EDIT: I’ve followed [email protected] 's suggestions and I have rerouted the bowden tube. Tomorrow I’ll start another print and see the results. I’ll report back.

Here’s the whole printer during that print…

https://files.catbox.moe/smtxlj.webm

…and here’s a detail image:

The printer is a Creality CR5 Pro HT running Klipper - although I doubt this is too relevant. The extruder is of the “push type” with the hotend only including the heated nozzle. Current speed is 70mm/s in the layers but at the moment of the video 35mm/s due to the top layer.

I have no idea why, with a relatively symmetrical print just this corner is so messed up and underextruded. Any idea would be nice.

  • papalonian@lemmy.worldEnglish
    6·
    10 months ago

    Two guesses:

    Someone else pointed out that your Bowden tube looks a little pinched in some of the corners, I can’t tell which corner is underextruding from the video but possibly there’s filament slippage from that?

    Is there any oozing from the nozzle? If the corner with the problem is the “start” corner, any plastic that oozes out during travel isn’t making it into the print. Depending on your slicer you should be able to randomize the start location per layer to try to hide it, but if that’s the cause I’d try to figure out why it’s oozing so much.

    • the_third@feddit.deOPEnglish
      4·
      10 months ago

      Someone else pointed out that your Bowden tube looks a little pinched in some of the corners, I can’t tell which corner is underextruding from the video but possibly there’s filament slippage from that?

      Yep, it is exactly that corner where the radius of the tube reaches its minimum. I think that is a hot candidate for the main issue. Also after removing the print, it turned out the the outside had this issue as well and that was printed in the other direction. So, coming out of the slow corner the flow couldn’t accelerate quick enough to get back to volume due to high friction. Thanks, see my edit, I’ll report back!

      Is there any oozing from the nozzle?

      Yes, there is some. I have not calibrated retraction in Klipper yet, I know I should - however, this shouldn’t be the cause of this with almost no travel between layers or different parts in this model. But it’s on the list, you’re right.

      • papalonian@lemmy.worldEnglish
        1·
        10 months ago

        Yeah, if there’s not much travel distance between layers I’d say the Bowden tube is gonna be your culprit. Looks like if you just remove the tie connecting the tube to the cables going to the print head you’ll probably be fine, definitely report back!