See a demonstration of the card here:
And here is a video that shows you how to make your own:
Step 1: Download the design files
If you have any problems with the Instructables attachments the files are also available here: http://www.thingiverse.com/thing:16735
Step 2: Required tools and materials
- 16 pennies (or other similarly sized coins)
- Some tape
- At least one 'jumbo' sized paper clip
- Some cardboard or thick paper
The tools you need are:
- A sharp knife
- A printer or other method to transfer the design to the material.
Step 3: Transfer the design
The easiest way to transfer the design would be to just print it directly on the cardboard, but most printers cannot handle that thick of a material, so here are some potential alternatives.
You could print on a normal piece of paper and glue it to the cardboard.
You could cut it out from the normal paper and trace the design onto the cardboard.
Or you could use some kind of trace paper or pen with heavy bleed to trace the design onto the cardboard through the paper.
One thing that you want to check in all cases is that the design is not being scaled to a different size when you are printing it. The overall design should be 3.5" by 4"
Step 4: Cut out the design
The outside shape can be quickly cut with scissors, but the inside lines are more easily done with a sharp hobby knife.
It may be helpful to make some slight notches along the 4 dotted lines that touch the outside of the card to make folding along that line easier.
Step 5: Fold the card
This should form a sturdy shape that will rock on the table much like a rocking chair.
Step 6: Assemble the counterweights
The coin size isn't extremely crucial so small coins in other countries will also probably work. Just use however many coins it takes to make a stack that will fit firmly in the slots at the front of the card.
Step 7: Insert the counterweights into the card
The coins should be a firm fit because they need to be held in place as the card moves around quickly.
Step 8: Prepare the paperclip
I'm not sure if there is much variation from brand to brand, but the box of paper clips pictured above is the brand that I used when designing the trebuchet.
You could probably make your own sling if you wanted to shoot other small objects, and you can also attach objects to the paper clip to fire them.
Step 9: Fire the trebucard
A grippy rubber surface provides the best performance, but it can also be more temperamental to fire on such a surface.
You can adjust the loop on the paper clip (or the shape of the tab on the card ) and make it smaller or larger to alter the trajectory of the trebuchet.
A more detailed video of the operation of this card can be found here:
Step 10: Done? Fold it up
First you need to remove the counterweights by just pulling them out. Then you unlink the center arms and fold them back to the sides. Then the entire sides can fold in, and your paper clip ammo can be used to help hold it all closed.