Thermoplastic
PLA (polylactic acid)
The default printing polymer. Accurate, easy, and not for service parts. We print it; we do not injection mould it.
Published values for unfilled grades at 23 °C unless stated. Confirm against the supplier datasheet for the grade you specify.
What it is
PLA is derived from plant starch and is the easiest polymer to print. It has low thermal expansion, so it does not warp on an unheated bed, and it prints crisp detail with good dimensional accuracy.
It softens at 55–60 °C, which rules it out for anything that sees sun, an enclosure with electronics in it, or a car. It is a geometry and fit material, not a functional one.
Where it is used
- Form and fit prototypes
- Concept models and design reviews
- Jigs and fixtures for bench use
- Casting patterns
- Low-load display components
Processing notes
Prints at 190–220 °C nozzle, 50–60 °C bed. No enclosure required.
Layer adhesion is good, so Z-direction strength is a smaller penalty than with ABS.
Annealing at 90–100 °C raises heat resistance significantly but causes 1–3 % shrinkage that must be compensated.
Available through
Can PLA be injection molded?
Yes. Resin suppliers sell injection grades of PLA, and the polymer runs on a standard moulding press. We do not offer it, for the same reason we limit it to printing: a heat deflection of about 55 °C means a moulded PLA part softens in a parked car, in sunlight or beside a warm circuit board, so very few production parts can use it.
PLA is also moisture sensitive and has to be dried before moulding. If the reason for choosing it is a bio based or compostable claim, confirm that claim with the resin supplier for the exact grade, because it depends on the grade and the end of life route, not on the polymer name.
For a moulded part, quote it in a resin we run: ABS for a rigid housing, PETG for a clear and tough part, or polypropylene for a low cost, chemically resistant one. Injection molding vs 3D printing sets out when printing stops making sense.
PLA grade families
| Grade family | Made for | At Trumould |
|---|---|---|
| Filament grades: standard, PLA+ or tough, filled, high temperature | FDM printing | Printed, see 3D printing |
| Injection grades | Moulding thin or detailed parts | Not offered |
| Sheet and film grades | Extrusion and thermoforming | Not offered |
Supplier grade codes differ by manufacturer. The modulus on this page is the flexural modulus of an unfilled grade; for tensile or shear modulus, and for melt flow, use the datasheet of the exact grade.
Design notes
Treat printed PLA as a visual and dimensional check, not a mechanical test.
Orient the part so load runs across layers, not along the layer boundary.
If the prototype must be tested mechanically, print in PA12, PETG, or ABS instead.
Grades and variants
- Standard PLA, general purpose
- PLA+ / tough PLA, impact modified
- Carbon or wood filled, cosmetic and stiffness variants
- High-temperature PLA for annealing
- Water-soluble PVA as a support pair
Specifying this material?
Send your CAD and target volumes. We come back with a price, a lead time, and any material or design notes that would reduce either.