NameThatPart

Knowing the name of things is part of the challenge of building things; it's difficult to do internet searches if you don't know the name of the thing you're looking for, even harder if you don't know it even exists. This page contains some things useful for building robots that you might not know the name of, so you can get a start.

Materials

Plastics

• Polycarbonate: This material that is typically optically transparent which makes it ideal in situations where you need to see into your robot.
• PLA: Polylactic acid is a thermoplastic often used in 3D printing. It is moderately strong but it's ease of use makes it a popular choice.
• ABS: Acrylonitrile butadiene styrene is also a common plastic used in 3D printing. It is stronger than PLA but can be more difficult to work with.
• Nylon: This plastic is often used in 3D printings and its flexibility allows it to make very durable parts but more preparation is needed to use it successfully.
• Delrin / Acetal: This low friction high durability plastic can be used instead of aluminum in some cases. Its much lighter but not as strong.
• HDPE / UHMW: These high strength plastics are often used as armor. They tend to deform and bend instead of cracking or completely failing.

Metals

• Aluminum:
  • 6061:
  • 7075:
• Titanium:
• Steel:
  • Mild Steel: Low Carbon steel which is typically lower in cost and easier to work with.
  • Tool Steel: High Carbon alloys that can be very strong and resistant to deformation and abrasion.

Composites

• FR4 / G10: This material goes by several names including GRP (Glass reinforced polymer), FRP (fiber reinforced plastic), G-10[1], and Garolite. It's made of resin reinforced by glass fibers. G10 is available in sheets, rods, corner angles, etc.[2] According to ULS, this material can be laser cut with a CO₂ laser.[3] FR4 is also flame retardant, and is a common material for circuit boards.[4][5]
  • G10 has very high strength compared to unreinforced plastics, and is resistant to abrasion and cracking. In combat robotics it can be used as lightweight armor[6] or structural members in insect weight classes. It's an insulator, and won't short out electronics even if opponents attack and shred it.
  • Safety: Use appropriate protective gear to avoid inhaling glass fibers when cutting or handling this material.

Fasteners

List of common types and what they do

• Nuts, bolts screws
  • Wood screws, and self tapping screws - create their own thread in softer materials, which gets weaker each time it's used.
  • Machine screws/ bolts - screw into a threaded hole, either in a nut, threaded insert, or material which has been tapped (had a thread cut)
  • Shoulder bolt - A bolt which has a "shoulder" - smooth machined section which can be used as a shaft.
  • Locking nut / Nyloc nut - a nut containing some plastic / rubber material which makes it self-tighten and resist e.g. vibrations.
  • Threaded inserts aka "Insert nuts" - an internally threaded part which can be pushed or screwed into a softer material to allow a machine screw / bolt to be attached strongly and repeatedly. Some types

• Rivets and other one-time fasteners
  • Pop-rivets - a fastener which can connect thin(ish) materials with access from one side only. Difficult to remove (must be drilled out usually)
  • Rivnuts / rivet nuts - a combination of a rivet and a threaded insert, i.e. a rivet with a thread inside so a machine screw can be screwed in - very handy.

Other hardware

• Threaded rod - just a rod which is threaded along the full length so you can put many nuts on in different positions to e.g. hold parallel parts
• Nut strips - a strip of (typically) metal with periodic threaded holes, perhaps at right-angles, to attach parts at right angles