Sometimes, with no plan aforethought, the forces of the technological economy collide with the dynamics of childhood.
The tire swing is one perfect example of: a piece of dual-use technology, recycling, imagination, simple harmonic motion and the fun-ness of speed.
- Find a vehicle tire. Car tires are perfect for kids. Adults might want to locate a truck tire. Note: If you are getting a modern tire, be sure that the belts are not showing through the rubber, unless you like nasty metal splinters.
- Find a good, stout rope with a tensile strength capable of supporting:
(the weight of the tire + the weight of the person using the swing) * 3.
- Find a nice solid tree branch, at least 7' or 8' off the ground for a kid's swing or 10' for an adult swing. Make sure the branch can handle the same weight as above without breaking.
- Tie one end of the rope around one section of the tire.
- Tie the other end of the rope around the tree branch. Make sure your knots can handle both the weight as well as being pulled back and forth (rotated) around the branch.
- Pull back. Let the tire take your weight. Holler with delight.
The tire swing is a quick, cheap and simple means of providing the active imagination with anything from a horse ride to a spaceship. It can be ridden sitting through the tire and holding on to the tire or rope, or 'lying' through the tire on one's back or stomach (stomach for Superman fantasies is recommended). It can also be ridden standing on the top curve of the tire, holding the rope, if the swing is tall enough.
For maximum enjoyment, place at the shore of a pond or river near a spot deep enough for diving. Swing out over the water and slip the surly bonds of earth before taking the plunge.
For a more predictable (straight) path, use two ropes and tie them around 70 degrees apart on the tire, then tie them to the branch such that they and the tire form a triangle (i.e. run the ropes straight out from their attach points).
For maximum dizzyness, rather than swinging, get in the tire and twist around as many times as you can before taking your feet off the ground and letting the tire spin you madly back. Attempt to not vomit. (Educational moment! XWiz points out that this is an awesome way to demonstrate conservation of angular momentum. While spinning, pull your arms and legs in close. Note that your spin rate increases. Throw them out as far as you can to slow your rotation (and, if necessary, avoid tossing your cookies...if you fail, pull them back in and maximize your spray pattern!)
For heavy tires and people, and for maximum sturdiness, consider using chain rather than rope.
For use as a salutary demonstration project, see http://www.scaryideas.com/Cartoons/ITProjects/ (many thanks to themanwho for this reference).