This Knex bow is great. It's powerful, small, and only uses 4 pieces! Please feel free to mod it, but when you do, tell me. I want to try it out!
Step 1: What You Will Need
You will need:
1 rubber band (I used a #33, but whatever works is good.)
2 orange connectors
2 white rods
1 gray rod or whatever works (not shown)
Step 2: Assembly (part 1)
Put rubber band between orange connector prongs like so.
Step 3: Assembly (part 2)
Put white rod over rubber band and push until white rod is secure.
Step 4: Assembly (part 3)
Bring rubber band around back of orange connector and repeat part 2 on other side.
Step 5: Assembly (part 5)
Now loop excess rubber band around back and bring over white rod so it looks like this. (I flipped it around backwards.)
Step 6: Firing
Put rod (I used a gray one) through center hole and put rubber band on the end. Pull it back and let go to fire. Enjoy!