Laser Cutted Pocket Sized Ballista

All the steps you need to download my pdf and make your own pocket sized ballista!

Step 1: Downloading the Laser Cut Pdf

First, you want to download the laser cut pdf that I am providing for you. It will give you the base of the ballista and all you will have to do after that is install the items to make it work.

Step 2: What to Get

Things you need to have to complete this project:

  • My PDF
  • Access to a Laser Cutter
  • Hot Glue
  • Pliers
  • Small paper clips
  • dental floss
  • 30 mm bamboo skewers
  • small 1.9 cm binder clip
  • Utility knife
  • Card board

Step 3: Prepare the Torsion Bundle

Cut a strap of cardboard to about 2.5 cm wide. Wrap the dental floss around the cardboard 10 times. Do that two separate times and tie both ends to create two loops.

Pinch the waxed loop of floss together, on a end, and then put it into the bigger holes in the middle of the holes. When through separate the strands.

Step 4: Install the Throwing Arms

Cut two bamboo skewers to 8.9 cm long. Also, cut another bamboo skewer into four 2.5 cm long. The 8.9 cm is the throwing arm and the 2.5 cm is the pegs that will wind up the torsion spring. Also, Cut and straighten a paperclip into two 3.2 cm pieces.

Rotate the 2.5 cm winding pegs to create the 8.9 cm throwing arm press into the ballista. When the throwing arm is pressed against the frame, insert the paperclips into the correct hole to prevent it from unwinding.

Step 5: String the Ballista

Split the tip of each throwing arm with the utility knife and slip a 28 cm piece of floss into the slip with about 3.8 cm hanging out one side.

Wrap the short end of floss tightly around the tip of the throwing arm to holes the throwing arm in place. Repeat this on the other side and apply a little bit of hot glue onto the already wrapped floss to prevent it from unwinding.

Step 6: Create the Trigger and Bipod

Hot Glue a binder clip onto the back of the frame. To create the Bipod, cut a craft stick in half at a 45 degree angle twice, and glue the pieces to the ballista as shown.

Step 7: Make the Bolts

Cut another skewer to 17.8 cm with the tip, then fold a 2.5cm piece of tape over the blunt end of the skewer. Leaving 6.4 cm exposed at the end. Then trim the fins (tape) into a fin like shape. The fins must be able to fit through the front gap of the ballista.

Then, straighten a small paperclip and wrap it tightly around the tip of the skewer (Creating a leading weight).

Using the utility knife carve out a small nock at the back of the skewer. The gap must be aligned with the fins.

Step 8: Have Fun, and Fire

Insert the bolt through the front of the ballista, and position the nock onto the string. Hold the back of the bolt in place. Pinch the bolt near the fins, and open the small binder clip. Then, push the bolt into the trigger. Center the fins (bolt), aim, and press the small binder clip (trigger) to fire!

That's it! Hope you enjoyed!

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