Step 1: Preparation Before Printing

(1) Preparation of filaments

Choose TPU with the appropriate hardness. There are various hardness levels available for TPU in the industry, listed in descending order: 77D > 55D > 95A > 85A > 83A > 80A > 75A > 70A. Among them, TPU with a hardness of 77D and 55D is quite hard and can be printed using Bambu AMS and printers. TPUs with hardness levels of 95A, 85A, 83A, and 80A are moderately hard and can be printed using Bambu printers (higher hardness levels have lower risks of print failures). However, they should not be printed with Bambu AMS because they may bend inside the AMS, resulting in filament feeding failures. TPUs with hardness levels of 75A, 70A (or lower) should not be printed using Bambu printers as they are too soft and may get flattened by the extruder wheel, causing clogging.

Dry the filament. Use a forced air-type oven (recommended) or Bambu X1, X1C printers to dry the filament to prevent moisture-related issues such as excessive stringing or oozing in the printed models. The recommended drying parameters are provided in the table below:

 Forced Air Drying OvenBambulab X1/X1C Printer
FilamentTemperature / ℃Time / hBed Temperature / ℃Time / hTurning-over Time/ hCover
TPU65 – 75880 – 9012Every 6Filament box / PC Box

Kind notes:

(1) When using an oven to dry filament, it is recommended to use a forced air-type oven with sufficient capacity. Ensure that the filament spool is kept away from the heating zone as much as possible to ensure even temperature distribution and prevent deformation or damage to the spool and filament caused by localized overheating.

(2) When drying filament with the X1 or X1C printers, it is necessary to cover the filament spool with the original packaging box or a self-printed PC box. Throughout the drying process, make sure to tightly close the top cover and front door to maintain a higher temperature inside the space. Additionally, during the drying process, it is recommended to flip the spool to ensure thorough drying of the filament. For detailed instructions, please refer to:

Procedure and 3mf file for drying filament with the X1C heatbed | Bambu Lab Wiki

(3) For specific TPUs (77D and 55D) that can be printed with AMS, place the dried filament into the AMS and insert a fresh desiccant. Finally, lock the AMS to prevent the filament from absorbing moisture during the printing process.

For TPU filaments that cannot be printed with AMS, place the dried filament into a sealed box with a roller axle and insert a fresh desiccant. Then, lock the box to prevent the filament from absorbing moisture during printing. The roller axle helps reduce feeding resistance and prevent feeding abnormalities caused by excessive resistance.

(2) Choosing the printer and accessories

PrinterAMS & AMS liteNozzlePlateGlue
X1C, X1, P1S, P1P, A1 mini etc.Compatible: 77D, 55D, or higher hardness TPU Not compatible: 95A, 85A, 83A, 80A, or lower hardness TPU0.2 mm: Not recommended
0.4 mm: Recommended
0.6 mm, 0.8 mm: Not recommended
Compatible: Bambu Cool plate, PLA plate, Bambu engineering plate, high-temperature plate, textured PEI plateCompatible: Glue Stick, Liquid glue

Step 2: Parameter Settings

(1) Printing Parameter Settings

For Bambu TPU, it is recommended to use a 0.4 mm nozzle and the corresponding Bambu TPU preset. For third-party TPU, it is advised to use a 0.4 mm nozzle and select the Generic TPU preset with a lower maximum volumetric speed (print speed). If the third-party TPU has a hardness of 95A or higher and/or is specified as high-speed TPU, you may consider using the Bambu TPU preset and slightly increasing the “maximum volumetric speed” based on that. 

Please note that TPU is prone to feeding failures or clogging issues at higher print speeds. If you are unsure whether the TPU can be printed at high speeds, it is recommended to use a lower print speed whenever possible.

(2) Model Layout

TPU is prone to stringing. So it is important to avoid excessive travel. That is, you should avoid placing multiple models on a plate and printing by layer, but rather select a plate to place only one or a few models and print by object.

Not suggested:  print by layer
Suggested:  print by object

Step 3: Post-Processing after finishing the print

(1) Removing Models from the build plate

Generally, TPU exhibits strong adhesion to the build plate, making it challenging to remove large-bottomed models. In such cases, avoid using excessive force to prevent damage to the model or build plate. Instead, lift one corner of the model slightly to create a gap and spray alcohol into it. Then, you can carefully remove the model from the print bed.

(2) Dealing with Stringing on Models

Drying the TPU filament before printing will only reduce the amount of stringing on the prints, but will not eliminate it completely, especially on models with a lot of travel. To remove the stringing from the model, you can use hot air from a hairdryer to blow on it or use the flame from a lighter to quickly burn the stringing area. However, be cautious to avoid hurting yourself and damaging the model.

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