Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: Kerry Harrison on July 08, 2008, 11:56:51 PM
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Greetings,
Is there any way to configure Mach3 to display 0.000 on all axis at start up?
Thanks,
Kerry
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Hi, Kerry
Un-check "Persistent DRO's" should do it.
Chip
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Kerry - That is a bit of a simplistic question.
Mach 3 keeps many values of DRO's in it's memory.
There are two you need to be concerned with - one is Machine Co-ordinates - the other is Program Co-ordinates.
Machine Co-ordinates are kept by Mach3 so it knows where the machine is. Machine Co-ordinates can only be zeroed by clicking the "Ref All Home" button. If you have home switches fitted and activated the machine then moves to these switches, and when it touches them it stops and zeros the DRO. If you do not have home switches activated, then clicking the "Ref All Home" button will zero the DROs wherever the machine happens to be.
Machine Co-ordinates are displayed when the Machine Co-ordinates button is lit (red ring round). If you press the button, the led goes out and the DRO displays Program Co-ordinates.
It is unlikely that machine co-ordinates provide a suitable location from which to start a program, and therefore offsets are provided G54 to G59 to "relocate" the 0.0.0 position from that used by Machine Co-ordinates to that used by your program. You can set these up if you wish, and include them in the program -
e.g. Ref All Home then in the program G54, G0X0Y0 would ref you machine to its Machine Co-ordinates, then change to the G54 offset, then move the table to the new 0.0 This is the way the professional machine shops start the day.
You can ignore that and jog you machine to a suitable 0.0.0. position, then manually zero all the axis for the start of your program.
Be aware, however, that the machine always operates in Machine Co-ordinates so this a) does not alter the Machine Co-ordinates position and b) it changes the G54 offset in the fixtures table to compensate.
I assume all you are wanting to do is start your machine up - presumably with the table in the correct position and have the DRO's zero themselves - ready to run the program. This is not good practice, although I can understand it.
For the moment I would (assuming you have no home switches operative), jog to your start position if needed, then click "RefAllHome" which will zero the Machine Co-ordinates. If you look at Program Co-ordinates make sure they are all zero as well (if not zero them). Your machine is then all zero with no offsets. I would then run in machine co-ordinates. If you keep "Persistant DRO's" on, this position will not change and if you go back to 0.0.0 the machine will always return to the same psoition.
I hope this is clear - it is a bit to get your head round at first. There is a video tutorial about offsets and things which is quite good.
If there is anything else - come back.
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Thanks jimpinder for a very clear explanation of this issue. It helped me a lot.
Regards,
Alan