Problem: Table pulling out of square after homing

[Davinjw]

Wiki Search Terms

pulloff pull off homing ganged square

Controller Board

MKS Tinybee

Machine Description

laser table, ganged Y axis and single X axis motor

Input Circuits

No response

Configuration file

board: MKS TinyBee V1.0_001
name: K40 Laser
meta: (01.02.2022) by Skorpi

kinematics:
  Cartesian:

stepping:
  engine: I2S_STATIC
  idle_ms: 0
  pulse_us: 4
  dir_delay_us: 1
  disable_delay_us: 0

axes:
  y:
    # Y
    steps_per_mm: 40.000
    max_rate_mm_per_min: 18000.000
    acceleration_mm_per_sec2: 1500.000
    max_travel_mm: 800.000
    soft_limits: true
    homing:
      cycle: 2
      positive_direction: false
      mpos_mm: 0.000
      feed_mm_per_min: 300.000
      seek_mm_per_min: 2000.000
      settle_ms: 500
      seek_scaler: 1.100
      feed_scaler: 1.100

    motor0:
      limit_neg_pin: gpio.33
      hard_limits: true
      pulloff_mm: 2.000
      stepstick:
        step_pin: I2SO.1
        direction_pin: I2SO.2
        disable_pin: I2SO.0

    motor1:
    #E0
      limit_neg_pin: gpio.35
      hard_limits: true
      pulloff_mm: 2.000
      stepstick:
        step_pin: I2SO.10
        direction_pin: I2SO.11:low
        disable_pin: I2SO.9

  x:
    # X
    steps_per_mm: 40.000
    max_rate_mm_per_min: 12000.000
    acceleration_mm_per_sec2: 300.000
    max_travel_mm: 628.650
    soft_limits: true
    homing:
      cycle: 1
      positive_direction: false
      mpos_mm: 0.000
      feed_mm_per_min: 300.000
      seek_mm_per_min: 5000.000
      settle_ms: 500
      seek_scaler: 1.100
      feed_scaler: 1.100

    motor0:
      limit_neg_pin: gpio.32
      hard_limits: true
      pulloff_mm: 2.000
      stepstick:
        step_pin: I2SO.4
        direction_pin: I2SO.5
        disable_pin: I2SO.3

#  z:
#    # Z
#   steps_per_mm: 157.750
#    max_rate_mm_per_min: 12000.000
#    acceleration_mm_per_sec2: 500.000
#    max_travel_mm: 80.000
#    soft_limits: true
#    homing:
#      cycle: 0
#      positive_direction: false
#      mpos_mm: 0.000
#      feed_mm_per_min: 300.000
#      seek_mm_per_min: 1000.000
#      settle_ms: 500
#      seek_scaler: 1.100
#      feed_scaler: 1.100

#    motor0:
#      limit_neg_pin: gpio.22
#      hard_limits: false
#      pulloff_mm: 1.000
#      stepstick:
#        step_pin: I2SO.7
#        direction_pin: I2SO.8
#        disable_pin: I2SO.6




#  b:
#    # E1
#    steps_per_mm: 157.750
#    max_rate_mm_per_min: 12000.000
#    acceleration_mm_per_sec2: 500.000
#    max_travel_mm: 80.000
#    soft_limits: true
#    homing:
#      cycle: 0
#      positive_direction: false
#      mpos_mm: 0.000
#      feed_mm_per_min: 300.000
#      seek_mm_per_min: 1000.000
#      settle_ms: 500
#      seek_scaler: 1.100
#      feed_scaler: 1.100
#
#    motor0:
#      limit_neg_pin: gpio.2
#      hard_limits: false
#      pulloff_mm: 1.000
#      stepstick:
#        step_pin: I2SO.13
#        direction_pin: I2SO.14
#        disable_pin: I2SO.12

i2so:
  bck_pin: gpio.25
  data_pin: gpio.27
  ws_pin: gpio.26

spi:
  miso_pin: gpio.19
  mosi_pin: gpio.23
  sck_pin: gpio.18

sdcard:
  cs_pin: gpio.5
  card_detect_pin: NO_PIN

control:
  safety_door_pin: NO_PIN
  reset_pin: NO_PIN
  feed_hold_pin: NO_PIN
  cycle_start_pin: NO_PIN
  # EXP1 BTN_ENC
  macro0_pin: gpio.4:low:pu
  macro1_pin: NO_PIN
  macro2_pin: NO_PIN
  macro3_pin: NO_PIN

macros:
  startup_line0:
  startup_line1:
  macro0: $SD/Run=lasertest.gcode
  macro1: $SD/Run=home.gcode
  macro2:
  macro3:

coolant:
  flood_pin: gpio.2:low
  mist_pin: NO_PIN
  delay_ms: 0

#probe:
#  pin: NO_PIN
#  check_mode_start: true

Laser:
  pwm_hz: 5000
  # EXP1 BTN_ENC
  output_pin: gpio.13
  # FAN1
  enable_pin: I2SO.16
  disable_with_s0: false
  s0_with_disable: false
  tool_num: 0
  speed_map: 0=0.000% 0=12.500% 1700=100.000%
# 135=0mA 270=5mA 400=10mA 700=16mA
user_outputs:
  analog0_pin: NO_PIN
  analog1_pin: NO_PIN
  analog2_pin: NO_PIN
  analog3_pin: NO_PIN
  analog0_hz: 5000
  analog1_hz: 5000
  analog2_hz: 5000
  analog3_hz: 5000
  digital0_pin: NO_PIN
  digital1_pin: NO_PIN
  digital2_pin: NO_PIN
  digital3_pin: NO_PIN

start:
  must_home: false

 # USB  TX0(1)  RX0(3)
 # J3-> TX2(17) RX2(16)
 # J1-> I2SO.23 I2SO.22
 # TH1(36)        TH2(34)        THB(39)
 # HE0(I2SO.17)   HE1(I2SO.18)   HBED(I2SO.16)
 # FAN1(I2SO.19)  FAN2(I2SO.20)
 #                   EXP1                                   EXP2
 #(BEEPER) I2SO.21 | 1  2 | 13 (BTN_ENC)    (SPI MISO) 19 | 1  2 | 18 (SPI SCK)
 #    (LCD_EN)  21 | 3  4 |  4 (LCD_RS)      (BTN_EN1) 14 | 3  4 |  5 (SPI CS)
 #    (LCD_D4)   0 | 5  6   16 (LCD_D5)      (BTN_EN2) 12 | 5  6   23 (SPI MOSI)
 #    (LCD_D6)  15 | 7  8 | 17 (LCD_D7)      (SPI_DET) 34 | 7  8 | RESET
 #             GND | 9 10 | 5V                        GND | 9 10 | 3.3V

Startup Messages

I'm not at the table and can't pull these right now.

User Interface Software

No response

What happened?

If I home the machine, X homes correctly, Y homes correctly, then immidiately following this one of the ganged Y motors moves in the positive direction a couple millimeters while the second does not.

GCode File

No response

Other Information

No response

[bdring]

Your frame is probably naturally out square. The homing process squares it, but when the motors disable it might pop back to the out of square position. It is probably just moving the easiest side.

Change the idle_ms: value to 255. This will keep the motors enabled at all times.

http://wiki.fluidnc.com/en/config/axes#stepping