work coordinates zero but can I get to the machine coordinate position zero easily using just a button?

When I homed the machine coordinates I set the coordinates by double clicking the home button for each individual axis. How does the programme differentiate between home zero on axis and work coordinates zero on all axis?

Ah Ah. to answer my own question its run a G28 command.

So the next question is how do I set a tool change position and run the M6 command? I would just need to move the z axis up and then y towards me and x to a reasonable place. I assume that the positions are offsets from machine coordinate zero (home zero) so it goes to the same place every time?

Or would it be simpler to have machine home as a tool change position (therefore just a G28 command) and set up my soft limits as - and + offsets on each axis from there?

Sorry for all the questions but I am a relative newby

Tony