DROs reading negative

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tas99
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DROs reading negative

Post by tas99 »

I’m in the finishing stages of my DIY plasma cutter.

I have all the motors working and homing but when I move either the X or Y off of home the DROs show a negative direction. I believe they should be reading positive movement off of home. It’s probably something simple but I can’t find it.

Any help would be appreciated.

Tom
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FabLab
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Re: DROs reading negative

Post by FabLab »

What corner of your machine is home? If home is the upper right (or NorthEast) then moving from home would be a negative direction
tas99
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Re: DROs reading negative

Post by tas99 »

My table is set up as shown in the attached image.

I found that if I go to Config/Motor Outputs and enable the Dir Low Active the readings are correct as the head moves away from the home position but with that setting it homes in the wrong direction.

Axis Direction.JPG
tas99
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Re: DROs reading negative

Post by tas99 »

Sorry, I meant to add X is in the red direction and Y in the green.
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FabLab
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Re: DROs reading negative

Post by FabLab »

That is unusual setup(at least to me) in that configuration to move from home X would be + and Y would be -

Normally X would be the green direction and Y would be the red direction and home would be in the lower left corner of your drawing.
You can set it up however you want, it doesn't really matter but I would suggest at least setting up the green direction as X and red as Y.

All of the tables I have worked with have home in the lower left and X as the green direction and Y as red that way moving from home is always +

What might help is to Google CNC three finger rule

hope that helps!
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djreiswig
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Re: DROs reading negative

Post by djreiswig »

If you rotate your picture 90 degrees clockwise that is how my table is set up. Home is lower left. X moves left to right and y moves top to bottom. I'll have to see what my Mach3 settings are.
2014 Bulltear (StarLab) 4x8
C&CNC EtherCut
Mach3, SheetCam, Draftsight
Hypertherm PM65
Oxy/Acetylene Flame Torch
Pneumatic Plate Marker, Ohmic, 10 inch Rotary Chuck (in progress)
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djreiswig
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Re: DROs reading negative

Post by djreiswig »

I think there is a setting to tell it which way to home the axes. It's different from the motor output setting.
Look in config/homing & limits. Change the home neg setting. It should home the opposite direction.
2014 Bulltear (StarLab) 4x8
C&CNC EtherCut
Mach3, SheetCam, Draftsight
Hypertherm PM65
Oxy/Acetylene Flame Torch
Pneumatic Plate Marker, Ohmic, 10 inch Rotary Chuck (in progress)
tas99
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Re: DROs reading negative

Post by tas99 »

That did it!!!

The Home Neg was enabled for the X and Y axis. Not sure why but they were and once unchecked it all worked as expected.

Thanks for everyone's help. It's much appreciated.

Tom
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djreiswig
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Re: DROs reading negative

Post by djreiswig »

Great to hear. Happy to help.
2014 Bulltear (StarLab) 4x8
C&CNC EtherCut
Mach3, SheetCam, Draftsight
Hypertherm PM65
Oxy/Acetylene Flame Torch
Pneumatic Plate Marker, Ohmic, 10 inch Rotary Chuck (in progress)
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