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gr5

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gr5 last won the day on March 17

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  • 3D printer
    Ultimaker S5
    Ultimaker 3 (Ext)
    Ultimaker 2 (Ext
    +)
    Ultimaker Original (+)
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  1. So wait - you are using 1.75mm pla through smaller bowdens. Does the bowden go down inside of the print core? I guess that's fine. I can't think of any reason it would get hung up. How do you keep the smaller bowden from retracting into the feeder on retractions and chewing up the bowden in the feeder?
  2. Unlike some filaments, PLA tends to be able to last forever. It doesn't need to be kept dry. Although if you unspool "old" (even just 1 year old sometimes) PLA into the bowden and leave it in the bowden for 24 hours, many PLA formulations will crack. If retract the PLA back onto the spool before turning off the printer it's usually fine. "old" PLA does not like to be straightened out for more than a few hours. So that could be it. You can kind of tell because sometimes you can see the PLA has cracks in it when looking through the bowden. And when there is a retraction, sometimes you see where the crack is closest to the feeder which could be anywhere along the bowden. One fix is that if you leave filament in the bowden for more than 8 hours, take it out and cut off the last meter and throw that away. You can test the filament by bending it and it should not break. It should just bend in a knot. The longer you leave it unspooled, the more brittle the filament gets. Then the breaks in the filament reach the print head and sometimes they pass through but other times they get stuck in the printhead and your print fails. Once you get past the first meter (typically an hour or so) you are usually fine. I imagine 1.75mm filament isn't as bad because bending it is much less stressful for the plastic.
  3. oh! I totally misunderstood the graph. Okay so the orange graph is very flat. That's fine then. I was trying to figure out how the temperature was dipping. But it wasn't. It's the brown graph that is dipping - that's how much power is applied. For some reason it needs less power as you go. Probably extruding slower - or actually as you get farther from the glass bed, there is less bouncing up of the moving air around the nozzle so less nozzle cooling. That's probably it. Okay so there's nothing wrong with the temperature profiles. A red herring. Well... not much wrong. Something is loose I suppose and it measures infinite resistance and interprets that as 700 ohms, then kills power to nozzle, then temp retruns and it has to compensate for a bit for the lack of power but briefly enough that nozzle doesn't deviate from goal temp by much. So your print failure might have nothing to do with temperature.
  4. oh! Maybe it's not a problem then? But the whole thing is strange. There is a specific test that is in (I thought) all Ultimaker printers where if a printcore is getting 100% power for 30 seconds and the temp doesn't go up by 1C then it fails. I guess that means it is not getting 100% power. The PID values may need some adjustment. You could increase the P value. This is just strange. I've never heard of anyone adjusting their PID values for an ultimaker brand printcore. I'm still leaning to getting a new printcore. Did you check the cable in the printhead yet? I could help you program the printcore PID I suppose. I'm not a fan of that. Most printcores have zero values in the PID eeprom and uses default PID settings but I can show you how to program PID values into the printcore. First step is to put the printer into developer mode and then ssh into user/pass ultimaker/ultimaker If you can get that far I'll lookup how to program the PID.
  5. I don't like the way the temperature jumps to 700C briefly. Both in your latest graph and the earlier graph. Something is wrong there. There is a loose connection somewhere between the pt100 sensor and the bottom of your printer so it could be in the printcore (most likely), where the printcore connects to the print head, in the printhead connector, or where it connects to the PCB under the printer. It's common on the UM3 for the printhead cable to pull up and eventually out of the connector. On the top of the print head, remove the two very long (maybe 6cm) bolts. Nothing will fall apart. Then on the back half you can pop off the top cover - the back half of the top cover of the print head. Then you will see where the electric cable goes into the print head and to a connector. Push firmly down on the connector noting if it moved at all. Use a flat head screwdriver or similar so you can get a good look at it while you press down and see if it moves. If it does move, when you put it back together, put some paper or masking tape around the cable as a shim (google "shim wiki"). If the cable is fine then you should really throw away that printcore. It's very difficult to make those sensors reliable. You can't solder the pt100 to the wiring because solder melts 200C to 250C (depending on the type of solder). So instead the wiring is crimped to the pt100 and with lots of heating and cooling the crimp can fail. This is somewhat common (maybe 5% of all temp sensors fail within a year of printing - mostly a guess based on my printers). Do you still have all 3 of your original printcores? If not, it's time to buy one. Or you can use the BB 0.4 for PLA. It will work just fine. Consider using the BB as a test to see if this fixes your issue and if it does then we have definitely diagnosed the problem.
  6. Wow. Yeah that's extremely unusual. These nozzles should have plenty of power. This makes no sense. Why is extruder 2 heating up at all? Are you positive it isn't printing support or something with extruder 2? If a nozzle gets 100% power and still keeps cooling for more than 30 seconds, the printer will halt with an error code ("heater error"). Why isn't it halting with an error code? Maybe it's not getting 100% power? Why not? It just doesn't make sense. I'd try swapping with another core. Another AA 0.4. Your printer should have come with a BB 0.4 and two AA 0.4 cores. Also try going into the TUNE menu on the printer and go to the nozzle temp and it should show you what it thinks the temp is. YOu can adjust it upwards. You can also try slowing down the printer by 2X to see if the lower amount of flow results in less watage needed. You can also slow down the fans, sometimes the air from the fan gets diverted to the nozzle. Either bouncing off the heated bed or if there is no silicone sheild. Did you remove the silicone shield on the bottom of your print head? Maybe show a picture of that. They cost something like 3 for 5 dollars/euros.
  7. Maybe do the manual leveling before doing the xy calibration. I don't remember if that's mandatory but I think that's probably the problem.
  8. Are both nozzles hitting the glass at the same time? I guess not? That wouldn't make sense I think? So first the right nozzle hits the glass and then does the bed quickly drop down? Only after that it tests the left nozzle? Ideally both tests should stop right when the nozzle hits the bed. If it keeps pushing for like 3 more seconds then there is a problem. Having a sensor value of 2.3 is excellent. Anything below I think 8 is good. When the right nozzle is down it should be 1.5mm lower than the left nozzle +/- 0.7mm. You can see what that measured value is by looking in the logs. You can ssh to the printer if it's in "developer mode". Or you can just put a flash drive in there and in the menus you can dump the logs to a flash drive and examine them. Look at the date/time to find the most recent and search for these key words: "peak" and "Preliminary"
  9. Is the front fan working? The symptoms you describe sound like what happens when the front fan is not spinning. Not the side fans on the print head - the fan in the door of the print head.
  10. oh wow. Strange. Not sure if this is a hardware or software problem. Can you supply a wider angle photo that shows where it *was* printing on the bed? It looks like in the background it was near the left edge. Did it start doing this later in the print or right at the start? Part of me thinks it's a hardware problem where the steppers skipped some steps due to extreme friction or something. Part of me thinks the part was sliced on the far left edge (maybe the origin got messed up in cura which can happen). part of me thinks one of the gantry rods slipped out of the sliding blocks. I think we need more information. An overhead photo should help a lot.
  11. Oh, also in the start gcode you can put in variable like things. So you can put in something similar to M190 {material_bed_temp} or something vaguely like that and it will take the parameter you passed with -S and put it in there automatically. Using the CLI has a big learning curve.
  12. If you run cura normally there is a place to edit the start gcode - you go to PREPARE tab towards top (slightly left) on screen, then you choose your selected printer, then you choose "manage printers" then "machine settings", and then there is a tab where you can edit the start/stop gcodes. Slashee meant there I think. However, there is certainly another way to edit the machine profile file for your particular printer (anycubic mega...). I don't know where the file is stored but I do know it's complicated where you have machine profiles including/inheriting from other machine profiles and user overrides and all that. Usually, this is all taken care of for most printers but perhaps you chose the wrong anycubic mega model or perhaps anycubic never properly coded this up. slashee calls it a "printer definition file" so I guess that's what you need to edit if you do it by editing the file (versus editing it with the Cura GUI). There are 2 directory trees where things like this are stored. Both somewhat hidden. On linux it's in a hidden folder that starts with something like ".cura". On windows I think it can be in the installation folder possibly? Or the %appdata% folder somewhere. All I remember is that it is complicated with one folder holding installed printer definition files (and hundreds of other printers, hundreds of materials, profiles and more) and another completely separate directory tree holding files that users have/can edit to override the things in the first directory tree.
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