Metallic PLA Metallic-effect PLA (QIDI PLA Rapido Metal)

Metallic PLA is ordinary PLA colored to look like metal: silver, gold, bronze, copper and similar tones, with a soft metallic shimmer. The version we use, QIDI PLA Rapido Metal, is explicitly described by QIDI as containing no metal particles; the effect comes from the filament's finish and pigments. It prints like standard PLA, at the same temperatures and with the same fine detail.

This is different from true metal-filled filaments, which mix PLA with a large amount of real metal powder. The difference shows up immediately in weight. QIDI lists a density of 1.19–1.21 g/cm³ for PLA Rapido Metal, almost the same as plain PLA, while colorFabb lists 3.9 g/cm³ for its copperFill, which is PLA/PHA with fine copper powder. A metal-filled part feels cold and heavy in the hand, can be polished to a real metal shine, and is abrasive enough that Prusa warns it can wear a regular brass nozzle. We don't list metal-filled filaments.

Metallic PLA suits buyers who want a metal look at PLA prices: display models, product mock-ups, trophies, props, cosplay pieces, decorative hardware, signage and architectural models. It is a cosmetic material. Mechanically and thermally it behaves like PLA, which means it softens at low temperatures and is not meant for parts that work hard.

Mechanically, metallic PLA is a slightly weaker PLA. QIDI's product page lists 29–34 MPa tensile strength, 6–10% elongation at break and an elastic modulus of 3200–3500 MPa, so it is stiff but breaks rather than bends. In QIDI's comparison guide, PLA Metal shows a bending strength of 55 MPa, lower than its plain PLA Rapido.

The weakest direction is between layers. QIDI lists 17.5 MPa tensile strength in the Z direction for PLA Metal, roughly half the along-layer figure. This difference by direction is called anisotropy and applies to every FDM part. For a cosmetic part it rarely matters, but thin vertical features like sword blades or tall spikes should be oriented so they are not snapped off along a layer line.

Like all PLA, metallic PLA creeps under sustained load, meaning it slowly deforms if it holds weight or tension for a long time, and more so when warm. Use it for parts that are looked at and handled, not for parts that carry loads.

QIDI's comparison guide lists a heat deflection temperature (HDT) of 58 °C at 0.45 MPa for PLA Metal, and the product page gives a Vicat softening temperature of 62 °C. HDT is the temperature at which a test bar bends under a set load, and Vicat is when a needle sinks into the surface. In practical terms, this is a low-heat material that starts to soften well before boiling water.

QIDI lists optional annealing for PLA Metal at 60–70 °C for 2–4 hours, which can raise heat resistance somewhat. Annealing PLA causes shrinkage and can warp parts or change dimensions, and it may affect the metallic look, so we only do it by agreement and after a test piece. For most cosmetic uses we don't recommend it.

PLA has limited UV resistance, and the pigments that create a metallic look can fade or dull with prolonged sun. Indoor display under normal lighting is fine for years; a sunny windowsill can fade colors faster. A clear UV-resistant coat extends the life of the finish for parts near windows.

Metallic PLA has the chemical resistance of PLA, which is modest. Isopropyl alcohol for a light wipe is generally fine, but strong solvents, acetone and some cleaners can dull the metallic surface or soften it. Sunscreen and skin oils on frequently handled parts can slowly dull the sheen, which a clear coat helps prevent.

Keep metallic PLA away from fuels, solvents and hot soapy water. If it will be cleaned regularly, a mild soap and lukewarm water is the safe option, and testing on a hidden area is wise.

PLA absorbs only a little moisture, but damp filament prints with a rougher, less even surface, which is especially visible on metallic finishes. QIDI recommends drying at 50 °C for 4–6 hours and storing opened filament below 15% relative humidity with desiccant. We dry before cosmetic jobs.

Printed parts are stable in normal indoor humidity. Long-term exposure to heat and humidity together slowly degrades PLA, so keep display parts in a normal indoor environment.

Color choice matters more than with plain PLA. Silver and gunmetal tones hide layer lines best, while gold and copper show surface texture a little more. Fine features and lettering keep their metallic effect well, as long as the walls are thick enough to show color depth rather than looking translucent at the edges.

The finish is the reason to choose this material. QIDI describes PLA Rapido Metal as having a high-quality metallic sheen with no paint needed. Layer lines are still visible, but the metallic effect tends to make them look like a brushed texture rather than flaws.

Metallic effects depend on viewing angle and layer direction, so the same part can look different on top surfaces versus side walls. Tell us which faces are most visible and we will orient the part so they look their best.

Buffing and polishing: because there is no metal in QIDI PLA Rapido Metal, it can't be polished to a real metal shine the way metal-filled filaments can. Light buffing with a soft cloth can even out the sheen, and a clear gloss or satin coat can add depth. Aggressive sanding removes the metallic surface layer and exposes duller material underneath.

Painting and coating: a clear coat is the most common finish, protecting the sheen and adding UV resistance. The part can also be primed and painted with true metallic paints if a more realistic metal look is needed.

Metal-filled alternatives: true metal-filled filaments like copperFill can be sanded and polished to make real copper particles shine, as colorFabb describes. We don't list metal-filled filaments, because they are heavy, abrasive and costly. If you need that look, ask us about painting options.

Smoothing: vapor smoothing isn't something we offer for metallic PLA.

Metallic PLA prints with the same fine detail and dimensional accuracy as standard PLA. It shrinks little and rarely warps, so it is a good choice for detailed models and lettering.

Holes tend to print slightly undersized, as in any FDM material. For decorative parts that need to fit onto a base or another part, leave a little clearance, or order a test piece if the fit matters.