Flexible 3D Printing Filament Types: TPU, TPE & Soft PLA Guide

You’re probably here because rigid PLA just won’t cut it. Maybe your print needs to flex, bounce back, stretch, or just not snap in half under pressure. Whether it’s a phone case, a gasket, a soft robot joint, or some weird wearable idea, you’re now in the world of flexible 3D printing filaments.

But here’s the problem:
Flexible filaments like TPU, TPE, or soft PLA aren’t all the same. Some are rubbery and forgiving, others are more like bendy plastic. Some will glide through your printer like a dream, and others will jam, tangle, or print like mush if you're not dialed in.

This guide will save you the frustration.We’ll walk through exactly how to pick the right flexible filament, what to look for in your 3D printer setup, and how to avoid the usual mistakes people make when switching from rigid to flex.

Let’s get into it.

What Is Flexible 3D Printing?

Flexible 3D printing refers to the process of printing objects that are bendable, compressible, or stretchable using materials designed for elasticity. Unlike traditional PLA or ABS, which produce rigid parts, flexible filament for 3D printing allows you to create products that can twist, flex, or even rebound, just like rubber or silicone.

This is especially valuable in industries like medical prototyping, fashion, product design, and even robotics.

What Filament Is Flexible?

When we talk about flexible 3D printing filament types, we’re usually referring to:

TPU (Thermoplastic Polyurethane) – Most popular, great balance of strength and flexibility

TPE (Thermoplastic Elastomer) – Softer, stretchier, but slightly harder to print

Soft PLA – Modified PLA with rubber-like properties, good for those sticking to PLA-compatible printers

Each type has a different Shore hardness (a scale for measuring flexibility), so your end result can range from semi-rigid to ultra-flexible.

TPU is often the top choice when you need both flexibility and functional strength in a single print.

While flexible 3D printing filaments like TPU and TPE are popular for wearable and functional parts, not all projects require them. At JLC3DP, we currently specialize in high-precision resins and advanced engineering-grade materials, optimized for performance, durability, and fine detail. For clients needing flexible options, we're constantly expanding our material lineup. Reach out for a custom quote, we may already have a solution that fits

Pros of Flexible 3D Printing

A. Elasticity – Perfect for phone cases, seals, shoe soles, or wearables
B. Durability – Excellent impact and abrasion resistance
C. Vibration Dampening – Ideal for mounts, grips, and suspension components
D. Soft-Touch Finish – Adds comfort and grip to ergonomic designs

Whether you’re prototyping a custom wristband or printing a functional gasket, flexible 3D printer filament brings serious advantages to the table.

Challenges with Flexible Filament

Of course, flexible filaments aren’t plug-and-play. They come with their own quirks:

Feeding Issues: Flex filaments can jam in Bowden tube setups. Direct drive extruders work best.

Print Speed: Slow it down. Rushing results in stringing or inconsistent extrusion.

Retraction Settings: Dial these down to reduce blobs and oozing.

Bed Adhesion: Use glue stick, PEI sheet, or painter’s tape for better stick without damaging the print.

With some tweaks, even entry-level printers can handle flex filaments. But if your print setup isn’t dialed in, you’re gonna have a bad time.

Not sure if filament is the right choice? Our Resin vs Filament guide helps break it down.

Best Flexible Filament for 3D Printing

Here’s a quick rundown of popular flexible 3D printing filament choices:

If you're new, TPU is a great starting point. It’s forgiving enough for most setups and strong enough for real-world applications.

How to Choose the Right Flexible Filament

Not all flexible filaments are the same, and picking the wrong one can lead to failed prints, unusable parts, or printer jams. Here’s how to choose the right flexible filament for your project:

Shore Hardness: This tells you how soft or stiff the filament is. Lower Shore values (like 85A) are ultra-flexible, great for things like phone cases or gaskets. Higher values (like 95A or 98A) feel more like tough rubber and are easier to print.

Printer Compatibility: Not every printer can handle flexible filament well. Direct-drive extruders generally work better than Bowden setups, which may struggle with soft materials. Check if your printer supports TPU or TPE before buying.

Use Case: Match the filament to your end goal. Need abrasion resistance? Go with TPU. Want soft, squishy prints? Try TPE. Need to withstand outdoor conditions? Look for UV- or chemical-resistant variants.

When in doubt, go with a filament that's labeled beginner-friendly or tested on your printer model. Or better yet, let a professional service like JLC3DP handle the tricky stuff for you.

Use Cases for Flexible Filaments

Flexible filaments aren’t just cool, they’re functional. Here’s where they shine:

Wearables – Custom bands, straps, or fashion accessories

Seals & Gaskets – Airtight, watertight prints for appliances or vehicles

Footwear – Insoles, shoe uppers, or design prototypes

Tool Grips – Add comfort or anti-slip coating

RC & Drone Parts – Crash-resistant bumpers and protectors

If your part needs to stretch, squeeze, absorb shock, or stay silent (think vibration pads), flexible 3D printing is your go-to.

Printing Tips for Flexible Filament

To make flexible 3D printer filament behave, try these tips:

Slow Down: 20–40 mm/s max

Use a Direct Drive: Less distance = less chance of jamming

Minimize Retraction: Flex filaments hate aggressive pulls

Tune Temps: 220–250℃ for TPU, depending on brand

Keep It Warm: 40–60℃ bed helps with adhesion

Avoid Overcooling: Less fan = better layer bonding

Also: Store filament dry. Flexible filaments are notorious for absorbing moisture, which can cause bubbles or surface imperfections.

FAQ

Q: Can you mix flexible filament with PLA or other materials?

Technically, yes, but it’s not always pretty. Mixing TPU with PLA or PETG can lead to layer adhesion issues unless you’ve fine-tuned your temperature settings and slowed down the print speed. If you must mix, consider using multi-material printers or segmenting parts for mechanical joining. Bonus: We’ve covered surface bonding and dual-material tips in our 3D printing surface finish guide.

Q: What’s the softest 3D printing filament?

That title goes to TPU with a Shore hardness around 85A or lower. Some ultra-flexible brands go even softer. The lower the Shore value, the squishier your part.

Q: Can I use flexible filament with a Bowden tube printer?

You can try, but it's tough. Direct drive extruders are way better for flexible materials. Bowden setups often cause jams or unpredictable extrusion. If you’re stuck with Bowden, use a stiffer TPU (around 95A) and keep retraction minimal.

Q: Why does my flexible filament print look stringy or blobby?

This is usually caused by excessive retraction or printing too quickly. Flexible filament compresses under tension, so tweaking retraction and slowing things down helps. For a deeper fix, check our guide on how to reduce stringing in 3D prints.

Q: Is TPU waterproof or chemical-resistant?
TPU is water-resistant but not 100% waterproof under pressure. It also offers decent chemical resistance, like oils, greases, and some solvents. It’s popular for gaskets and phone cases for a reason.

Final Thoughts on Going Flexible

Flexible 3D printing isn’t just about making cool squishy toys, it’s about unlocking new functionality. Whether you need to absorb shock, wrap around a wrist, or grip without slipping, flexible 3D printer filament types like TPU and TPE can make it happen.

With a bit of patience and tuning, you can go from brittle plastic to bendy brilliance in no time.