1. Got a question or need help troubleshooting? Post to the troubleshooting forum or Search the forums!

Partially Solved Calibrating seems to be off on Y axis

Discussion in 'Troubleshooting' started by Mike Glass, Dec 31, 2014.

Page 1 of 2
  1. Mike Glass

    Mike Glass Active Member

    Joined:
    Dec 29, 2014
    Messages:
    268
    Likes Received:
    123
    I noticed when the printer does calibration it does not stay within the square lines on the hotbed, I also notices that it prints up farther back on the bed not in the middle.
     
    #1 Mike Glass, Dec 31, 2014
  2. anmael

    anmael New Member

    Joined:
    Dec 30, 2014
    Messages:
    18
    Likes Received:
    5
    i had the same problem, try turning with your hands the two metal rods that control the y-axis in the same direction until the holes on the bottom of both rods point in the same direction, then re-do the calibration through software...
    basically your y-axis is slanted right now.

    Note: i am very new at this and just got my robo3d r1 yesterday, this was just my impression and my solution, there may be better ways
     
    #2 anmael, Dec 31, 2014
  3. Mike Glass

    Mike Glass Active Member

    Joined:
    Dec 29, 2014
    Messages:
    268
    Likes Received:
    123
    You are referring to the Z axis, I just got my printer this week also and had to adjust the bed as it was slanted, switches turned and wires that were not plugged into the ardrino board, but I am talking about the forward and back of the bed. I think I may have figured it out, I just powered it up and moved the belt on the bed to the most forward position.
    Kinda strange that the micro switch does not stop the bed from going to far and makes a horrible sound.
     
    #3 Mike Glass, Dec 31, 2014
  4. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    23,915
    Likes Received:
    7,338
    You need to check the Y belt drive. That could be a symptom that the belt as it moves back and forth in the Y travel is binding on one of the pulleys/pinions. For me this happened because the gear on the Y drive motor shaft was too low on the shaft and needed too be shifted up a fraction of an inch.

    Take the bed off and move the rails in the Y axis back and forth. Watch the belt as it travels over the pinions in the center and make sure it stays in the center of these and does not move up/down as the belt moves back and forth. If it binds on a pinion it will stop moving and you will hear the motor grind on the belt drive... it basically binds and stops moving just before the microswitch can be made/activated.

    Something is binding it, that is what made mine bind up -- yours may be different, but at least you know what to look at.
     
    #4 mark tomlinson, Dec 31, 2014
  5. Mike Glass

    Mike Glass Active Member

    Joined:
    Dec 29, 2014
    Messages:
    268
    Likes Received:
    123
    Just started another print and it re-calibrated and started an inch or so off like before, is this in the software?
    Can somebody tell me when the calibration happens does it stay within the defined square, as mine does not.
    Thanks
     
    #5 Mike Glass, Dec 31, 2014
  6. Mike Glass

    Mike Glass Active Member

    Joined:
    Dec 29, 2014
    Messages:
    268
    Likes Received:
    123
    Can somebody tell me their print center configuration, mine is set at 114 127.
     
    #6 Mike Glass, Jan 1, 2015
  7. Tanbam

    Tanbam Member

    Joined:
    Dec 20, 2014
    Messages:
    84
    Likes Received:
    28
    That is my center setting, too. Mine prints in the center of the bed.
     
    #7 Tanbam, Jan 1, 2015
  8. Tanbam

    Tanbam Member

    Joined:
    Dec 20, 2014
    Messages:
    84
    Likes Received:
    28
    When I was working with getting my auto level working consistently, Ziggy helped me with a couple of tweaks to my Start G-Code to make it run better. Perhaps this may help you, too.

    My Custom G-Code Start G-Code is the following:

    M109 S(temperature) ; set the extruder temperature
    G28 X0 Y0 ; move the extruder to the front left corner
    G28 Z0 ; touch the bed
    G1 Z5 E5000 ; lift nozzle
    G28 Z0 ; touch the bed again in case there is any filament on the nozzle
    M565 Z0 ; not sure what this is for
    G29 ; probe the bed

    With this start code, my printer has been very consistent with the positioning.
     
    #8 Tanbam, Jan 1, 2015
  9. Mike Glass

    Mike Glass Active Member

    Joined:
    Dec 29, 2014
    Messages:
    268
    Likes Received:
    123
    Using that code it just sits and waits for the extruder to warm up and nothing happens. no matter what I do it is an inch off towards the back, as for now I am moving the pieces up front and unchecking center on bed.
     
    #9 Mike Glass, Jan 2, 2015
  10. k1e1v1i1n

    k1e1v1i1n Active Member

    Joined:
    Dec 11, 2014
    Messages:
    230
    Likes Received:
    73
    Same for me I have been moving prints forward but I will have to look into fixing this some time.
     
    #10 k1e1v1i1n, Jan 2, 2015
  11. Mike Glass

    Mike Glass Active Member

    Joined:
    Dec 29, 2014
    Messages:
    268
    Likes Received:
    123
    Yea pain in the butt, and I have to heat the bed and extruder before I print or it will not calibrate.
     
    #11 Mike Glass, Jan 3, 2015
  12. Mike Glass

    Mike Glass Active Member

    Joined:
    Dec 29, 2014
    Messages:
    268
    Likes Received:
    123
    I switched to Cura and seems to place it correctly on the bed, yay.
     
    #12 Mike Glass, Jan 11, 2015
  13. k1e1v1i1n

    k1e1v1i1n Active Member

    Joined:
    Dec 11, 2014
    Messages:
    230
    Likes Received:
    73
    I am using Cura now also and I am still back a good bit and a little to the right.
     
    #13 k1e1v1i1n, Jan 11, 2015
  14. Mike Glass

    Mike Glass Active Member

    Joined:
    Dec 29, 2014
    Messages:
    268
    Likes Received:
    123
    Here is my gcode. I noticed my printer does not extrude as the code states, is this because it is backwards on the print gui.

    G21 ;metric values
    G90 ;absolute positioning
    M82 ;set extruder to absolute mode
    M107 ;start with the fan off
    G28 ;Home All
    M565 Z-.5 ; Define 1.0mm of offset, adjust this value if you're too high/low. More negative is further from the bed
    G92 E0 ;Reset Extruder count
    G1 E-5.0 ;Retract 5mm for probing to limit dots
    G29 ; Run autolevel routine
    G1 Z15.0 F{travel_speed} ;move the platform down 15mm
    G92 E0 ;zero the extruded length
    G1 F200 E3 ;extrude 3mm of feed stock
    G92 E0 ;zero the extruded length again
    G1 F{travel_speed}
    ;Put printing message on LCD screen
    M117 Printing...
     
    #14 Mike Glass, Jan 11, 2015
  15. Mike Kelly

    Mike Kelly Volunteer

    Joined:
    Mar 11, 2013
    Messages:
    6,967
    Likes Received:
    2,277
    You're retracting 5 the only extruding 3. Remove the g92 after retraction.
     
    #15 Mike Kelly, Jan 11, 2015
  16. Just Kelly

    Just Kelly New Member

    Joined:
    Feb 15, 2016
    Messages:
    16
    Likes Received:
    4
    My Y center is a bit off as well. Not usually a problem, but I'm doiong some longer pritns lately and so I wind up with one end hanging over the heated area and the otehr end with plenty of room to spare. Kind of annoying, as you can imagine. My center is 114,127 like the others in this thread, but I'm thinking of seeing what happens if I move the center Y coordinate. Is that a good solution?
     
    #16 Just Kelly, Mar 18, 2016
  17. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,905
    Likes Received:
    3,593
    The white square is not where the heated area is actually installed, it is a bit further to the rear of the printer. Plus the heater only covers about 67% of the actual travel area of the hotend.

    Bed center is determined by the endstop switches which are at the minimum positions of X and Y. So the printer knows exactly where X0 and Y0 are and that just doesn't line up with the white square. With X0 and Y0 known the firmware actually calculates the center of the build platform, you can't really tell it where it is without modifying Marlin firmware.
     
    #17 WheresWaldo, Mar 18, 2016
  18. Just Kelly

    Just Kelly New Member

    Joined:
    Feb 15, 2016
    Messages:
    16
    Likes Received:
    4
    It doesn't, huh? Color me surprised. Well, still getting the occasional bit of lift when it goes across the line, but I suppose I can just brim it and it should be all right. Thanks for letting me know.
     
    #18 Just Kelly, Mar 19, 2016
  19. Jeff Ortakales

    Jeff Ortakales New Member

    Joined:
    Apr 2, 2016
    Messages:
    10
    Likes Received:
    1
    I'm running into this same issue and I don't believe that this is correct. If I look under the print bed I can see that the heated area lines up quite closely with the white outline. The print I'm running right now is about 1" outside of the lines even though it should be within them. Also, when I manually move the bed in the Y- direction, it will hit the limit switch and nothing happens however, when I move it in the Y+ direction, it keeps going until I hear a grinding noise. This makes me think that it doesn't really know the correct Y0 location.
     
    #19 Jeff Ortakales, Apr 13, 2016
  20. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,905
    Likes Received:
    3,593
    @Jeff Ortakales
    Are you speaking about the cork that is taped over the heater. I can say definitively say that the heater is only 2/3's of the printable area. I can also tell you definitively that the endstop determines what Y0 is and if you are using the default firmware the center is Y254/2. Marlin figures it out mathematically. This is how Robo defines their own printer (excerpt of Marlin code follows)
    Code:
    // Travel limits after homing
#define X_MAX_POS 240
#define X_MIN_POS 0
#define Y_MAX_POS 254
#define Y_MIN_POS 0
#define Z_MAX_POS 240
#define Z_MIN_POS 0
    Here is how Marlin defines the center point
    Code:
        #define Z_SAFE_HOMING_X_POINT (X_MAX_LENGTH/2)    // X point for Z homing when homing all axis (G28)
    #define Z_SAFE_HOMING_Y_POINT (Y_MAX_LENGTH/2)    // Y point for Z homing when homing all axis (G28)
    Now since the Robo actually can't move a full 254mm on the Y axis then the center will be skewed slightly toward the back side, but in my measurements it was only about 5-6 mm. Now here is where it gets tricky. Placement by gcode is almost totally dependent on Slicer settings. So it you are using Robo's choices in MatterControl, it uses the same numbers Marlin already knows about which max out at 240 x 254 x 240 (X / Y / Z). All slicers use their own numbers to determine what the center of the bed is. All use the numbers in their particular configuration for mathematically determining the center of the bed. Since Robo published 240 x 254 x 240, that is what most slicers use.

    Since it is electrically impossible to go beyond Y0 as there is a physical switch. The printer always knows where Y0 is (in fact it knows where every axis 0 point is). The problem comes from the fact that Robo doesn't actually know how far their bed can move. Marketing says it is better to say 9 x 10 x 8. It isn't 240 x 254 x 240, that is why you have grinding on the back end. Nothing at all to do with the 0 points.

    Again the heater does not cover the entire print bed, period.
     
    #20 WheresWaldo, Apr 13, 2016
    Last edited: Apr 13, 2016
    aenea22980 and mark tomlinson like this.
Page 1 of 2

Share This Page