Cotton reel tanks

An oldie but goodie, cotton reel tanks are great fun. Add your own tweaks and race them!

Step 1 What you need

Erm... what's in the picture:

- a cotton reel
- a rubber band
- a pencil
- a match

plus sellotape, scissors etc

(For advanced models you can add extra stuff - but this will do it)

Comments

[costajules]

If it just jumps around and throws the pencil at people, it is because there is nothing to limit the speed of the rubber band unwinding. These things need something to provide a delicate amount of friction. A washer carefully made of candle wax as marcusmorris says works nicely. Normal washers don't, and I can't see cork ones working great either.

[marcusmorris]

In my day we used candle wax for the escapement mechanism - nice, slow and controlled. Also, we cut notches in the rims of the reels so the tanks could climb obstacles. We used penknives for this purpose. Every schoolboy had a penknife back then (indeed the UK Scout movement insisted on it) but perhaps it is more prudent to suggest the use of a file or a junior hacksaw in these modern times where the possession of anything vaguely sharp is considered by the authorities to be highly anti-social and the slightest bloodying of a finger is sufficient reason to take a knife manufacturer to court for failing to print an appropriate warning on the item.
Enjoy the video!

[yeracs87]

Made them as a kid 40 years ago but called them spool bugs. Try using an already used wooden match instead of the pencil. Less weight goes easier around on the floor.

[rubberchicken]

lol how about an unused match!

[toucan]

Ya like a chostick a thin one though

[musicalbee2003]

Mine just jumps around and throws the pencil at people! Whats wrong?

[J_SCAP]

theres nothing wrong you just made a sweet tank wepon that can poke peoples eyes out :P

[Orchestrapit]

Try not winding it as tight or slackening the band.

[meddler]

Neat, i think i'll make this with my son and have some fun.

[Katharis]

Nice! But I dont think that the pen is the best thing to use here. A small lightweight stick should be ideal.