VEX custom plastic sheet question

I would like to discuss with teams.

We use plastic sheet to wrap around the robot sides, and this constantly getting hit by other robot in the match. So I like to use the most study material possible.

Which of the following legal plastic material is most durable ?

  • polycarbonate (Lexan),
  • acetal monopolymer (Delrin),
  • acetal copoly- mer (Acetron GP),
  • POM (acetal),
  • ABS, PEEK,
  • PET,
  • HDPE,
  • LDPE,
  • Nylon (all grades),
  • Polypropylene,
  • FEP.

I appreciate the discussion

From an engineering perspective, defining “sturdy” and “durable” are a bit qualitative. Here’s some engineering definitions to consider:

  • Strength: the ability to resist deformation…for metals and some types of plastics there is a point where the material begins to deform permanently (yield strength), and for all materials the point where it breaks (tensile strength)

  • Toughness: the ability to resist impact loading. Usually toughness inversely proportional to strength; that is, tough materials are not as strong, while strong materials start becoming brittle (the opposite of tough). This would be an apt comparison between polycarbonate and ABS

  • Stiffness/rigidity: engineers define this based on the Modulus of Elasticity. A material property surprisingly independent of strength and toughness. Higher modulus = higher stiffness

  • Fatigue strength: perhaps the most measurable factor for “durability”, it’s usually defined as the strength level where, under cyclic loading, a sample won’t break after 10^8 load cycles.

Short answer:
If we want to narrow the lists to what is easily available to teams, the ABS would be the choice for toughness (here’s our favorite source: 1/16" ABS Plastic Sheet 12" x 24" x 0.0625", 3 Pack, for VEX Robotics Plastic Sheets - It’s not as rigid as polycarbonate, but it’s pretty hard to break.

If you have a source (like MSC supply), then Acetal is the strongest/toughest of the whole list. Glass-filled grades of Acetal (or Nylon) would provide even more strength and rigidity.


i use nylon and its pretty good havent had a pice break yet its pretty flexible

McMaster-Carr has useful charts to compare plastics to each other.