Problem with 0 at center

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This topic contains 9 replies, has 5 voices, and was last updated by  Tony 4 months ago.

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  • #83186

    Heath
    Participant

    I’ve been hoping to have more time to experiment and troubleshoot and figure this out on my own, but I haven’t had that time, so I’m throwing this out here.

    When I was making my daughter’s hot glue gun stand, I used the MPCNC to engrave a horse image on the front.  For this, the 0/0 location was at the center bottom of the image.  This was so I could zero the MPCNC at the center of the front edge of the board.  This worked out just fine.

    I also pocketed a square for a ceramic tile to catch the glue ooze.  For this, I set zero point in the center of the square.  I laid out the square on the board, zeroed the CNC at the center point of the square.  But this cut did not work so well.

    Every cut with a negative X or Y coordinate made a fast move from 0/0 to that coordinate, then back.  The positive X/Y coordinate movements were just as they should have been.  And the further out from center it got, the more aggressive the negative coordinate movement got.  It didn’t take long for me to shut it off. I just happened to be recording it as it was my first non-test project.

    To successfully make this pocket, I had to remake the gcode file with the zero point at the lower left so all coordinates were positive.  Why would one operation have handled negative coordinates just fine, but the other one spaz out?  I can’t think of any changes I made in Estlcam between operations, but maybe I’m forgetting something I did?

    #83190

    Ryan
    Keymaster

    That is something different all together. Are your LCD wires bundled with other wires? I have never seen that but looks like some sort of line noise or something.

    #83279

    Bill
    Participant

    Zip the gcode and attach it here. Maybe something in that will tell us what’s wrong. If it’s as Ryan suggests the gcode will be fine.

    #83303

    Heath
    Participant

    No, the LCD wires aren’t bundled with anything else.  I do think it was something with the file.  I haven’t had any kind of issue like this since, but I haven’t tried setting 0 anywhere but the lower left so all coordinates would be positive.  Unfortunately, when I re-created the file I saved it as the same file name so can’t go back and examine that gcode file.

    I thought each negative movement was going to X0/Y0 like spokes on a wheel, but watching it closer now it’s only doing that in quadrant 3 (X-/Y-).  In quadrant 1 (X+/Y+) it behaves normally.  In quadrant 2 (X-/Y+) it is making horizontal movements perpendicular to the Y axis.  In quadrant 4 (X+/Y-) it is making vertical movements perpendicular to the X axis.  So it’s like it only has a problem with whichever coordinate is negative and has to go back to 0 location for that particular axis after each movement.  Movement in quadrant 3 was particularly problematic since both axis were negative.

    #88716

    MegaDad3D
    Participant

    I thought each negative movement was going to X0/Y0 like spokes on a wheel, but watching it closer now it’s only doing that in quadrant 3 (X-/Y-).  In quadrant 1 (X+/Y+) it behaves normally.  In quadrant 2 (X-/Y+) it is making horizontal movements perpendicular to the Y axis.  In quadrant 4 (X+/Y-) it is making vertical movements perpendicular to the X axis.  So it’s like it only has a problem with whichever coordinate is negative and has to go back to 0 location for that particular axis after each movement.  Movement in quadrant 3 was particularly problematic since both axis were negative.

    I got that problem when I had negative X and negative Y values in the same gcode file, although it happened both in quadrant 3 (X- Y-) and also quadrant 4 (X- Y+)

    #88720

    Heath
    Participant

    I thought each negative movement was going to X0/Y0 like spokes on a wheel, but watching it closer now it’s only doing that in quadrant 3 (X-/Y-). In quadrant 1 (X+/Y+) it behaves normally. In quadrant 2 (X-/Y+) it is making horizontal movements perpendicular to the Y axis. In quadrant 4 (X+/Y-) it is making vertical movements perpendicular to the X axis. So it’s like it only has a problem with whichever coordinate is negative and has to go back to 0 location for that particular axis after each movement. Movement in quadrant 3 was particularly problematic since both axis were negative.

    I got that problem when I had negative X and negative Y values in the same gcode file, although it happened both in quadrant 3 (X- Y-) and also quadrant 4 (X- Y+)

    I had a problem in all 3 quadrants with negative values.  I think I was describing the specifics of the movement.
    Quadrant 1 (X+/Y+): normal behavior
    Quadrant 2 (X-/Y+): Horizontal movement only on X axis.  It only moved in the Y axis at X0.
    Quadrant 3 (X-/Y-): Diagonal movement from X0/Y0 out to negative coordinates and back to X0/Y0.
    Quadrant 4 (X+/Y-): Vertical movement only on Y axis. It only moved in the X axis at Y0.

    I’m not sure that is relevant to anything, just something I noticed after my initial post.  This was a correction to my initial statement that all of the movement in the “negative” quadrants was straight back and forth from X0/Y0.

    #88788

    Ryan
    Keymaster

    The dual firmware will not do negative movements in XY.

    2 users thanked author for this post.
    #89416

    Tony
    Participant

    The dual firmware will not do negative movements in XY.

    So if some guy like me ordered dual endstops and both sets of wiring with the intention of following the advice “learn the machine without the stops, then add the stops later” he would get the board with the dual firmware and have similar issues? Because that’s what’s happening over here, too.

    #89424

    Ryan
    Keymaster

    So if some guy like me ordered dual endstops and both sets of wiring with the intention of following the advice “learn the machine without the stops, then add the stops later” he would get the board with the dual firmware and have similar issues? Because that’s what’s happening over here, to

    You can check what firmware is on the board by running an m119 from repetier, if there are any y2 or x2 showing you have dual, on the other hand if you have non-dual and plugged in the endstops you would get the same results.

    #89430

    Tony
    Participant

    yup, it’s all there. I thought I was going to have to flash that firmware later. Guess I’m good to go, as long as stop trying to make negative moves!!

    Thanks.

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