Get yourself some 6″ craft sticks (you could use 4″ popsicle sticks, but the short length changes things..like how easy to assemble and flexibility) and some rubber bands (not long ones, but sturdy ones – 2.25″-3″). You also need a plastic bottle top or small paper/plastic cup. And of course some projectiles.
Catapult 1
This one is simple. I used 12 craft sticks and 3 rubber bands.
Wrap 10 craft sticks together, slide 11th one between the bottom and next one up.
Use a rubber band to attach the 12th as a launch arm to the 11th
Glue a pop top/cup onto the launch arm.
To launch :
hold down block of 10 sticks with one hand
pull launch arm down with finger on other hand
Variables :
slide launch arm further in/out of the block of 10
add more sticks to the block of 10 (or remove)
make launch arm longer (attach another craft stick)
make launch arm stronger (attach another craft stick to make thicker
Catapult 2
This one is a little more difficult to put together, more parts, tension pulling things in…
Also, as designed it shoots too low.
It takes 11 sticks and 16 rubber bands (if I counted correctly)
I don’t know/have a special way to wrap rubber bands around sticks…some mix of over, under, twist, around…
Make a square base and two uprights
Attach the uprights to the base.
They will want to fall in because of tension.
attach a top cross bar to the uprights
attach a bottom cross bar
(double up rubber band on the cross bar, wrap around the upright to connect back to crossbar)
Put launch arm in front of bottom cross bar, but behind top cross bar
Put rubber band around the bottom of the launch arm and wrap it around the back of the square base (this is your tension)
(You could try more than one rubber band here to adjust tension)
Glue projectile holder to launch arm
To
launch, hold the base with one hand and pull back on launch arm with finger of other hand
As designed, it shoots too low, so you get very little distance
You either have to angle the front up somehow
or
you need to make the launch arm stop sooner— maybe instead of a cross bar on top, we attach it lower…
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