This is a series of easy to follow images that show how to build a simple knex crossbow.
It fires well and accurately, but to get the right length of elastic band you may have to tie elastic bands together.
You will need:
elastic bands (big and small)
It took me 2 hours to design, build and modify.
Step 1: Trigger Mechanism (top View)
The cogs can be held in place by small elastic bands.
Step 2: Trigger Mechanism (bottom View)
Step 3: Loading and Firing.
push the trigger into firing position, pull the elastic onto the tape and attached to the small red snapped band, then pull the trigger.