Skip to content
Mechanical, Build & Pneumatics·Lesson 14 of 47

Polycarbonate and Other Materials

Polycarbonate is the tough, cheap, easy-to-cut plastic that handles impacts aluminum can't.

Sign in to track progress, earn XP, and save lessons.

Polycarbonate (Lexan)

Polycarbonate, often called by the brand name Lexan, is a clear, extremely impact-resistant plastic. In FRC it is used for:

  • Intake plates and guards that take repeated hits from game pieces.
  • Bellypans and panels that protect electronics.
  • Flexible or compliant parts where a little give is desirable (it bends instead of shattering).

It is easy to cut on a bandsaw or router, drills cleanly, and can even be scored and snapped for straight cuts. Crucially, it is forgiving of impacts that would crack acrylic or dent aluminum. A common rookie mistake is using acrylic (Plexiglas) instead — acrylic is brittle and shatters; choose polycarbonate for anything that takes a hit.

Cutting and bending tips

  • Drill polycarbonate with sharp bits and moderate speed; it can crack if you force a dull bit.
  • It can be cold-bent in a brake or line-bent with a strip heater for clean folds.
  • Leave the protective film on while machining to avoid scratches.

Other common materials

  • 3D-printed plastics (PLA, PETG, ABS, nylon, TPU) — fast for prototyping and for non-structural or lightly loaded parts (spacers, brackets, intake rollers). Nylon and reinforced (e.g., carbon-fill) filaments are stronger; TPU is flexible for compliant wheels/rollers.
  • Delrin / acetal — a slippery, machinable plastic good for low-friction sliding surfaces and custom gears.
  • UHMW — ultra-high-molecular-weight polyethylene, an extremely slick plastic for wear strips and low-friction guides.
  • Wood / plywood — invaluable for prototyping mechanisms quickly before committing to metal.
  • Rubber/polyurethane tread and compliant wheels — for grip in intakes and on drivetrains.

Choosing a material

Match the material to the load and the failure mode:

  • High structural load → aluminum.
  • Impact and abuse, needs to flex not break → polycarbonate.
  • Fast iteration or complex shape, low load → 3D print or wood.
  • Low-friction sliding → Delrin/UHMW.

Keeping a small stock of polycarbonate sheet, a few filament types, and scrap plywood lets a team build and revise mechanisms quickly.

Key takeaways

  • Polycarbonate (Lexan) is impact-resistant and easy to cut/bend; use it for intakes, guards, and panels
  • Avoid acrylic/Plexiglas for impact parts — it is brittle and shatters
  • Use 3D printing and wood for fast prototyping, and Delrin/UHMW for low-friction sliding surfaces

Go deeper

Lesson quiz

Required

Answer all 3 questions correctly to complete this lesson.

1.Why is polycarbonate (Lexan) preferred over acrylic (Plexiglas) for FRC parts exposed to impacts?

2.What is true about cold-bending (brake-forming) polycarbonate sheet for robot parts?

3.Under the current FRC rules, what does the rulebook require for bumper backing material?

Answer every question to submit.