Key takeaways
- PCTG and PETG are both glycol-modified copolyesters. They differ in proportion: PCTG carries more CHDM, and that is where its toughness and clarity come from.
- On the data sheets, PCTG's tensile strength (43–45 MPa) and HDT at 0.45 MPa (76 °C) are level with PETG. PCTG is not a higher-temperature plastic.
- The 92–94 kJ/m² impact and 215–220 % elongation are almost certainly moulded-specimen values — two brands publish near-identical numbers, and neither says the specimens were printed.
- PCTG wants a 90–110 °C bed, roughly 10–25 °C hotter than PETG. No hardened nozzle needed.
PCTG is turning up on more printer material lists — Creality's K3 lists it right beside PETG. It is usually introduced as “tougher PETG”. That is half right. This article reads two PCTG data sheets to separate the right half from the rest.
What PCTG is
PET, PETG and PCTG are one polyester family. PET uses ethylene glycol (EG). PETG replaces part of the EG with cyclohexanedimethanol (CHDM) so the plastic does not crystallise, which makes it printable and clear. PCTG pushes that ratio further: CHDM is most of the glycol. The result prints much like PETG but is tougher and clearer — extrudr stresses clarity, scratch resistance and chemical resistance.
Against PETG: two numbers match, two are worlds apart
| PCTG (extrudr) | PCTG (Fiberlogy) | PETG (Polymaker, printed) | |
|---|---|---|---|
| Tensile strength | 43 MPa yield · 45 MPa break | 43 MPa yield · 45 MPa break | 37.9–50.8 MPa |
| HDT 0.45 MPa | 76 °C | 76 °C | 76–78 °C |
| Elongation at break | 215 % | 220 % | 8.4 % (PolyLite) |
| Notched impact | 94 kJ/m² (Izod) | 92 kJ/m² (Izod) | 2.6–11.6 kJ/m² (Charpy) |
| Flexural modulus | 1,650 MPa | 1,600 MPa | — |
| Density | 1.23 g/cm³ | 1.23 g/cm³ | 1.24–1.25 g/cm³ |
PCTG's tensile strength and HDT sit right inside the PETG range. If your part fails from heat or from being pulled apart, PCTG solves nothing. The other two rows are an order of magnitude apart — and that is exactly where to slow down.
What can be said with confidence: PCTG's base polymer is tougher than PETG's, so a PCTG print will very likely take impact and bending better than a PETG print of the same shape. How much better on a printed part, these two data sheets cannot tell you.
Printing PCTG
Starting windows from the two makers
- Nozzle
- 230–270 °C (extrudr) · 250–270 °C (Fiberlogy)
- Bed
- 90–110 °C (extrudr) · 90 °C (Fiberlogy)
- Cooling fan
- 20–50 % (extrudr) · 0–25 % (Fiberlogy)
- Enclosure
- Not required; extrudr suggests one for larger parts
- Hardened nozzle
- Not required
- Max volumetric flow
- 9 mm³/s (extrudr, 0.4 mm nozzle)
- Drying
- 60 °C / 4 h (Fiberlogy)
The biggest practical difference from PETG is the bed: 90–110 °C against 70–85 °C. A printer topping out at 100 °C still works, with no headroom. extrudr's 9 mm³/s flow figure is low, too — PCTG is not a material for running a fast printer flat out. Like PETG, it grips smooth PEI very hard; use a textured plate or a release layer.
When to pick PCTG over PETG
- Clear parts — lamp shades, sight windows, display boxes. Clarity is the strength both makers lead with.
- Parts that get dropped, flexed or snapped together — where toughness matters more than stiffness.
- Not heat-loaded parts: HDT is level with PETG. A car in the sun still needs ASA or an engineering material.
- Not food-contact parts just because the resin carries FDA approval. extrudr notes certifications depend on colour; and a printed part is not the resin.
PCTG buys toughness and clarity. It does not buy a higher heat ceiling.
If you are choosing between PETG grades — regular, PETG 2.0, matte, PETG-CF — see PETG 2.0 and matte PETG. ZORVA's PETG data is on the PETG material page.
Frequently asked
Is PCTG stronger than PETG?
Tougher, yes; stronger, not really. PCTG's published tensile strength (43–45 MPa) and HDT (76 °C) sit inside the PETG range. The difference is impact toughness and elongation — but the very high numbers on PCTG data sheets are almost certainly from moulded specimens, not printed parts.
Does PCTG handle heat better than PETG?
No. extrudr and Fiberlogy both publish 76 °C HDT at 0.45 MPa for PCTG, level with the 76–78 °C Polymaker publishes for PETG.
What temperature do you print PCTG at?
extrudr gives a 230–270 °C nozzle and 90–110 °C bed; Fiberlogy gives 250–270 °C and a 90 °C bed. A bed 10–25 °C hotter than PETG is the main difference. Calibrate with a temperature tower on your own printer.
Does PCTG need an enclosure?
Not necessarily. extrudr only recommends one for larger parts; Fiberlogy says chamber heating is not required.