Some modifications on the basic knex cannon. Adding a more realistic trigger device, and a handle. An d a bit of extra power.
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Step 1: Gather Parts
Here is a list. About half way through making it I decided to replace 1 of the grey end clips with 2 blue spacers instead. But either way can be done.
I messed up, add 1 red rod to the list of needed parts.
Step 2: Barrel
The barrel is 2 long grey rod with 6 reds at the end of them, then the 2 blue spacers(or one grey end clip if you don't mind it sticking out at an odd angle) on one rod, and an organge piece with a white rod in it as the jam blocker.
Step 3: Ram Rod
Yellow rod with a grey end cap,this is what the rubber bands will go through. Orange connector is what you pull on. It isn't needed, but makes it easier to pull. Then two grey end connectors pointing at angles that will keep the rod in in place. These will be fed onto the grey pieces in the barrel
Step 4: Handle
The handle is a yellow rod and a blue rod with 6 white connectors between them.
Step 5: Handle Connection
First thing is notice the grey end connnector on the far left, that is the end of the ram rod. You must insert that before you do this step. Now to the actually barrel connection. It is 1 white connector and 4 red connectors pushed all the way to the oppoite end of the barrel. Then connect the handle as shown in the last picture.
Step 6: Trigger
The trigger is fairly simple. Just a red rod with an orange piece cliped to it, and a grey end connector fed onto it. To connect the trigger connect one end to the opposite side of the orange piece as the ram rod blocker and the grey end cap tha is fed onto the red rod to one of the grey rods of the barrel. You can play around with what angle you want the orange piece to sit at, this is what you will push in order to fire.
Step 7: Bands
I was working with pretty average sized rubber bands what I did used 4 of them. I looped 2 bands together then fed that through the end of the ram rod and wrapped it around the end of the barrel, and did this on bothe sides. Then one of the bands on the left side wraps over the ram rod blocker. The picture shown is in the cocked position.
Step 8: Fire
To load: after cocking insert desired ammo into the end of the barrel(white rods are what I use, but the tiny green, or blue rods would work as well.)
To fire just push the orange pice of the trigger over which will move the ram rod blocker out of the way.