PETG print parameters — temperature, bed, cooling and drying

PETG is the material for functional parts — the kind that have to survive a drop and a temperature higher than PLA will take. The manufacturer declares 85 °C of resistance and very good layer bonding, but in the same table it rates the stringing tendency as high, the top of the scale.

Porima has two PETG entries: plain and transparent. They differ in exactly three fields — cooling (100% versus 80–100%), surface finish and opacity. Every other parameter, temperatures and drying included, is identical. We cover the high-temperature version separately: HT PETG print parameters.

Full parameters for PETG and PETG Transparent

Parameter PETG PETG Transparent
Nozzle temperature 240–260 °C 240–260 °C
Bed temperature 60–80 °C 60–80 °C
Recommended nozzle diameter 0.4 mm 0.4 mm
Cooling (fan) 100% 80–100%
Drying 2–4 h at 30–40 °C 2–4 h at 30–40 °C
Enclosure (chamber) open frame, no enclosure open frame, no enclosure
Recommended printers all desktop-class FDM printers all desktop-class FDM printers
Bambu AMS compatibility Yes Yes
Print difficulty level easy easy
Print speed high high
Detail resolution 0.2 mm and above 0.2 mm and above
Abrasiveness (nozzle wear) none none
Warping tendency none none
Stringing tendency high high
Layer bonding very good very good
Support removal moderately difficult moderately difficult
Temperature resistance 85 °C 85 °C
Impact resistance high high
Flexibility high high
Moisture resistance low low
Surface finish glossy glossy, transparent
Opacity translucent transparent
Colour saturation high high
Odour very slight very slight
Post-processing moderately easy moderately easy
Chemical solubility very poorly soluble very poorly soluble
Spool material recycled plastic recycled plastic
Recycled content in filament no no
Recyclability yes yes
Diameter tolerance ±0.03 mm ±0.03 mm

Source: the official Porima FDM technical data table (FDM Technical Data). The descriptive ratings (none / low / medium / high) are the manufacturer's own labels, not the result of testing to any standard. Temperature resistance is the manufacturer's own declared figure — it is not HDT, nor any other normed test. The ±0.03 mm diameter tolerance comes from the manufacturer's data, not from the FDM table. See also the print temperature table and the filament drying guide.

How to print PETG

A nozzle temperature of 240–260 °C and stringing

The stringing tendency is marked as high, and that is this material's main problem. Start at 245 °C and print a temperature tower — every 5 °C downwards shows in the strings. Below 240 °C you start losing the layer bonding that the manufacturer rates as very good, so the bottom of the range is a real limit, not a suggestion. Retraction and travel speed do the rest: stringing — the full guide.

A 60–80 °C bed and the opposite problem to PLA

PETG sticks to the bed too well. On hot PEI it can tear a patch of the coating off along with the print, and on glass it can chip a fragment out of the sheet. Stay in the lower part of the range, 60–70 °C, and use a release agent: a thin layer of glue stick or hairspray. Glue plays the opposite role here to the usual one — it is there to weaken adhesion. Symptoms and what to do: the print will not come off the bed.

Cooling: 100% for PETG, 80–100% for the transparent version

This is the only parametric difference between the two entries. The manufacturer gives no reason, so we are not inventing one. At full cooling PETG holds its detail, but bridges and overhangs come out noticeably worse than with PLA — plan supports where you would not bother with them on PLA.

Drying: 2–4 h at 30–40 °C

PETG absorbs moisture quickly, and the manufacturer rates its moisture resistance as low. The result is crackling at the nozzle, bubbles and strings that no amount of retraction will remove. If a spool has been sitting open for more than a few days, dry it before you start tuning a profile — otherwise you will be calibrating the moisture, not the printer.

Supports and finish

The manufacturer rates support removal as moderately difficult — PETG fuses to the support more strongly than PLA does. Increase the support-to-model gap by one layer and print the support interface more slowly. Post-processing: moderately easy; chemical solubility: very poorly soluble, so there is no point trying acetone or limonene.

Enclosure and AMS

Open frame, all desktop-class FDM printers, warping tendency: none. Both PETG entries are marked as Bambu AMS compatible. Print speed: high.

The most common problems with PETG

  • Stringing — the manufacturer assigns PETG the highest degree of stringing tendency — this is problem number one for the material
  • The print will not come off the bed — PETG bonds to PEI and glass more strongly than it needs to; at the upper limit of 80 °C it can damage the bed surface
  • Blobs & zits — the same excess pressure in the nozzle that produces strings leaves lumps on the walls
  • Damp filament — low moisture resistance plus 2–4 h of drying in the manufacturer's FDM parameter table; PETG degrades in printing faster than PLA
  • Poor bridging — with full cooling and a tacky polymer, overhangs come out noticeably worse than with PLA
  • Poor surface above supports — support removal is rated moderately difficult — PETG fuses to the support more strongly than PLA

Filaments from this page: PETG Porima 1 kg and PETG Transparent. The whole category: PETG filaments.

PETG only needs tuning once, provided the filament is dry and consistent. Porima filaments are produced to a ±0.03 mm diameter tolerance, and we publish the manufacturer's full official print data — you don't have to guess it. Our warehouse is near Poznań, in Swarzędz.

PETG filaments · All print parameters · Filament drying · How to get rid of stringing