Random overextrusion after 3+hours of printing FW 3.5.2
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@charliedrums Looking at this logically, any print move looks like this. G1 Xnn Ynn Enn. Which means move a certain distance in X and/or Y while extruding a certain amount of filament. What you are saying is that at random times, when printing a gcode that you have printed many times before, that Enn becomes something greater. I.e, the fimant moving through the extruder randomly moves further or faster than it should do. There are many reasons why it might move less (partial blockage, temperature too low, motor or wring issue, missed steps, etc), but none that I can think of that would make the filament move further than it should. So the only logical conclusion is that something else is happening which gives the appearance of over extrusion when in fact it isn't. My best guess, as I've stated before, is that your Z axis isn't moving the full layer height.
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I would have guessed the same but I have checked all 4 Z motors and their harnesses. Here is what leads me to determine it is over extrusion. First once the issue begins, I remove the print from under the extruder and let it print in air for a while and visibly one can tell the more amount of plastic is being forces through the nozzle.
Second, I am using the Orthus Filament Monitor. The orthus has a light that flashes intermittently when filament is running through it. The faster the blink of the light the faster the filament if passing through the sensor, when the problem begins the light flashes faster as in filament is passing faster trough the sensor/extruder. I can move the printer to the max height(365mm) and home without any problems.
I’m going one thing at a time right now I eliminated the z scanning probe and the filament sensor. Still happening. This time around I re did the harness that powers the tool distribution board (two cables 24v Vin ground) and am currently running the print to see if the problem continues after this, I’ll re do the RJ11 cable. Then continue from there.
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@charliedrums If you are certain that it is genuine over extrusion after some seemingly random period of time, then the only explanation I can think of is that somehow, something is changing the G1 Xnn Ynn Enn commands that exist in the gcode file to something like G1 Xnn Ynn E(some other value that is always higher). I note that you are using a SBC. Is there any chance that you could run stand alone mode and print directly form an SD card?
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@charliedrums One other suggestion - try a print without input shaping. I can't offhand think why it should make a difference but who knows?
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@deckingman
Yes, I can I don’t see why not. The only reason I have SBC is so I could get WIFI. Looking through the documentation I see that I can connect to the board directly with an ethernet cable. Next thing Ill do is that go Direct an eliminate the SBC and see. Thanks for the idea. -
@charliedrums said in Random overextrusion after 3+hours of printing FW 3.5.2:
@OwenD I have printed the gcode before. Probably like 30 t50 times and it has always worked. Still gave it a look but found nothing out of the ordinary.
Good that you're keeping an open mind.
Having printed the code before may not prove anything.
For example in my case the Gcode extrusion values were far above the capabilities of the extruder, but I wasn't getting skipped steps because my maximum extruder speed values were limiting it to achievable amounts (albeit way over extruded).
If in the interim you had for example increased your max extruder speeds then a problem that wasn't obvious before may now appear.
Loading the code into Prusa Slicer and viewing it by volumetric flow rate would show up any odd areas most likely a lot more than just scanning the code by eye.Have you tried swapping the drivers around that the extruder is on?
That should rule out a hardware fault on the board at least.EDIT: Just saw that you're using a tool board and have swapped it.
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Just noticed a similar post also using a toolboard
https://forum.duet3d.com/topic/35869/overextrusion-out-of-nowhere
One for @DC42 I think -
@charliedrums One other thing to try, I think you said that once it gets into this "over extrusion mode" then it stays in it even when starting a new print? If that is the case can you try checking the extruder calibration when in this state see: https://docs.duet3d.com/en/How_to_guides/Calibration#h-3-calibrating-extruder-e-steps-per-mm and then do a reboot and perform the same task again and see if there is any difference.
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undefined Phaedrux moved this topic from General Discussion
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After many weeks of testing, I figured out the problem. I started re-wiring every cable to eliminate any problem with the harnesses. Once I got to the power from the Mainboard 6HC to the tool distribution board. I measured the power from this cable with a multimeter and everything was reading normal. For some reason once I rewired this harness everything seems to be working now.
I’ve done dozens of 20–50-hour prints with no problem so far. Updating this post in case someone is having the same issue. Check the power from the main board to the tool distribution board.
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undefined chrishamm has marked this topic as solved
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@charliedrums I'm glad you solved it! Thanks for the update.
