PCTG Filaments

3D print enthusiasts are always on the hunt for a good 3D printing material that best suits their printing purposes. Keeping that in mind, scientists are trying to sophisticate the pre-existing filaments while getting rid of the disadvantages people face when printing with them.

PCTG filaments are such an example. The industrial-grade 3D printing material is the better but lesser-known version of PETG filament.

What are PCTG filaments?

Polycyclohexane Dimethyl Terephthalate Glycol or in short PCTG, is an industry-grade 3D printing filament best known for its transparency, toughness, and durability. As mentioned, PCTG is the upgraded version of PETG filament. It has all the perks of PETG minus the drawbacks.

Compared to PETG, PCTG offers better chemical resistance, clarity, and impact resistance. This is why people prefer to use PCTG over PETG for producing demanding applications.

PCTG filaments are compatible with many open-source desktop printers. The filament provides remarkable dimensional stability, has a low percentage of shrinkage, and lasts longer than PETG.

PCTG properties

• Compared to the impact strength of PCTG filament is 20 times higher
• It has a much higher chemical resistance
• The optical transparency is also high unlike PETG
• PCTG is BPA (Bisphenol A) free.
• The filament comes with good mechanical strength and toughness.
• It exhibits a low rate of shrinkage and good dimensional stability

PCTG filaments are quite popular in the manufacturing industry because of their high ductility rate, higher chemical resistance, and low moisture absorption. The odour emitting rate is also low while printing. Their translucency has made them an apt option in the medical, packaging, and container manufacturing industries where esthetic appeal is crucial.

PCTG is an FDA-approved material making it a suitable option for packaging food. The filament is also widely used for producing kitchen utensils and similar objects that might come in touch with food.

How is PCTG made?

Polycyclohexane Dimethyl Terephthalate Glycol is created after performing a polymerisation method. PCTG filaments include three raw materials (dimethyl terephthalate, cyclohexane dimethanol, and Glycol). The inclusion of Glycol acts as a reactor that binds the monomers, cyclohexane dimethanol, and dimethyl terephthalate, for starting the polymer chain.

After polymerisation, a thermoplastic substance is created with properties like strength, translucency, and chemical resistance. The created polymer needs to be processed so it can be turned into filament. What will be the material’s ultimate properties It highly depends on the conditions of polymerisation and the control of monomers adding to its popularity and versatility.

PCTG filaments are used in making medical devices, food containers, water bottles, robotics, and electronic devices. The filament is very popular in the food packaging industry because of its food safety features. Since it checks all the strict regulations regarding contact with consumables, the filament can easily get FDA approval.

Moreover, PCTG has a non-toxic chemical composition. Due to its high chemical resistance, harmful materials don’t get leaked and contaminate food or drinks. PCTG filaments can withstand extreme heat making them the right material to use in producing reusable bottles and other utensils.

PCTG vs. PETG – What are the differences?

So, which is better PETG or PCTG filaments?

Both filaments have some excellent features unique to their chemical composition although they share similar properties. But which one will be the best choice? The answer entirely depends on your printing requirements.

For instance, if you want to print outdoor applications that are strong and durable and wouldn’t deform being out in the sun, PETG may be the best choice. The filament is easy to print with. They are primarily used in producing prototypes, functional parts, and containers.

On the contrary, if certain applications demand higher impact resistance, more flexibility, rugged usage, and better transparency, then the right choice of filament will be PCTG.

They are highly used in making transparent casings, medical apparatus, and applications meant for robust usage.

Printing with PCTG filaments

In terms of printers, PCTG filament is compatible with nearly all FDM or FFF 3D printers. Just make sure they have a heated bed and the print temperature can go up about 240-260°C. PCTG-compatible printers require the heated bed to reach around 70-80°C for proper bed adhesion.

Three of the best PCTG-compatible 3D printer brands include

1. Creality
2. Prusa
3. Ultimaker
4. Bambulab

1. Temperature settings

Depending on the PCTG filament’s brand, the print temperature can vary. So, always check the manufacturer’s instructions. But, normally, the ideal temperature for the filament ranges somewhere between 240-260°C.

The heated bed temperature needs to be around 70-80°C for the best output. Excessive print temperature can result in warping or stringing whereas a low print temperature means blobs, bad layers, and bed adhesion. Adequate hotend temperature ensures smooth filament extrusion, prevents nozzle clogging, and perfect layer adhesion.

Do small experiments with the filament to find the right print temperature. For temperature adjustment, it’s wise to make small decrements or increments of 5°C till you find the suitable temperature.

Pro tip: Always use adhesive aids and a heated bed to print with PCTG. Recalibrate the printer and attune the print speed and temperatures to get the expected results.

2. Bed adhesion

Ensuring proper bed adhesion is crucial if you don’t want the print to come off while printing. It gives a solid foundation to the print when the filament sticks to the surface perfectly. Using a heated bed at 70-80°C is the first step in achieving proper bed adhesion.

Also, print beds such as PEI or BuildTak sheets or glass plates are suitable for improving bed adhesion. The filament often fails to adhere when the build plate hasn’t been cleaned. So, clean the surface thoroughly with isopropyl alcohol before printing.

Apply PVA-based adhesives, glue sticks, or hairspray for reinforcing adhesion. Enable the auto levelling feature if available or level the bed correctly to get a smooth first layer.

3. Print speed

The right printing speed is around 30-50mm/s for PCTG. Anything higher can compromise the accuracy and details of the design. If the model design is simple, you can increase the speed to print faster. For intricate shapes and designs, it is best to print at a lower speed.

You can adjust the speed by making small increments to find the correct speed. Make sure you are aware of the printer’s capability. Consider the layer height before setting the speed as larger layers need to print faster compared to smaller layers.

Advanced tips and troubleshooting

Like every other filament PCTG also has some common issues that need troubleshooting for achieving high-quality 3D prints. The issues are:

1. Lifting and warping

The reason behind this issue is poor bed adhesion. When the filament doesn’t attach to the surface it tends to come off or get warped in the process. To avert this issue, keep the temperature of the heated bed at 70-80°C, use bed adhesives, and keep the build surface clean.

2. Stringing

Since PCTG needs to print at a high temperature, stringing can be a serious problem. Calibrating the retraction settings can help avoid this issue. Also, lower the travel distance and increase the travel speed to decrease oozing.

3. Bad layer adhesion

Fast cooling or inadequate hotend temperature may cause this issue. So, lower the cooling percentage and increase the temperature to avoid prevent this problem.

4. Overheating

If the temperature is too high it can cause print deformation, blobs, or oozing. To ward off this issue, keep the temperature within the suggested amplitude.

5. Bridging issue

Attune the bridging settings. Readjust the print orientation, cooling speed, and print speed. Check overhang angles and use adequate support structures.

Calibrate your printer frequently and maintain a steady print environment. Use the best quality PCTG filament for printing. Read the manufacturer’s recommendations for optimal results.

Frequently asked questions

What is PCTG material?

It is a copolyester filament best known for its mechanical strength, impact resistance, transparency, and durability.

Is PETG better than PCTG?

The filaments share some common features but which one is best depends on your printing requirement. PETG is more popular than PCTG because of its stability in terms of flexibility and strength but if your print needs enhanced strength and clarity opt for PCTG.

Is it safe to print on PCTG?

Yes, though you should follow the safety instructions of the filament manufacturers.

Is PCTG recyclable?

Yes, but the recycling infrastructure of PCTG is not as well established as PETG.