Polycarbonate in FDM printing: when the difficult material pays off
PC and PC FR bring heat resistance and toughness that PLA and PETG cannot reach. Where the materials shine, where they fail, and what they demand.
In the material list, polycarbonate is where things get serious: print temperatures beyond 280 degrees, a heated chamber as a prerequisite, and a material that punishes every process weakness. At the same time it delivers properties that are hard to find anywhere else on the filament shelf.
What sets PC apart from PETG and ABS
Three properties drive the decision. First, heat resistance: PC stays dimensionally stable up to roughly 110 to 120 degrees depending on load, PETG softens from 70, ABS around 95. Second, toughness: PC is impact resistant and tolerates repeated mechanical loading without turning brittle. Third, dimensional stability under heat: brackets and housings near motors or controllers keep their fit where other materials creep.
PC FR for electrical applications
The flame-retardant variant PC FR adds a UL94 V-0 rating at defined wall thicknesses. That makes it the standard for housings and carriers in control cabinets, battery holders and components at mains voltage, where a standard material drops out. Our article on flame retardancy in 3D printing explains the rating and its limits.
Why PC is considered difficult
PC absorbs moisture quickly and visibly: wet filament foams, creates bubbles and dulls the surface. It gets dried before every print and stored dry during it. Then there is shrinkage: without a heated chamber and proper adhesion, larger parts warp. Both are manageable, but they require a process set up for them, which is what makes PC more expensive to print than PETG.
- Typical applications: housings near drives, covers of hot units, battery holders, sight windows, test fixtures with temperature.
- Not suitable for: permanent contact with certain solvents, large thin faces without stiffening, parts in permanent water contact.
- Alternatives: PA12-CF when stiffness matters more than impact resistance; ASA when weathering rather than temperature is the issue.
When the premium is worth it
The rule of thumb is simple: if the part sees temperatures above 90 degrees continuously, must survive impacts, or a flammability rating is required, there is hardly a way around PC in FDM. Below that, PETG or ASA is the more economical choice, and we say so in the quote.
Send us your STEP file with the operating conditions. We will check whether PC or PC FR covers the requirement and quote you with a documented material batch.