r/3Dprinting•
gdr

Filament knots breaking my print

Question

I have no idea where the knots are coming from. I've leveled the bed before printing. They're dropped all around the object and sometimes inside it, creating other problems including the layer shift on this photo.

https://imgur.com/2B9WlFM

I've cleaned up a bit mid-print, there were more. PLA+, Tevo Tornado, Two Trees magnetic bed. Any ideas what I can do?

Posted Nov 2, 2022, 11:58 AM UTC

59
Xionous_•

These are caused by over extrusion, to much pressure builds up in the nozzle then when the nozzle goes over an air gap or does a z hop a blob comes out.

7
gdrOP•

Woooah. That makes so much sense. Not sure what caused the overextrusion but I'll figure it out.

3
michaelcmetal•

I just printed that sd organizer. Handy little guy

1
gdrOP•

With some luck I'll find out myself in 5 hours 53 minutes.

2
muld3rkid•

Holy smokes that's long! what line width, infill, layer height are you using?

1
gdrOP•

0.15 layer height. The previous one was at 0.1 and took 10 hours. 10% infill. 0.4 line width.

It's going to be on my desk and I'm going to look at it all the time so I want it to look good. Normally it's 0.3 or 0.4 for functional prints.

The print failed btw, with lowered temperature and 97% flow, the same problem.

2
muld3rkid•

ahh i see. I started playing with line width (up to ~150%) and was able to reduce my average print times by 50%. IDK if that could help speed things up for ya.

WRT the knots, that's a wacky problem. How's your retraction settings? I've had something happen on a much much smaller scale and it was because I had filament oozing during the z-lift on new layer. This blob was getting dragged around, then getting deposited elsewhere in the print. might be part of your problem?

2