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My friend Joseph made a crossbow with some wood and surgical tubing, so I decided to make a tension bow for myself. It turns out that it was incredibly cheap and works pretty well too. The total cost of the bow is just over $2, and the cost per arrow is just over $1.

This one's easy enough that even I can explain how to do it.

• 4-ft fiberglass rod
  $2 at Home Depot or Lowes. Look in the mailbox or sign aisle, the real use of these things is to stick into the ground to mark pathways (for snow?)
• 3-ft 1/4" or 5/16" wood dowels
  $1 at Home Depot, Lowes, or a craft store
• Heavy-duty twine, or something stronger (cotton string won't work, don't think nylon would either)
• 2" wide masking tape

1. Drill two 8th inch (or smaller) holes at either end of the fiberglass rod. Make sure they are facing the same way, and don't breath the dust.
2. To string the bow, double-knot some twine around one end, bend the rod, and double-knot the other end. This takes some practice. You should have ~4-6" between the string and the bow. Any less and your twine will break on the first shot.
3. Notch the end of the dowel with a model saw, small back saw, or hack saw.
4. Make some fins with masking tape on the notched end.
   1. Cut 3 pieces of 4" long masking tape.
   2. Lay one lengthwise along the dowel at one end, and lay the dowel on the table, sticky side of the tape facing up.
   3. Put another piece of masking tape the same direction as the first, but so the sticky sides face each other. Make sure only half of the sticky sides are touching each other.
   4. You should have two halves of the sticky sides still not stuck to anything. Place the third piece of masking tape over them, completing the triangle. Press down the tape around the dowel so that the fins are tight.
   5. Trim up the fins into uniform rectangles. This makes the next step easier.
   6. Trim the fins into a fin-shape.
5. Stick the non-finned end of the dowel into a pencil sharpener, and sharpen until it's nice and sharp.

I recommend shooting into some cardboard boxes. The thing's pretty accurate and shoots plenty far enough for me. Of course, don't go pointing this at people, a sharpened wood stick is very dangerous going at these speeds. Now, this is a fiberglass rod, so it can bend pretty far back. However, I wouldn't pull farther than about 6" from the string to the arrow tip. If one of these snapped while you were holding it, you'd probably be going to the hospital. Don't be shy, but don't be overzealous. Don't store the bow strung. I've never had to un-string mine, the twine always breaks on its own. If the twine stretches so it comes 3" or less from the rod, it's about to snap. Firing the bow empty also causes it to snap easily. There's no danger in the twine snapping, you don't feel anything. As usual, I have no details on the power of this bow, but it shoots maybe 100' at a 45 degree angle.