This is the strangest part for me - If LightBurn detects that your machine is a KT332N, it automatically redirects all commands for the Z axis to use the U axis instead, including the jog buttons - When you click the up/down arrows, if your Z axis is moving, that part is using our remapped jogging commands.
The “Get Positions” function is reading the U axis position and displaying that as the Z position, which could explain why yours is reading funny, but I’d honestly expect the Z axis values not to change at all, not read weird values.
It sounds like Monport had them make a version of either the controller or firmware that sends Z commands to the U axis, but only when running a file (maybe?) which breaks all our internal remap logic. Can you verify that for me? As in, you push the Up/Down arrow buttons and the Z axis moves, but Z commands in a running job don’t work?
One thing that’s worth asking - Are you trying to make the laser go IN to the material, or away from it? Where does the auto-focus trigger? At the top of travel, or at the material surface?
Based on what your machine is reporting for the Z coordinate, I’m worried that there may be more going on “under the hood” that just redirecting the commands from Z to U.
Hello Oz, thank you for digging into that topic.
I agree, that’s the weird thing. I can move the Z axis by using the up/down buttons in Lightburn. The table also moves by pushing the turn buttons for the U axis. But both type of buttons only work in jogging mode. As soon as I turn off the jogging mode and put in a defined distance (2mm for example), the table moves down but just keeps going and does not stop after 2mm… No matter if I push up or down, it only moves downwards.
Regarding your question to the autofocus: It triggers at the material surface. The nozzle and the tube of the laser head are spring loaded and the tube has ring with trigger rod on the backside of the laser head assembly. When I push autofocus, the table moves up and the nozzle gets in touch with the material and gets pushed upwards against a small limit switch on the backside of the laser head assembly. The controller gets the signal and moves the table back downwards until it reaches the focal distance. This can be set as pulloff distance or focal distance. Monport set it as pulloff distance but I changed it to focal distance. I think the function is the same and I tried both settings - it did not make any difference at all.
The “defined distance” thing makes sense, kind of, because of how jogging works in LightBurn. We read the current value, add your distance to that, then jog to that location. If it’s reading the current location incorrectly (for example, reading zero), it would be trying to jog to the wrong spot.
It sounds like they half implemented it, which is going to make it harder to support properly.
Regarding the auto-focus, once you’ve done that, Ruida controllers don’t allow the controller to move down (into the material) because that would be below zero, aka the safe Z height. If you are backing up to a focus height, and the controller is reporting a positive Z position, I’d expect it would still let you move down a bit from there, but it won’t let you go into negative numbers.
I agree, that makes sense somehow. But why are you doing that in absolute coordinates with the Z axis? In X and Y you are just using relative coordinates on the move panel , right?
You really think so? So why does RDWorks control it the right way as soon as I assign the Z axis to the pen control.
By the way, RDWorks assigns RD6445G to the controller. Maybe you should lean on the axis control for this type of ruida controllers?
I just tested if Z Offset IN (positive values) or Z Offset OUT (negative values) make a difference because I always tested OUT so far. But IN does not move the Z as well
Today I created a test file in RDWorks with the pen up/down function, saved it as .rd file and run it as an .rd file from Lightburn. The Z moves down and up as expected.
Here is the file: Z offset test_RDWorks-.rd (2,5 KB)
Okay, next test…
I disconnected Lightburn from the controller. As soon as I disconnect it, the ‘activate U axis’ switch shows up as ednisley discribed. I activated it. Then I created a .rd file with Lightburn with a negative Z offset of 3mm. Then I reconnected the controller and ran that .rd file directly from Lightburn again. It works as well! Here is the file: Lightburn disconnected from controller and U axis active.rd (1,6 KB)
So it might be sufficient if you prevent the ‘activate U axis’ button from behing hidden as soon as the controller comes online?!
For further testing I installed several software versions back to V1.0.00 and with that version it just works flawless! There is no option to activate a U-axis as well, but it just works.
Z Offset works, moving Z up and down to a specific travel distance works (it does NOT keep going as with the recent version). And I also prefer that Z moves first before X and Y - I know this was changed on purpose but as I am also having a CNC machine this sequence just makes perfect sense to me.
Hello Nicolas, unfortunately my ticket got closed without any solution for my issue (or even more an issue for several KT332NZ users like all people who own a Monport Onyx or the other Monport machines with that type of controller).
If simply unplugging the controller and enabling the setting works, then I should be able to add a setting to disable our internal override behavior. I find it bizarre that Monport decided to use a controller with the Z axis intentionally removed in a machine with a Z axis.
Does Lightburn detect the availability of a U-Axis from the connected controller? It seems like the ‘enable U-axis’ switch disappears once it’s connected, which might indicate that the U-axis was removed halfway in the firmware. This could also explain why the labeling for the up/down buttons on the control panel was changed from U to Z. Just guessing.
The presence of that option is just based on the hardware ID of the controller. I’ve added a switch to disable our internal axis remapping behavior and that will be included in the next release.
I set up my Monport Onyx yesterday and encountered the same problem with the Z-axis.
I was initially using version 2.0.4, and pressing the jog buttons in the software had no effect at all.
Then I came across version 2.0.5 with the “KT332N-Z remap” option. I had to disable the remap, and after that, I was able to move the Z-axis.
However, the joy was short-lived, as the Z-axis is behaving strangely. Sometimes it moves down, and sometimes up when I press the same jog button. Occasionally, the axis doesn’t move at all, and only after manually turning the leadscrew can I move it again.
When I use the “Z-Focus” function, the axis moves all the way up to the top limit and stops. It only moves again after I manually turn it down out of the limit switch.
I’m not very experienced with stepper motors, but could it be that it’s being driven incorrectly?
I agree, it sounds like someting with the speed and/or acceleration settings is not right. In this type of controller, both axis (Z and U) are available in the vendor settings. I would simply recommend setting both the same way.
Ed already mentioned the max. speed & acceleration settings… According to the description of the problem, I would also take a look on the setting for the jumpoff speed. Set this to 4mm/s.
And please also check the Home offset setting of each axis. If this is set to 0,000mm AND if the Focus Distance under the Miscellenous section is set to 0,0mm as well, the autofocus won’t work at all. It will engage the limit switch and stay where it’s at….
I really appreciate the support — it’s great to see how active and knowledgeable this community is.
Honestly, I wish I had found this forum before buying my machine… my choice probably would have been a different one.
I’ll test the suggested solutions as soon as I get some time and will report back with my results.
I changed the value for “Max Acceleration” from 5000 to 100. It seems to behave a bit better now, but the motor still sounds strange and sometimes stops completely.
I’m also not really sure about the meaning of the other settings like “Enable Homing,” “Limit Trigger,” “Invert Keypad Direction” (I don’t even have a keypad!), or “PWM Rising Edge Valid.”
Which of these should be copied from the Z-axis to the U-axis, or the other way around?
Should I really increase the Jump-off speed so that the motor starts moving more reliably from a standstill?
Here’s also a photo of the stepper motor that’s installed — maybe that helps. I couldn’t find any useful information about it online.
first of all, I don’t see any grease on that leadscrew. Maybe this a first action you can take and grease that stuff a little This stepper motor looks tiny, so I assume it does not have a lot of torque to overcome mechanical friction or minor misalignments.
With that stepper motor, I would keep the Jumpoff speed at 1 mm/s.
I’m just wondering how his Onyx (autofocus with fixed switch point, setting the focus height according to material height and a spreadsheet) is working good with Lightburn version 1.3.01: (369) Monport Onyx- Focusing #3 - YouTube
Which type do you have? I’m asking because this would give more clarity on the different settings of the Z and the U axis, especially regarding the home offset.
Assuming the Z axis settings control the motor, then Home offset = 0 means the head will not pull off the switch, the switch will remain active, and nothing will work. Set it for at least 7 mm to give that switch plenty of room to un-click.
At this point, it’s plausible to check for wiring & logic errors, because QC is not really a thing.
With the switch open (nothing touching that spring-loaded rod), check the state of the switch as the controller sees it using the KT332N display (Menu → Diagnoses).
If either Z+ or Z- is lit = red, then the switch is active when it should not be.
If both are dark, then pressing the switch lever should light the Z- indicator, not the Z+ indicator.
If pressing the switch does nothing, then there are real wiring problems.
@richi The thing with the grease makes sense — I tried that as well, but it didn’t improve the situation.
My Onyx is supposed to work like in the second video that was shared, or rather like in this Monport Onyx R Review.
Unfortunately, this laser doesn’t have a display — only a Start/Stop button and an emergency stop.
Is there any way to check those status values directly in LightBurn?
Right now, we’re assuming there’s probably a hardware defect, most likely caused by transport damage, since the laser was delivered upside down. I’ve been told I’ll receive a replacement unit within the next two weeks.
In the meantime, I’m allowed to play around with the current one, but I doubt I’ll get the Z-axis working properly.
Even with reduced acceleration, it still doesn’t move smoothly — sometimes it just rattles in place.
I checked the wiring as far as I could without completely disassembling the unit, but I didn’t find anything obvious. I can’t fully take it apart anyway since it has to go back.
Thanks a lot for all the great and friendly help here in the forum so far — really appreciate it!
This stepper motor looks tiny, so I assume it does not have a lot of torque to overcome mechanical friction or minor misalignments.