TPU & Flexible 3D Printing: Grips, Gaskets & More

Most 3D printing materials are rigid by design. TPU is the exception, and that one difference opens a whole category of parts that no rigid plastic can make. If you need something that bends, stretches, grips, seals, or absorbs a shock, you need a flexible material. TPU is the one we reach for, and here is how it works.

What TPU Is

TPU (thermoplastic polyurethane) is a flexible, rubber-like filament. Instead of snapping, it stretches and springs back. It is also surprisingly tough, with good abrasion resistance and the ability to absorb impacts without cracking. Think of it as the difference between a hard plastic clip and a rubber band: same idea, completely different behavior.

Flexibility Comes in Grades

Not all flexible filament is equally soft. Flexibility is measured by shore hardness, and the grade you choose changes everything about how the part behaves. A harder TPU prints more easily and feels semi-rigid, while a softer TPU feels more like rubber but is trickier to print. Matching the right grade to the job is a big part of getting a flexible part right.

What TPU Is Great For

• Grips, handles, and soft-touch covers
• Gaskets, seals, and weather strips
• Bumpers, feet, and vibration dampers
• Protective cases and phone covers
• Flexible hinges and snap fits
• Wear pads and anti-slip surfaces

Anywhere a part needs to give a little, cushion a load, seal a gap, or improve grip, flexible material is the answer. We see a lot of replacement gaskets and custom grips, because these are exactly the small rubber parts that are hard to source and easy to design.

TPU Properties at a Glance

Printing Flexible Material Is Its Own Skill

Flexible filament does not behave like rigid plastic in the printer. Because it bends, it is harder to push through the machine cleanly, so it prints slower and needs careful tuning of speed, flow, and feed. Rush it and you get jams or blobs. Done right, you get a clean, consistent flexible part that performs exactly as intended.

Design matters too. Very sharp corners and ultra-fine detail are harder to capture in a soft material than in rigid PLA. We often adjust a design slightly, rounding tight features or thickening thin sections, so the flexible version performs the way the customer actually needs it to.

Choosing the Right Softness

When a customer asks for a flexible part, our first questions are about feel and function:

• Should it be barely flexible and structural, or genuinely rubbery?
• Does it need to seal under pressure, or just cushion a bump?
• Will it stretch repeatedly, or flex only occasionally?
• Does it contact oils, chemicals, or just air and hands?

Those answers point us to the right grade and wall design. A vibration-damping foot wants a different setup than a stretchy strap or a compression gasket, even though all three are flexible parts.

Common Flexible Jobs We Print

We regularly print custom gaskets and seals to replace cracked originals, soft grips and overmolds for tools and handles, protective bumpers and corner guards, and anti-slip feet for equipment. Because these are often one-off or small-batch parts that you simply cannot buy off the shelf, custom 3D printing is frequently the most practical way to get them at all.

The Bottom Line

TPU and other flexible materials fill the gap that rigid plastics cannot: parts that bend, grip, seal, and cushion. The trade is a more demanding print and slightly softer detail, both of which we manage by tuning the machine and adjusting the design for how the part will actually be used.

Got a gasket to replace or a grip to improve? Send us the part or a sketch of what it needs to do. Upload your STL and we will dial in the right flexible material and hardness for the job.