Plastic 3D Printing

Plastic 3D printing builds polymer parts layer-by-layer, enabling fast, low-volume, complex geometries with varied surface finishes and functional material options.

Overview

Plastic 3D printing creates parts by depositing, curing, or fusing polymer material layer-by-layer from a 3D model. Common technologies include FDM, SLA, SLS, MJF, DLP, and PolyJet, each balancing surface finish, accuracy, strength, and cost. It excels at complex geometries, internal channels, undercuts, and quick design changes without tooling.

Use plastic 3D printing for prototypes, functional test parts, fixtures, and low-volume end-use components where speed and design freedom matter more than tight tolerances or cosmetic perfection on every surface. Lead times are short and part cost is driven mostly by material volume, build time, and post-processing. Tradeoffs include anisotropic properties, limited long-term temperature and chemical resistance vs metals, and tighter tolerance features often needing secondary machining or inserts. For the right applications, it’s one of the fastest paths from CAD to physical parts.

Common Materials

  • ABS
  • PLA
  • Nylon 12
  • Nylon 11
  • PETG
  • Photopolymer resin

Tolerances

±0.005" to ±0.015"

Applications

  • Product design prototypes and visual models
  • Functional snap-fit housings and enclosures
  • Jigs, fixtures, and assembly aids
  • Ducts, manifolds, and complex internal channels
  • Medical and dental models
  • Low-volume custom consumer parts

When to Choose Plastic 3D Printing

Choose plastic 3D printing for fast-turn prototypes, fixtures, and low-volume parts with complex geometry where you want to iterate designs quickly and avoid tooling costs. It suits small to medium parts with moderate strength requirements, acceptable layer lines, and tolerances in the low-thousandths of an inch range, especially when the design may still change.

vs Metal 3D Printing

Choose plastic 3D printing instead of metal 3D printing when you prioritize cost, speed, and iteration over high temperature, extreme strength, or structural performance. It is ideal for form-fit-function checks, ergonomic models, and fixtures where polymers are sufficient and you want many design cycles without breaking the budget.

vs Composites 3D Printing

Choose plastic 3D printing over composites 3D printing when you don’t need the added stiffness and strength of fiber reinforcement and want lower material and machine time costs. It suits general-purpose prototypes, fixtures, and housings where isotropic high stiffness is not critical and simpler, cheaper materials are acceptable.

vs CNC machining

Choose plastic 3D printing instead of CNC machining when your part has complex internal features, undercuts, or organic shapes that are difficult or impossible to machine. It often wins for one-off to low-volume runs where you want to skip fixturing, toolpath programming, and waste from subtractive processes.

vs Injection molding

Choose plastic 3D printing over injection molding when volumes are low or the design is still changing and you want to avoid the cost and lead time of molds. It works well for pilot runs, bridge production, and validation builds where unit cost can be higher but no tooling is required.

vs Urethane casting

Choose plastic 3D printing instead of urethane casting when you need very fast parts, highly complex geometries, or frequent design changes that make reworking molds inefficient. It is more direct from CAD to part, with fewer steps and no pattern wear concerns, at the expense of more visible layer lines and limited material sets per process.

Design Considerations

  • Keep minimum wall thicknesses consistent and above the process limit (typically 0.8–1.5 mm) to avoid warping and fragile sections
  • Orient parts to minimize support on cosmetic or critical surfaces and to align layer direction with primary load paths
  • Avoid relying on as-printed threaded holes; use heat-set or press-in inserts or tap post-machined pilot holes
  • Call out only critical dimensions and tolerances; leave the rest "as printed" to reduce cost and inspection time
  • Add generous fillets at internal corners and transition areas to reduce stress concentrations and warping
  • Group small parts into a single build where possible, but maintain adequate spacing for powder removal or support access