PETG HF, PETG-CF, PCTG and PETG Translucent: the Differences

Highlighted terms are explained briefly when you hover over or tap them.

Three of these are variations of PETG. PCTG is a plastic in its own right that, according to manufacturers, is similarly easy to print. The difference in brief:

• PETG HF is PETG that flows better for faster printing. For this, Bambu Lab gives slightly lower nozzle temperatures than for normal PETG.
• PETG-CF contains carbon fibres. It is stiffer, matt and needs a hardened nozzle.
• PETG Translucent is designed for light transmission. How clear the part becomes depends heavily on the settings.
• PCTG is a PETG alternative with, according to the manufacturer’s datasheet, much higher impact strength, but it prints hotter.

How normal PETG is printed is explained in Printing PETG.

Overview based on manufacturer figures

The values for the PETG variants come from the Bambu Lab wiki, the PCTG values from Fiberlogy’s datasheet. Other manufacturers sometimes give different ranges, and the figure on your spool always takes priority.

Bambu Lab gives the nozzle temperatures with a tolerance of plus or minus 10 °C. For comparison: for normal PETG, Prusa recommends 230 °C for the first layer and 240 °C for the following layers, with the bed at 85 °C and then 90 °C.

PETG HF: what is different?

HF stands for High Flow, meaning a high flow rate. It refers to a PETG formulation that flows more easily in the nozzle, so that the printer can feed more material per second and therefore print faster. ELEGOO gives print speeds of up to 600 mm/s for its PETG HF, but recommends moderate speeds for the most consistent quality. Siraya Tech describes its high-speed PETG as a formulation for a flow rate of up to 25 mm³/s.

PETG or PETG HF?

• Same uses: Both are suitable for robust everyday and functional parts.
• Temperature: According to Bambu Lab, PETG HF prints in the range 230 to 260 °C, normal PETG in the range 240 to 270 °C.
• Speed: The advantage of PETG HF only shows if the printer actually uses the higher speed. On a slow printer it brings little.
• Moisture: For damp PETG HF, Bambu Lab has a dedicated profile, “Generic PETG HF”, with 220 °C and 16 mm³/s. This is slower than the standard profile “Bambu PETG HF”. After drying, Bambu Lab recommends the standard profile again.

Bambu Lab makes no statements in its wiki about differences in strength between PETG and PETG HF.

PETG-CF: with carbon fibres

Short carbon fibres make the material stiffer and give a matt surface. In return, it is abrasive:

• Hardened nozzle: Bambu Lab specifies a hardened nozzle for PETG-CF. According to Bambu Lab, brass and stainless steel wear quickly. The first choice, it says, is a 0.6 mm nozzle made of hardened steel, and for the special Bambu filaments such as PETG-CF a 0.4 mm nozzle made of hardened steel. A 0.2 mm nozzle is not suitable because of the risk of clogging.
• Multicolour system: Bambu PETG-CF is approved in the AMS, not recommended in the AMS lite.
• Gloves: Bambu Lab advises wearing protective gloves when working with carbon fibre filament, because fine fibre dust can irritate skin, especially at broken edges.

More on fibres, nozzles and wear can be found in Fibre-reinforced filaments.

PETG Translucent: as see-through as possible

According to Bambu Lab, PETG is fundamentally clearer than PLA because it is amorphous, whereas PLA is semi-crystalline. For the highest possible transparency, Bambu Lab recommends:

1. Dry it well, otherwise bubbles form.
2. Large nozzle, 0.8 mm recommended, so that fewer lines and transitions appear.
3. No top and bottom layers, infill 100 % and rectilinear, so that all the lines run in the same direction.
4. Higher temperature and slightly more flow rate, so that the lines flow into each other without gaps. Only with dry filament.
5. Fan off and print slowly, Bambu Lab gives 20 mm/s.
6. Sanding afterwards improves light transmission further.

Even with these settings, the result depends heavily on the shape. According to Bambu Lab, complicated models hardly become properly transparent, and simple shapes work best.

PCTG: tougher than PETG

Fiberlogy describes PCTG as an alternative to PETG with higher impact strength and heat resistance. The values from Fiberlogy’s datasheet:

For comparison, Fiberlogy gives 5 to 8 kJ/m² for PETG in the same test. This is the comparison value of a single manufacturer. How much PCTG and PETG from other brands differ is only shown by their own datasheets.

PCTG is printed slightly hotter than PETG, according to Fiberlogy at 250 to 270 °C on a bed at 90 °C, with 0 to 25 % part cooling. According to the manufacturer, an enclosed printer is not necessary.

Drying

All the variants absorb moisture. For PETG, PETG HF, PETG-CF and PETG Translucent, Bambu Lab gives the same values: 60 to 65 °C for 8 hours in a convection oven or 65 °C for 8 hours in the AMS HT or AMS 2 Pro. For PETG HF and PETG Translucent, ELEGOO recommends 60 °C for 8 hours. More on this in Drying and storing filament.

Which variant for what?

You can find more materials compared in the filament overview.

Sources

• Nozzle and bed temperatures, nozzle and AMS compatibility of all PETG variants: Bambu Lab Wiki: Filament guide and material table
• Compatibility, drying, carbon fibre note, transparency: Bambu Lab Wiki: PETG
• Damp PETG HF, Generic PETG HF profile: Bambu Lab Wiki: PETG HF unfinished drying
• Transparent prints, amorphous and semi-crystalline: Bambu Lab Wiki: Transparent PETG
• PETG temperatures at Prusa: Prusa Knowledge Base: PETG
• PETG HF at up to 600 mm/s, drying: ELEGOO: PETG HF
• Drying PETG Translucent: ELEGOO: PETG Translucent
• High-flow formulation up to 25 mm³/s: Siraya Tech: High Speed PETG Filament
• PCTG datasheet and comparison with PETG: Fiberlogy: PCTG Filament