Published on Fri Feb 24 2023 14:27:35 GMT+0000 (Coordinated Universal Time) by Alex

PolyMaker PolyFlex TPU95: Your Guide to Flexible 3D Printing

PolyFlex TPU95 from PolyMaker is a well-regarded thermoplastic polyurethane (TPU) filament designed for 3D printing flexible and elastic parts. This article provides a comprehensive overview of PolyFlex TPU95, covering its specifications, best practices for successful printing, and a critical evaluation of its performance.

What is PolyFlex TPU95?

PolyFlex TPU95 is a filament known for its balance of flexibility and ease of printing. The “95” in its name refers to its Shore hardness (95A), indicating its relative softness and elasticity. This material sits in a sweet spot, making it suitable for a range of applications from phone cases and wearables to gaskets and custom grips.

PolyFlex TPU95 Specifications

Here’s a detailed breakdown of PolyFlex TPU95’s key specifications:

• Material: Thermoplastic Polyurethane (TPU)
• Shore Hardness: 95A
• Diameter: Typically available in 1.75mm and 2.85mm
• Diameter Tolerance: ±0.02 mm
• Printing Temperature: 220-240°C (depending on your printer and environment)
• Bed Temperature: 25-60°C (heated bed recommended, but not always necessary)
• Printing Speed: 20-50 mm/s (slower speeds generally recommended)
• Density: 1.19 g/cm³
• Recommended Bed Surface: Blue tape, PEI, glass with glue stick.
• Cooling Fan: Recommended (at low speed)
• Storage: Store in a dry environment with desiccant.

Successfully Printing with PolyFlex TPU95: Tips and Tricks

Printing with flexible filaments like PolyFlex TPU95 requires a bit more finesse than printing with rigid materials like PLA or ABS. Here are some key tips to achieve optimal results:

• Printer Setup is Key:

  • Direct Drive Extruder: A direct drive extruder (where the extruder motor is mounted directly above the hot end) is highly recommended. Bowden extruders (where the extruder motor is separated from the hot end by a PTFE tube) can be problematic with flexible filaments due to their tendency to buckle or stretch within the tube. If you must use a Bowden setup, keep the tube as short as possible and reduce retraction.
  • Nozzle Type: A standard brass nozzle will work fine. However, if you plan to print with TPU frequently, a hardened steel nozzle can offer improved wear resistance.
  • Extruder Idler Tension: Adjust the idler tension on your extruder so that it grips the filament firmly but doesn’t crush or deform it. Too much tension can lead to clogs, while too little can cause slippage.

• Fine-Tuning Printing Parameters:

  • Printing Speed: Slow and steady wins the race. Flexible filaments tend to stretch and compress under pressure, so printing slowly minimizes these issues. A good starting point is 20-30 mm/s.
  • Temperature: While the recommended range is 220-240°C, finding the sweet spot for your specific printer is crucial. Start at the lower end and increase the temperature in increments of 5°C if you encounter under-extrusion or poor layer adhesion.
  • Retraction: Minimize retraction as much as possible, as excessive retraction can lead to clogging. Start with a retraction distance of 1-2 mm and a retraction speed of 25-40 mm/s and adjust from there. Sometimes disabling retraction completely yields the best result.
  • Layer Height: A layer height of 0.2 mm is a good starting point, but you may need to adjust it depending on the complexity of your model.
  • Infill: Experiment with different infill patterns and densities to achieve the desired flexibility and strength. Gyroid or concentric infill patterns often work well with flexible filaments.

• Bed Adhesion Strategies:

  • Heated Bed: A heated bed is highly recommended, typically between 25-60°C.
  • Bed Surface: Blue painter’s tape, PEI, or glass with a glue stick can all provide good adhesion. Ensure the bed is clean and level.
  • First Layer Height: Ensure your first layer is slightly squished onto the bed to maximize adhesion.
  • Brim or Raft: Adding a brim or raft can improve adhesion, especially for parts with small surface areas.

• Preventing Stringing:

  • Temperature: Lowering the printing temperature can help reduce stringing.
  • Retraction: As mentioned above, minimizing retraction is key.
  • Travel Speed: Increasing the travel speed can also help reduce stringing.
  • Dry Filament: Dry filament is crucial (see below)

• Moisture is the Enemy: TPU is highly hygroscopic, meaning it readily absorbs moisture from the air. Moisture can cause a variety of printing problems, including stringing, bubbling, and poor layer adhesion.

  • Storage: Store your PolyFlex TPU95 in an airtight container with desiccant when not in use.
  • Drying: If you suspect your filament has absorbed moisture, dry it using a filament dryer or an oven set to a low temperature (around 50°C) for several hours.

PolyFlex TPU95: A Critical Evaluation

Let’s evaluate PolyFlex TPU95 based on several key criteria:

• Print Quality (7/10): PolyFlex TPU95 can produce prints with good detail, but achieving optimal surface finish can be challenging, especially with complex geometries. Stringing and bridging can be problematic if settings aren’t dialed in.
• Toughness (8/10): PolyFlex TPU95 exhibits good tensile strength and tear resistance, making it suitable for applications that require durability.
• Flexibility (9/10): Excellent flexibility and elasticity. Bends and compresses easily, returning to its original shape.
• Warping (9/10): Minimal warping, even on larger parts. Bed adhesion is generally good, reducing the risk of warping.
• Adhesion (8/10): Good layer adhesion, resulting in strong and durable prints. However, optimal bed adhesion requires proper bed preparation and temperature settings.
• Moisture Sensitivity (4/10): Highly sensitive to moisture. Requires careful storage and drying to prevent printing problems.
• Color Range (7/10): Available in a decent range of colors, including transparent options. However, the color selection may not be as extensive as with some other filaments.
• Temperature Range (8/10): Suitable for a moderate temperature range, making it compatible with a wide range of 3D printers.
• Odor & Fumes (9/10): Low odor and fumes during printing, making it a good choice for indoor environments.
• Spool Winding Quality (8/10): Typically well-wound spools, minimizing the risk of tangling or breakage during printing.

Overall Average Score: 7.5/10

PolyFlex TPU95 is a solid choice for users looking to print flexible parts with good durability and elasticity. However, its moisture sensitivity and the need for precise printing settings require some experience and attention to detail. Despite these challenges, the material’s versatility and low odor make it a valuable addition to any 3D printing arsenal.

Written by Alex