So this is all a bit funky, but possibly i’m just unlucky and got 2 bad boards (one from the latest KS, one purchased as a spare).
Drop box link:
What those videos show:
- One Z-motor (the port closest the usb) intermittently doesn’t work. When it doesn’t work it either:
- Doesn’t start turning when the other motor does
- Doesn’t start turning when the other does but starts part way through the movement.
- As yet i’ve don’t think i’ve seen one stop partway through, and there is decent torque when it runs.
There’s four videos - 2 with the Maslow fully built, and 2 with the motors bare (quite useful for testing) like this:
In both cases, swapping the cables between ports swaps which motor exhibits this behaviour.
So far, so ‘it’s a bad board’.
Thing is, this happens with both boards I have - the spare board I tested with shows the same behaviour, and is straight out of its bag from posting. So maybe i’m unlucky and got two bad boards, or both motors have issues, or there’s something funkier going on here?
My original board is running 1.06, and I believe the recently received board is running 1.04:
@bar (or anyone else) - have you seen behaviour like this before?
I wonder if the motors could somehow be being driven so they are just hitting the edge of spec (I believe steppers can be finicky?), and whether there’s some way to test that - if we assumed we’re over/under voltage/current, can I tweak any settings slightly to test?
Probably not relevant, but I am in the UK so the power supply is running in 240V mode - shouldn’t matter but worth noting.
Looking at what’s in the Malsow.yaml, we have:
z:
steps_per_mm: 100.000000
max_rate_mm_per_min: 400.000000
acceleration_mm_per_sec2: 10.000000
max_travel_mm: 100.000000
soft_limits: false
homing:
cycle: -1
allow_single_axis: true
positive_direction: true
mpos_mm: 0.000000
feed_mm_per_min: 50.000000
seek_mm_per_min: 200.000000
settle_ms: 250
seek_scaler: 1.100000
feed_scaler: 1.100000
motor0:
limit_neg_pin: NO_PIN
limit_pos_pin: NO_PIN
limit_all_pin: NO_PIN
hard_limits: false
pulloff_mm: 1.000000
tmc_2209:
uart_num: 1
step_pin: gpio.15
direction_pin: gpio.16
disable_pin: NO_PIN
r_sense_ohms: 0.110000
run_amps: 1.000000
hold_amps: 0.500000
microsteps: 1
toff_disable: 0
toff_stealthchop: 5
use_enable: true
addr: 0
run_mode: StealthChop
homing_mode: StealthChop
stallguard: 0
stallguard_debug: false
toff_coolstep: 3
motor1:
limit_neg_pin: NO_PIN
limit_pos_pin: NO_PIN
limit_all_pin: NO_PIN
hard_limits: false
pulloff_mm: 1.000000
tmc_2209:
uart_num: 1
step_pin: gpio.46
direction_pin: gpio.38
disable_pin: NO_PIN
r_sense_ohms: 0.110000
run_amps: 1.000000
hold_amps: 0.500000
microsteps: 1
toff_disable: 0
toff_stealthchop: 5
use_enable: true
addr: 1
run_mode: StealthChop
homing_mode: StealthChop
stallguard: 0
stallguard_debug: false
toff_coolstep: 3
That appear to relate to the Z motors - i’m happy to tweak and test things and see what happens - I had wondered about boosting/lowering run_amps or hold_amps for the motor in question (not sure which motor is 0 which is 1)? Or maybe max_rate_mm_per_min or acceleration_mm_per_sec2 ?
