The idea is to make a 3 or 4 wheeled 'car' what can propel it's self forward
using elastic bands and race them!
Stuff needed
4 old CD's or DVD's per car
15mm speed fit pipe from B&Q. A 2 meter length cost £2.34.
Their code was J1712.
Washing powder boxes, cereal boxes etc. If you can't get hold
of any of these, just use bits of card from a cardboard box.
Small nails (tacks) or drawing pins
A knife or sharp pointed scissors (for cutting holes)
Elastics bands
Stapler
Sellotape
How we made it
Step 1
Get a washing power box and cut it in half
Step 2
Cut the speed fit pin into about 10 cm lengths. On the stuff I bought it
had marks on it - I cut the pipe on every 5th mark.
With a little bit of effort you can get the CD's onto the end of the 10 cm
length's of speedfit pipe. It should be a tight fit.
Note I also wrapped elastic bands around the CD to give better 'grip'
Step 3
Cut some holes in the side of the box, big enough for the pin to go
through. Note it works better if the holes are too big for the pipe.
Step 4
Before you fit the 'drive wheels' nail in a small tack (or push in a
drawing pin) to the middle of the speedfit pipe
Step 5
Once you've put all 4 wheels on, attach another pin or tack to the outside
edge of the box.
Attach one end of the elastic band(s) to the tack on the speedfit pipe and
the other end to the tack on the box
Note that we chained together several small elastic bands to make this big
one
Step 6
Once the elastic is attached, use the CD to 'wind' the elastic around the
pipe. When you let go, the wheels should turn!
Note that once the elastic has unwound, the elastic should come off the
speedfit pipe. This is to stop it acting as a brake - one reason why a
tack works better than a drawing pin.
Other ideas
On reflection, it's probably slightly safer to tape or staple the elastic
band to the side of the box. That way, the pin / tack will not be able
to fall out / get catapulted across the room!