It's easy to make a solar hot air balloon using normal household items. All you need are a few trash bags, tape, and some free time.

Steps

  1. Separate the 4 trashbags.
  2. Cut off the sealed end (as close to the seal as possible), and find the long edge of the folded bag that is folded several times over.
  3. Insert the blade of a pair of scissors into one of the folds and cut all the way to the other end. You should be able to spread the bag open into a 3ft x 5ft sheet of plastic. Repeat this procedure for all 4 bags.
  4. Join 2 bags together with masking tape, along the long (5ft) side of the sheets. You should have a 5x6ft sheet of plastic. Attach another bag to one of the 5ft sides, and then the last bag. You should have a long, 12x5ft sheet of plastic.
  5. Join the two shorter (5ft) ends with the masking tape. You should now have a flat tube that measures 6ft x 5ft.
  6. Seal one of the open ends with masking tape. This is Seam A. There should be a seam at the center of the new seam.
  7. At the other end of this seam, take the remaining open end and pull it open.
  8. Seal this opening, so the seam is perpendicular to seam A. See how to make seamThere should be 3 corners of the balloon.
  9. Cut about 5 inches off of one of the corners, and invert the entire balloon like a sock.
  10. Use a blow dryer to inflate. The sun will keep the balloon hot and can be flown on any sunny, calm day. A small fan will work, but since this is a small balloon it is hard, especially in wind, to heat up very fast. The balloon should be triangular in shape, or a tetrahedron.

Tips

  • If you can't find the right kind of bags, go to www.solar-balloons.com - you can get yours pre-built for less than ten bucks.
  • Try attaching a message to the balloon and let it go. See if someone finds it and how far it goes!

Warnings

  • Avoid trees, houses or power lines. If a balloon gets stuck in a tree, chances are it will be there for several years.
  • Please check first with your local authorities regarding any flying devices.

Things You'll Need

  • Black 30 gallon trash bags - 0.5 MIL
  • Masking tape
  • Scissors