1
$\begingroup$

I have started printing with PETG so I can create objects that won't deform if I leave them in my car.

My first prints look good, but have strings of material coming off the print in places.

What should I try to prevent that?

I haven't had this problem with PLA.

$\endgroup$
3
  • 3
    $\begingroup$ Can you attach an image? $\endgroup$
    – Davo
    Aug 21, 2017 at 13:16
  • $\begingroup$ I know PETG by nature strings a bit. You may want to increase the temperature in the room, or add an enclosure. I think when the hot end pulls away from the piece, the material is instantly hardening causing the stringiness, maybe increasing the environmental temperature will allow the filament to release from the work piece before it hardens into a stringy mess. $\endgroup$
    – ctilley79
    Oct 15, 2017 at 21:28
  • $\begingroup$ Would turning off the fan that cools the filament (not the print head) accomplish the same goal of slowing down the hardening of the PETG? $\endgroup$
    – Gdalya
    Oct 16, 2017 at 23:55

2 Answers 2

3
$\begingroup$

I've had similar experiences switching from PLA to PETG, and haven't gotten it fully figured out yet.

From what I know so far, to reduce petg strings:

  • Increase retraction
  • Lower temperature
$\endgroup$
2
  • $\begingroup$ Thank you for your input. I spoke to a friend at work, and he said that he saw online somewhere that what you need to do is to adjust your temperature until you can just push through the filament by hand. He got good results printing at 250, whereas I was at 240 on a printer similar to mine. However, he also said that the exact temperature varies from printer to printer and also each spool of PETG may be different. $\endgroup$
    – Gdalya
    Sep 15, 2017 at 21:40
  • $\begingroup$ That sounds like good advice to me, thanks for sharing it! $\endgroup$
    – ctag
    Sep 16, 2017 at 1:12
2
$\begingroup$

If you are using a printer that runs Marlin, you might consider upgrading to a version with Linear Advance. Once I started using Linear Advance, I reduced the stringing of PETG. Also I was able to reduce the retraction amount without reducing the quality of the prints.

$\endgroup$
3
  • $\begingroup$ Thank you. How do I tell if my printer runs Marlin? $\endgroup$
    – Gdalya
    Oct 16, 2017 at 23:52
  • $\begingroup$ well , what printer do you have ? $\endgroup$
    – Kotiq
    Oct 17, 2017 at 0:13
  • $\begingroup$ Keep in mind that Linear Advance was added this year in the Marlin firmware . I also did a temperature tower print , and ended up lowering by 10 degrees the print temperature. You can start by doing that , before you start changing the firmware on the printer :) $\endgroup$
    – Kotiq
    Oct 17, 2017 at 0:15

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .