This is a not too complicated project that easily modified to use materials you have on hand. For ours we used scrap wood, scrap plastic, and a rubber band from an asparagus bunch! It does require basic carpentry skills, but nothing too usual or complex. You'll notice there are a lot of steps in this instructable, that's mostly because I was trying to be thorough, so don't let it scare you.
This prototype is a single car launcher, but could easily be modified to launch 2 cars at once for racing purposes... that will probably be the next project! It also is designed so that you can attach it to your hot wheels tracks (not shown here).
Hope you enjoy!
Step 1: Materials
A few Hot Wheels, Matchbox, or similar cars to ensure size and for testing.
Block of wood, taller/longer than your cars.
Short screws (4 top, 4 bottom, 6 sides)
4 finishing washers (optional)
I eye screw
Scrap plastic as wide as your wood block, and a few inches longer (or stiff cardboard, or thin wood, or even an old circuit board!)
Scrap clear stiff plastic (either recycled from some packaging, or lexan, or even shrinky dink material) about the size of your wood block.
Rubber bands (at least one, various sizes are nice) We used one from some asparagus.
String or twine (optional)
"Bumpers" (little rubber/plastic feet) for the bottom (see step 11)
Saw for cutting the wood
Dremel or Drill
Business cards or other similar scrap cardstock (try junkmail!)
Sharpie/marker (for marking plastic)