Unstable filament drives and resulting groovemount damage

[helix_3]

i would suspect you are using the v3 hot end. the v3 is round all the way down to the nozzle and has the rubber insulation over it. the v3b has an aluminum block above the brass nozzle. given your era of printer, unless you have upgraded to a new hot end at some point you would be using the v3. 230 can be too hot. makergear ships your printer with a warning paper that says to not go over 220 deg. a short print to 230 may be ok but its borderline and over time your warping stuff.

Mine must be the v3b then, see here: http://i.imgur.com/j1IkuGg.jpg

Do the same limitations apply to the v3b? I thought these thermoresistors under-reported the temperature by 20C, making the max temp "250" c

[jimc]

ahhh yes you have the v3b then. yes the 20 deg difference applies. im not sure exactly whats going on then but im tellin you it really looks like a heat issue and you are runnin too hot. unless the ptfe liner in your insulator is really hot and reaching its glass point then a piece of filament driven by the extruder wont have enough force to drive it into the plastic like that. the ptfe might not be the hardest plastic in the world but its only a little stepper motor. it all looks very deformed as well. off the top of my head all i can think is a bad thermistor giving the wrong reading. have you messed with the firmware at all? changed setting or loaded new firmware at any time? if not then get a new peek insulator and print a new filament drive using abs and make it 90-100% infill. if it still does it then you got something else goin on.

[helix_3]

ahhh yes you have the v3b then. yes the 20 deg difference applies. im not sure exactly whats going on then but im tellin you it really looks like a heat issue and you are runnin too hot. unless the ptfe liner in your insulator is really hot and reaching its glass point then a piece of filament driven by the extruder wont have enough force to drive it into the plastic like that. the ptfe might not be the hardest plastic in the world but its only a little stepper motor. it all looks very deformed as well. off the top of my head all i can think is a bad thermistor giving the wrong reading. have you messed with the firmware at all? changed setting or loaded new firmware at any time? if not then get a new peek insulator and print a new filament drive using abs and make it 90-100% infill. if it still does it then you got something else goin on.

I haven't changed the firmware... ever, I don't think. I bought a backup thermistor, I guess I will swap it out and see if anything changes.

[jimc]

yes good. change the thermistor, the peek and print a good solid abs filament drive. after that you should be good to go. the makergear drives are printed with low infill. if you print it 100% then it should be rock solid. keep us posted on what happens

[Josh]

Helix, one thing that's definitely off with that hotend, is the gap between PEEK insulator and Aluminum heater block - it should be 2.5-3mm, not the <1mm shown in your picture. http://makergear.wikidot.com/m2-hotend-assembly has instructions for that - was that the one you replaced, or did you assemble that whole hotend yourself? That could be contributing to the overheating that Jim has suggested - I would think you'd see the entire barrel melt through the PEEK threads before deformation at the top, but it's possible.

[DIY3D]

Here's a picture of what PLA can do to PEEK: http://i.imgur.com/p5Uud68.jpg (this damage was my fault, because I didn't press the groovemount all the way in)

Yes, I recognize this. I felt that the filament was not aligned with that transit. There was a slightly difference in the the slot, between my old hotend end the new Once the hole caused the filament seems to clash and you can hear the clicking extruder. I solved it by making a small bevel with a slightly larger drill. That was the solution for me and till now it's printing without any problem.

Kind regards,
Marco

[helix_3]

Helix, one thing that's definitely off with that hotend, is the gap between PEEK insulator and Aluminum heater block - it should be 2.5-3mm, not the <1mm shown in your picture. http://makergear.wikidot.com/m2-hotend-assembly has instructions for that - was that the one you replaced, or did you assemble that whole hotend yourself? That could be contributing to the overheating that Jim has suggested - I would think you'd see the entire barrel melt through the PEEK threads before deformation at the top, but it's possible.

I assembled the hotend myself, and I never realized there was supposed to be a gap. I re-built it, and added some old insulation I had: http://i.imgur.com/UMcOkIP.jpg

[Dave K]

I've had a motor mount crack, which caused the motor and filament drive to rotate. Concluding that ABS was perhaps not tough enough for the job, I printed my motor mount and filament drive in PET+, which is supposed to be a bit stronger than ABS. Since I have only been using the PET+ parts for a few weeks, the jury is out on how long they will hold up.

I don't want to stray off topic, but I'm interested in how your PET+ holds up. I did the same, using PET+ clear filament, and I've done 7 hour prints at 255 without issues so far.

[Tim]

I had a good half-year or more of printing with the motor mount that was shipped with the M2 kit before it cracked, so it will take a good long while before I can say that the PET+ is doing as well as the ABS. If both of us have good reliability over a year, all the better. If we both scrap the existing mount because we get the dual extruder, then all that's out the window.

[Dave K]

I had a good half-year or more of printing with the motor mount that was shipped with the M2 kit before it cracked, so it will take a good long while before I can say that the PET+ is doing as well as the ABS. If both of us have good reliability over a year, all the better. If we both scrap the existing mount because we get the dual extruder, then all that's out the window.

Haha, good point. I'll be scrapping my results on the PET+ extruder motor mount as soon as I get the dual extruder in.