A seal that has to hug an uneven surface, a pad that damps an appliance's vibrations, a hinge handled ten times a day, a guide rubbing continuously against another part: some objects need something other than plain rigidity. For anything living indoors under no particular stress, PLA and PETG cover most needs, and we've given them a dedicated guide. But as soon as a part has to bend, absorb or last under friction, two other filaments enter the picture: TPU and nylon.
This guide helps you answer the real question when you're wondering which 3D filament to choose for a technical part: what does your part need in order to do its job over time?
When PLA and PETG are no longer enough
PLA is rigid and crisp, PETG more tolerant of heat and impacts. Both, though, remain rigid materials: under repeated flexing or permanent friction, they eventually mark, whiten or break. Two families of need justify moving up a level.
The first is flexibility: the part has to deform and then return to its shape. A seal, a protective pad, a cable grommet, a shell that absorbs drops. No setting will make a PLA flexible — that's a property of the material itself.
The second is mechanical endurance: the part moves, rubs, takes repeated cycles. A gear, a slide rail, a clip locked and unlocked hundreds of times. Here it isn't flexibility that counts, but the ability to last without wearing out.
TPU: the filament that bends without breaking
TPU (thermoplastic polyurethane) is an elastomer: a material from the rubber family, adapted to FDM printing, the fused filament deposition process. A TPU part twists, compresses, stretches, then returns to its original shape. It's the only material in our filament range that behaves this way.
What TPU does better than anything else
TPU excels wherever something has to absorb or conform: non-slip pads under an appliance or a piece of furniture, custom seals and cable grommets, corner protectors, handle end caps, mounts that damp the vibrations of a motor or a speaker. It's also an excellent choice for parts in contact with delicate surfaces: a TPU hook doesn't scratch what it holds.
Another advantage: the final softness of a part doesn't depend on the material alone. By playing with wall thickness and internal infill, the same reel of TPU can produce an object that's almost firm or distinctly squishy. That's a parameter we tune at the workshop according to the use you describe in your request.
The limits worth knowing
TPU isn't a structural material. Where it bends, it doesn't carry: a bracket or a load-bearing mount in TPU would sag. It's also more demanding to print than PLA, with reduced speed and specific settings, which lengthens machine time a little. Finally, very fine detail and sharp edges come out less crisply than on a rigid filament: you choose it for its function, not for engraving finesse.
Nylon: endurance for parts that work
Nylon (polyamide) is the material for mechanical parts that have to last. Rigid but not brittle, it tolerates flexing well without marking, and above all it slides: friction wears it far more slowly than other filaments. It's the historic material of gears and wear parts in industry, and that reputation holds up in 3D printing.
What nylon brings
Nylon comes into its own on moving parts or those under repeated stress: gears and pinions, slides and guides, heavily used hinges, clips that must survive hundreds of cycles, spare parts whose original broke because it was under-specified. On that last point, it's a valuable ally of our plastic part repair service: remaking a broken part in a material tougher than the original often settles the problem for good.
The flip side
Nylon is the most demanding of the four filaments in our range: sensitive to moisture before printing, it requires careful storage and drying and controlled printing conditions. It's workshop work, and that's reflected in its price. On appearance, its color range is narrower than PLA's: you choose it for its properties, adding a hand-painted finish if the part stays visible.
TPU or nylon: how to decide
If the part has to deform in order to work, it's TPU. If it has to stay rigid but absorb movement, friction or repeated cycles, it's nylon. And if it does neither, go back to PLA or PETG: there's no point paying for a technical material on a decorative part.
If in doubt, just describe the use: where the part lives, what it goes through, what it has to hold. That's exactly what we look at before suggesting a material in the quote.
What it costs
Our workshop's indicative rates put TPU from €35 per kilo of material and nylon at €65 per kilo, against €22 for PLA and €26 for PETG, with machine time at €7 an hour on top. A part is measured in tens or hundreds of grams, so the real gap on a small part stays modest, with an entry point around €15. The quote is free and sent within 24 hours, and production takes 3 to 5 working days depending on complexity and workshop load.
FAQ
Is TPU as flexible as rubber?
It comes close, with one nuance: the flexibility you feel depends as much on geometry (thickness, infill) as on the material. A thin TPU part will be very flexible; a solid one will stay firm. Specify the effect you're after in your request and we'll adapt the way the print is designed.
Can I order a single part in TPU or nylon?
Yes. Our on-demand printing service works with no minimum order, from a single part, with discounts on identical copies if you want several.
Which material to repair a broken original part?
It depends on the part's function: flexible, we go with TPU; rigid and under stress, with nylon or PETG. Send us a photo of the broken part and we'll identify the most suitable material along with the quote.
Your technical part, printed in Moselle
A custom seal, a replacement gear, a damping pad: send your STL, OBJ or 3MF file (or simply a link to a model) through our on-demand 3D printing page and get your free quote within 24 hours. For a broken part to remake, head to our plastic part repair service. And if your project stays in decorative or everyday territory, our guide to PLA, PETG and wood PLA will point you to the right material.