SainSmart 87A TPU Filament 1.75mm Flexible 1kg Spool - Durable TPU

In this review of the SainSmart 87A TPU filament, the bottom line is straightforward: this spool is for makers who need a flexible, impact-resistant material for practical parts rather than glossy showpieces. It prints as a soft but durable TPU with an 87A hardness and 1.75mm diameter, and the single biggest reason to buy is its balance of flexibility and structural strength, which suits functional prints like tire inserts, bumpers, or seals. The filament is formulated to be flexible yet retain a rigid internal structure that stands up to repeated stress.

Key Features

• Flexible formulation: The material has increased flexibility while keeping a rigid structure, so printed parts absorb impacts without collapsing.
• Consistent diameter: The 1.75mm diameter offers predictable feeding and layer consistency when your printer is set up correctly.
• Medium hardness: At 87A shore hardness, the filament delivers a useful balance between softness and wear resistance for functional parts.
• Direct-extruder suitability: Designed for direct-extruder setups with close feed roller contact to avoid curling and feeding issues common to flexible filaments.
• Good environmental resistance: The TPU shows solid performance for waterproofing, cold and UV resistance, making it suitable for outdoor or industrial-use parts.
• Premium mechanical properties: TPU's high mechanical strength and slight transparency mean prints can be both strong and visually useful for prototyping.

Who It's For

This filament is aimed at hobbyists, makers, and small workshops producing functional items that need to flex and recover: tire inserts, seals, protective covers, and impact-prone prototypes. Users who prefer a spool that handles repeated bending and exposure to outdoor conditions will appreciate the 87A hardness and TPU durability.

It is less suitable for beginners who only have Bowden-style setups or printers with a wide gap between feed roller and extruder, since flexible filament can curl and jam if the filament path is not tight. If your priority is glossy visual models or ultra-rigid parts, a PLA or PETG filament would be a better fit.

Pros & Cons

Pros

• Good balance of flexibility and structural strength for functional, impact-resistant parts.
• Designed for direct extruders, reducing common feeding problems when set up correctly.
• Resistant to water, cold, and UV, expanding real-world use cases beyond indoor prints.
• Reasonable consistency in print quality when customers report good results, especially for tire inserts.

Cons

• Flexible nature requires a proper direct-extruder path; printers with gaps or Bowden tubes may experience feeding issues.
• Customer reports on filament quality, adhesion, and softness are mixed, so results can vary by machine and settings.

Specifications

Material	TPU (Thermoplastic Polyurethane)
Diameter	1.75mm
Spool weight	1kg
Hardness	87A
Density	1.12 g/cm3
Recommended extruder	Direct extruder with no feed gap

Our Verdict

The SainSmart 87A TPU filament is a solid choice for users who need flexible yet tough parts and can print with a direct-extruder setup. It delivers good impact resistance and environmental durability for practical prints, offering strong value when used on compatible printers and with tuned settings.

Frequently Asked Questions

Will this filament work in a Bowden setup?
It is designed for direct extruders; Bowden setups or printers with gaps between the roller and extruder may experience curling and feeding problems.

What kinds of parts is this filament best for?
Use it for impact-prone and flexible parts like tire inserts, seals, protective covers, and prototypes that need to flex without breaking.

How does it handle outdoor exposure?
The filament reports good waterproof, cold and UV resistance, making it acceptable for outdoor or industrial use when printed correctly.