Hi. I am setting up a creality laser module, which i have transplanted onto a Wanhao I3 3D printer. I have everything set up, and am able to JOG the laser head around just fine, but i cannot get the thing to home.
When i do home, It seems to move about 1cm towards home, then stops, beeps twice at me, and throws the following error:
ALARM:8
Homing fail. Cycle failed to clear limit switch when pulling off. Try increasing pull-off setting or check wiring.
ALARM:3
Reset while in motion. Grbl cannot guarantee position. Lost steps are likely. Re-homing is highly recommended.
ok
spindle_pwm_off_value:0.000000 spindle_pwm_min_value:0.000000 spindle_pwm_max_value:1023.000000
Grbl 1.3a ['$' for help]
[MSG:'$H'|'$X' to unlock]
[MSG:Caution: Unlocked]
ok
If i move the laser head into home manually, and then press home, It seems to move away from the home point, and then back into home twice. which is what i would expect a homing procedure to do when it is already at home.
So it seems that the machine is just giving up after trying to home for 1 cm.
I am using Normally Open switches.
Anybody have any advice, or any further info which i can provide? I have been scouring google, but am absolutely fresh into the lasering world.
the bits that matter $26 - Homing debounce, milliseconds Whenever a switch triggers, some of them can have electrical/mechanical noise that actually ‘bounce’ the signal high and low for a few milliseconds before settling in. To solve this, you need to debounce the signal, either by hardware with some kind of signal conditioner or by software with a short delay to let the signal finish bouncing. Grbl performs a short delay, only homing when locating machine zero. Set this delay value to whatever your switch needs to get repeatable homing. In most cases, 5-25 milliseconds is fine.
$27 - Homing pull-off, mm To play nice with the hard limits feature, where homing can share the same limit switches, the homing cycle will move off all of the limit switches by this pull-off travel after it completes. In other words, it helps to prevent accidental triggering of the hard limit after a homing cycle.
your debouce value might be too low, normally 250ms is default on other machines
now i am uncertain if there is a reason why its this low on the 3d printer. I am not very good on 3d printer firmwares.
the 3mm should be more than enough but you can start raising this 1st to 5mm
might be a trial and error
Edit, i am a better “visual/auditory” trouble shooter. if you could post a small video of the machine homing and failing (with sound) would help lots too!
I tried setting $26 to 250. No change, which makes sense since the switches aren’t actually getting triggered.
I tried setting $27 to 5mm. It didn’t change anything when homing from mid-bed, but when homing at home It almost seemed like it tried to “overstep” the home, causing clashing and a “trying to move but cannot move” noise.
I then tried setting $27 to 1mm, and it clicked much nicer when homing from home, but no change when homing from mid-bed.
Heres a video where i home from mid-bed, (Yes that very small step it does is the homing command being fired) and then home from home. This is before changing your proposed settings.
Silly theory
In fact the switches ARE seen as triggered i think
the little movement you are seeing IS the debouce
easy to test
Power on holding the switch one of them, and see if axis moves
Powering on while holding the X switch / pressing the X switch after powering on yields
ALARM:1
Hard limit triggered. Machine position is likely lost due to sudden and immediate halt. Re-homing is highly recommended.
[MSG:Reset to continue]
pressing home while holding the switch yields
ALARM:1
Hard limit triggered. Machine position is likely lost due to sudden and immediate halt. Re-homing is highly recommended.```
So the creality laser module actually takes over control of the motors. The original control board from the 3d printer has been removed completely. I am unsure if I can change the firmware of the laser module kit.
Homing did work just fine when it was a printer so I suspect a Config issue somewhere.
23 to 27 are all based on homing
I suspect could be something on the homing mask
But in fairness every time i went this deep in firmware i ended up getting it right by pure luck or trial and error
I am sure someone else in the forum will give you a hand!
This made me think. do you have a link of the product page?
so a double check on wiring coudl be done
Wondering if you are having power issues, as in not enough power onto the motors that would definitly be a problem
Many controllers care able to be powered by USB only, meaning you get connetion and all that but the 24v voltage remains dead.
I hadn’t thought about the voltage of the printer. My printers usually run 24V but this printer was a donation since it was faulty on the hotend side. I just checked and the Power supply for the printer (which is now disconnected since it’s powered by the laser module kit) was 12V. The laser module kit produces 24V. But i can jog the printer around just fine. It’s just the homing which is behaving oddly
Steppers motors are quite agnositc on voltage, the laser might not be though
if the controller is expecting 24v it might be anoyedf for not having them
I am thinking the kit came with a 24v power adapter correct. 24v 6amps output?
@gilaraujo Was on target here with his getting started link… The new board came in with default settings, unlikely correct for your machine. We need to go thru setting the parameters by the numbers. This means a lot of questions and answers, so please do not get discouraged.
Make sure the Jog controls are correct. Left-Right is easy +Right and -Left. If this is correct, then…
Yaxis travel ( the table in your case…) No wait! Is your machine like a Geeetech with a moving table, or is the table fixed and the gantry moves?
Apologies for the silence. Turns out new accounts are limited in the amount of replies they can make.
I tried giving the $22=0 command. The machine jog worked just fine for X and Y. There’s no Z on the controller.