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Our neckerchief is green and black

Pinewood Derby
Racing home made gravity powered toy cars!

We race model cars powered by gravity alone we made ourselves with Mums' and Dads' help against each other to see whose is fastest. This is a huge annual thing in the States but is just beginning here in the UK.

The kit

Each entrant starts from the same kit which comprises a block of balsa (originally this was pine), four wheels and something for axles. There is a small charge for this kit of parts of £3. Alternative kits are available on eBay and from blockcars but are typically a bit more expensive. Help from parents, siblings etc is positively encouraged. Entrants may add and subtract from this kit with their own materials, provided they keep within the Rules.

The Rules

There are some simple rules to keep everyone's car safe and within reason:

  1. Size: Cars have maximum dimensions of 17.5cm long x 7.5cm wide x 10cm high (7"x3"x4")
  2. Weight: Cars have a maximum weight of 140g (5oz).
  3. Drive: Cars cannot have any propulsion, at the start or during the race.
  4. Safety: No loose parts, dripping fluids, hazardous materials or sharp edges.
  5. Parts: Cars may use any parts from home on top of the kit except:
    • machined bearings.

The whole car, including wheels, is measured for Size and Weight. These are maximum dimensions and cars may be smaller and/or lighter. The Parts rule is subject to modification and additional restrictions over time.

The Race


All cars will be scrutineered prior to racing to ensure cars are race fit and comply with the five rules. Any cars rejected at this stage will be given the chance to modify their cars withing the remaining time before the race. Any cars requiring modification after scrutineering will need to be scrutineered again. Any cars modified without being scrutineered again will be disqualified.


The race will take place down an inclined slope at approximately 30°, with a horizontal run-off at the end, one car against another demarked by curbs 75mm apart.


Each race is determined by car-on-car heats. Approximate timing will be taken by stopwatch for the purposes of the records.

The Results

This is where the results will be shown