Antweight

The Antweight class is for robots weighing up to 1 lb (454 g) in the US. It's one of the most popular classes at local events, and includes the very popular Plastic Antweight class, where robots are 3D printed. Note: in the UK, Australia and New Zealand, "antweight" means a 150 g robot – see Fairyweight.

Rules

• SPARC: 1 lb (454 g), called Antweight in the SPARC Tournament Procedures. Shufflers can weigh 1.25 lb, non-traditional drives 1.5 lb, and walkers 2 lb.
• Plastic Antweight: custom parts must be 3D printed from specific plastics, under the SPARC Restricted Class Regulations (see Plastic Antweights). Some events use slightly different material lists.
• The UK has no 1 lb class, and NHRL doesn't run 1 lb robots (it holds separate antweight events).

Typical builds

• Drive: N20s or 16 mm brushed gearmotors such as the FingerTech Silver Spark or Repeat Mini Brushed, or small brushless gearmotors (see Insect Class Motors).
• Weapon: small brushless outrunner motors with a brushless ESC; belt drives are common.
• Battery: usually 2S or 3S LiPo, around 300–450 mAh.[1]
• Materials: aluminum, UHMW, polycarbonate, titanium and printed plastics for metal-class robots; printed PLA+, PETG and similar for plastic robots (see Armor and Materials).
• Common designs: wedges and control robots, lifters, vertical and horizontal spinners, drums and undercutters.
• Arena: SPARC recommends 1/4" polycarbonate walls and at least a 6 × 4 ft floor.

Getting started

• Kits (as of October 2026, many go in and out of stock): the classic FingerTech Viper (about $160 before radio and battery, with lifter and spinner add-ons); Palm Beach Bots plastic and metal kits (roughly $100–250); Repeat Robotics kits and parts; and the Turnabot SCAR plastic ant drive kit. See Kits.
• Plastic Antweights are often recommended for first-timers because they're cheap and damage is low.[2]
• Printable designs: many free 1 lb designs are listed on the 3D Printing page.

Where they fight

1 lb and Plastic Antweight are among the most common classes on RobotCombatEvents.com – plastic ant classes appear at most US local events, and some events are plastic-only. They're also popular at school and university events (see Combat Robotics in Schools and Universities).

See also

• Fairyweight (150 g) and Beetleweight (3 lb)
• Plastic Antweights
• Robot Classes