Cardboard Catapult

2,345

38

5

Introduction: Cardboard Catapult

Hi!

This is a really cool catapult that really works, too!

Catapult Tools

· Hot glue gun, ruler, box cutter or scissors, pen or pencil

Catapult Materials

· Qty. 1 Rubber band

· Qty. 1 Marble or small ball

· Qty. 1 Wooden dowel (12” long, ¼” diameter)

· Qty. 4 Popsicle sticks (1” x 8”)

· Qty. 4 Popsicle sticks (1” x 4”) made by breaking two 1” x 8” popsicle sticks in half

· Qty. 1 Corrugated cardboard rectangle (12”x 4”)

· Qty. 1 Corrugated cardboard rectangle (3.5” x 3”) with ¾” x ¾” squares removed from two corners as shown

· Qty. 3 Corrugated cardboard rectangles (4” x 8”)

· Qty. 4 Corrugated cardboard right triangles (base = height = 6”)

· Cellophane tape

Step 1: Build the Fulcrum

Glue two of the 6” triangles together using hot glue. Do the same with the other two 6” triangles.

Step 2: Assemble the Base of the Catapult

Glue the three 4” x 8” rectangles together using hot glue.

Step 3: Make the Arm of the Catapult

Fold the 12” x 4” along its length to form a tube of square cross-section . The tube is 12” long and has four 1” wide sides. Glue the tube along the 12” edges.

Step 4: Form the Catapult Projectile Holder

Fold the sides of the 3.5” x 3” cardboard cutout to form a box. Hot glue the sides together to hold the shape of the box. You can use tape to hold the box together while you apply the hot glue.

Step 5: Make a Brace for the Bottom of the Catapult

Glue two 1” x 8” popsicle sticks together and glue them perpendicularly to one of the 4” edges of the 4” x 8” cardboard.

Step 6: Install the Reinforcement Sections for the Bottom of the Catapult

Glue two of the 1” x 4” popsicle sticks together using hot glue and glue them onto one of the centers of the long edges of the 4” x 8” cardboard. Hot glue the other two 1” x 4” popsicle sticks together and glue them on the other edge of the 4” x 8” board.

Step 7: Make the Spring Retainer

Hot glue the two last 1” x 8” popsicle sticks together and glue them perpendicularly onto the center of the last edge of the 4”x 8”board. The sticks should stick out about 5” or 6”.

Step 8: Install the Fulcrum

Hot glue the triangle cardboards to either side and on the topside of the catapult bottom.

Step 9: Fabricate the Pivot

Make small holes in the two triangles near the tops and make a small hole in the 12” long tube so that the tube sticks out over the popsicle stick about ½”. Put the dowel through the triangles and the tube.

Step 10: Install the Projectile Holder

Hot glue the box onto the end of the tube that is opposite the popsicle stick that sticks out.

Step 11: Install the "Spring"

Put the rubber band around the tube and the popsicle stick that sticks out. Use cellophane tape to hold the rubber band in place.

Step 12: Enjoy!!

Put the marble into the box and push the box down. When you let go, the box will fly up and the marble will fly across the room.

Back to Basics Contest

Second Prize in the
Back to Basics Contest

1 Person Made This Project!

Recommendations

  • Make it Fly Challenge

    Make it Fly Challenge
  • Fruit and Veggies Speed Challenge

    Fruit and Veggies Speed Challenge
  • DIY Summer Camp Contest

    DIY Summer Camp Contest

5 Comments

0
nielshenriksen
nielshenriksen

4 months ago

Dont use marbles. Use paperballs or other soft balls. Marbles can hit hard.

0
miwhalki
miwhalki

6 months ago

Maybe the holes should be made after we glue the triangles together. Stack em and make the holes before you glue em standing up.

0
elinorrowberry
elinorrowberry

8 months ago

I love this! Making it tomarow!

0
wannabemadsci
wannabemadsci

9 months ago

Congratulations on being a finalist in the Back to Basics Contest!