PETG

PETG is a go-to functional filament when you want more toughness and heat resistance than PLA, with a bit of flex instead of brittle snapping. It prints hot and “sticky,” so the two big success factors are (1) first-layer setup that avoids over-squish and bed damage, and (2) controlling ooze/stringing with the right temperature, retraction, travel behavior, and dry filament.

TL;DR

Print PETG a little hotter than PLA but with less first-layer squish; it can bond so hard to some beds that it chips glass or coating. If it’s stringing, dry the spool first, then lower nozzle temperature and tune retraction/travel.

PETGTopic-specific diagram for the concept, checks, and tradeoffs in this lesson.Dry spoolCompare tradeoffs before choosingSteady tempCompare tradeoffs before choosingCoolingCompare tradeoffs before choosingEasy finishCompare tradeoffs before choosing
A quick visual map of the main decisions behind PETG.

What you’ll notice while printing

PETG’s two signature behaviors are sticky and stringy. Sticky means the first layer can grab the bed aggressively and the nozzle can drag through the line if Z-offset is too low (over-squish), sometimes causing rough first layers or even damaging the build surface. Stringy means PETG tends to ooze during travel moves, leaving wisps and small blobs—especially when printed too hot or when the filament has absorbed moisture.

Typical PETG starting points (adjust per brand/printer)

Nozzle temperature
About 230–250 C. Lower tends to reduce stringing; higher tends to improve layer bonding.
Bed temperature
About 70–90 C. Many setups keep it warm for the whole print.
Part cooling fan
Lower than PLA. Too much fan can weaken layer bonding and make bridges brittle.
Print speed
Moderate. Slower often improves first-layer control and reduces nozzle drag on perimeters.

Stringing and blobs: fix in the right order

  1. Dry the filament first. Moist PETG often strings heavily and may pop/sizzle at the nozzle.
  2. Lower nozzle temperature in small steps (for example 5 C at a time) until stringing drops without losing layer bonding.
  3. Tune retraction for your setup: direct drive typically needs shorter retraction; Bowden often needs longer. Change one setting at a time.
  4. Increase travel speed if your motion system can do it cleanly; faster travels reduce the time ooze has to form strings.
  5. Avoid long idle time at printing temperature. Use standby temps or purge/prime routines before resuming moves if your workflow supports it.

PETG vs PLA: quick choice rules

  • Pick PETG for tougher parts, parts that may live in warm environments (like inside a car), or parts that see repeated impacts/handling.
  • Pick PLA for easiest printing, crisp edges/small details, and generally lower stringing.
  • If your part must be very rigid at thin sections, PLA can feel stiffer; PETG often needs thicker walls, ribs, or a different geometry to hit the same stiffness.