@owend This is neat. I've never used global variables before but this might actually solve other problems too, thanks!
Best posts made by TechNi
Latest posts made by TechNi
Fix Z banding with input shaping?
Since input shaping is rather to compensate for vibrations at extreme speeds in X and Y direction, I wonder if it will be possible to introduce a Z-dependent compensation? Since lead screws are never 100% straight and thus shake the bed left and right if not properly kept in check with bearings, this would be neat.
The vibrations caused by uneven lead screws are very predictable and consistent, but they depend on the Z position. They usually increase the closer the bed gets to the motors.
Maybe somebody who has tested input shaping with Klipper or the RRF 3.4 beta can give some insight whether this is possible?
RE: Number of fans limited by firmware?
I can increase MaxFans in the next 3.4beta.
That would be cool! I guess there's a good reason for these limitations but I am sure the Duet can handle this.
@peter247 Neopixels are kinda expensive compared to "normal" LED strips and I'd like to be flexible.
@Phaedrux Did not know you could do that, thanks!
Number of fans limited by firmware?
With the new Duet 3, you can add basically infinite expansion boards. There's probably a limit somewhere but currently it seems like it's being dictated by the firmware and not the hardware?
I have LEDs on my printer which are seen by the firmware as "fans". I have the problem that I am running out of numbers. Apparently 16 fans are already too much as I am getting the following error:
M950: parameter 'F' too high
I can't define M950 F16 or F17 but I need two more fans. And I have plenty of free sockets thanks to the expansion boards. But the firmware seems to limit this. Is there any workaround or update coming to solve this matter?
RE: Duet 3 CAN connectivity issue
@dc42 Thanks a lot! The bootloader update actually solved the problem. Before the update, when I typed M122 B2 (or B1), it said "Bootloader ID: Not available". Now it shows the version of the bootloader (2.3 I think) and the LEDs blink in sync again.
Any idea what could have caused the bootloaders wipe on both EXP boards?
Duet 3 CAN connectivity issue
so I recently started to encounter a weird problem with my CAN connection. I have 1x Duet 3 MB6HC and 2x Duet 3 EXP3HC which are called Board 0, 1, 2 respectively. I read the CAN connection article and set the addresses accordingly (on off off off for board 1 and off on off off for board 2).
All boards run firmware 3.3 and I have run them for a few months already. I never had any issues with the CAN connection back then. Until I connected a 3rd expansion board during an overhaul (Note I also replaced the PSU and added some Noctua 4p fans in that same process).
The 3rd expansion board still had an older firmware installed and I also put the wrong address the first time when I powered it up (set it to 4 instead of 3). I am not sure if this is related, so treat this information with extra care.
Anyway, I disconnected the 3rd board and was back to the old setup (Mainboard + 2 exp boards). But the issue persists. So the following happens:
When I flip the power switch, the CAN LEDs of board 0 & 1 blink in sync. The CAN LED of board 2 (which is the termination board with the jumpers) does not blink at all. But all the other LEDs (Red, green, yellow...) of board 2 are lit.
Now board 0 & 1 blink in sync until board 0 has fully booted. Then they get out of sync and board 0 keeps rebooting every few seconds with the error messages shown below:
I have tried connecting board 0 and 2 only and this works fine (CAN LEDs blink in sync).
I have also tried connecting board 0 and 1 only and this works fine too. But once I connect both expansion boards, the issue arises.
Let me add one last bit of weirdness: Sometimes (like very rarely), all 3 boards work just fine and blink in sync like they did the last months before the overhaul.
(Note that I use the Duet 3 with an SBC (Raspberry Pi 4))
RE: Moving "beyond" the limit switch
I've set the center of the bed as origin (0,0), so my axes limits are defined like this in the config file:
M208 X200 Y200 Z200 U200 S0 ; set axis maxima M208 X-200 Y-200 Z0 U-200 S1 ; set axis minima
I think I've found the solution, though it's not very "clean" as I would prefer to have these kind of settings in my config and not my homing file:
; Homing X G91 M208 X200 Y200 Z200 U200 S0 ; set the original X axis maxima G1 H1 X999 F8000 ; Rough homing G1 X-10 F8000 ; Move back a few mm G1 H1 X999 F400 ; Precision homing M208 X205 Y200 Z200 U200 S0 ; set the extended X axis maxima G1 X5 F400; Move into final parking position
If I now calibrate the axis limits (e.g. for an IDEX printer), I have to change the limits in multiple homing files which is not very practical.
I wonder if there's a more practical solution?
Moving "beyond" the limit switch
I am homing my axes with a hall sensor which triggers about 10mm away from the sensor which is also the problem. I need the few extra mm and would like to park the print head a bit closer to the sensor.
I want to home the axis and then move ~5mm further than the defined axis limit and then define this as new axis limit. Is that possible?
What would I need to add/change?
G91 G1 H1 X999 F8000 ; Rough homing G1 X-10 F8000 ; Move back a few mm G1 H1 X999 F400 ; Precision homing G1 X5 ; Move into final parking position (beyond the limit switch)
RE: Issues with Haq XY/Markforged kinematics
Thanks for the help so far guys, appreciate it! I finally found time and I think I owe you an update.
I replaced the shaft with two independent motors connected to two drivers and installed another limit switch so that each end of the gantry now has one. This solved many problems including the mentioned twitch of the carriage when the gantry changed direction (or at least it reduced it to 0.01mm compared to 0.2mm before).
Now an issue which remains is that the carriage moves very slightly in the X direction when I want to move only the Y axis. I did some measurements with a dial gauge mounted to the gantry and this is the pattern I got (it's pretty consistent but not exactly linear):
(All units in [mm])
As you can see, the X axis also moves about 0.5mm when I move the Y axis 400mm. On some locations more than on others. Interesting thing is: it's almost exactly the same pattern & values for the second carriage.
Any idea what could cause this?