How to Build a Torsion Catapult

Introduction: How to Build a Torsion Catapult

This is how you can make a Torsion Catapult.


[x2]Board A=3 feet

[x2]Board B=2 feet

[x2]Board C=1.5 feet and ½ in.

[x1]Board D= 2 feet, 3 in.

[x4]Board E= 16.25 in

[x1]Board F= 2.5 feet


{PVC Pipe= 5.5 in

4-8 Lag screws

2-6 Bolts

Step 1: Cutting Wood

Cut all the necessary pieces of wood to build this to their lengths. You may label the pieces of wood and it’s sides if you think it will help you understand these instructions better.

Step 2: Drilling a Hole

Take both Board A’s and drill a hole through Side A. These holes should be 2 and a half feet from one of the ends of the piece of wood. The hole should be big enough to fit some rope through it.

Step 3: Making the Base

Use a lag screw to screw Board A (Side B) on to Board B (Side B) perpendicularly to each other to make an L shape. [x2]

Use lag screws to attach the finished pieces of wood together to make a rectangular piece of wood (the wood should not fill in the middle of the rectangle). This is the base of the catapult.

Step 4: Attaching 2 Pieces of Wood to the Base.

Place the rectangular piece of wood on Side B.

This next step will be taking place in the middle of Board A (16.25 inches on each side). Use a lag screw to screw Board C (Side A)to Board A(Side A). Board C will be bolted to the outside of the base of the catapult. Board C should also be touching the ground. Repeat this step to the other side of the catapult as well.

By now you should have a rectangular piece of wood with 2 pieces of wood bolted to the side, going upwards.

Step 5: Adding Wood in Between Wood From Last Step.

Now using the two new attached pieces of wood, take Board D (Side C) and stick it in between both of the Board C’s. Use lag screws to screw Board D (Side C) and Board C’s (Side A) together. Make sure both of Board D (Side C’s) are screwed in.

Step 6: Diagonal Pieces of Wood

Now for the diagonal pieces of wood. You should already have 4 pieces of wood that are 16.25 inches (1 foot and 4.25 inches) . Line up one of the Board E’s at the very end of Board D (Side A) and the base of the catapult and attach them using bolts or lag screws (do whatever you think will be best). These won’t fit perfectly together so cut off the corners of Board E so they can fit together with the rest of the catapult. It is more important that Board E lines up with the top of Board D so Board E will most likely not reach to the end of the base of the catapult. Screw these pieces of wood in.

Step 7: Connecting Base and Piece of Wood With Rope

Now, there should be one piece of wood left. Make a hole through the Side B of Board F. This hole should line up with the other two holes made in Step 2 when standing vertically. This hole should also go all the way through the board.

Take a piece of PVC pipe and cut it into two 5.5in pieces. Secure the two pieces of PVC pipe outside the base of the catapult next to the hole in the wood (from step 2). Now for the rope part, watch “How to wrap the rope on a torsion catapult (Mangeol)” by epicfantasy on YouTube. When you have finished wrapping the rope, you can screw the PVC pipes in if they don’t stay in place. If they stay next to the base of the catapult and don’t start unraveling, you don’t have to screw them in.

Step 8: Testing the Catapult

Now when you move Board F (the board attached by rope), the tension in the rope should make the board accelerate forward. Now glue a cup to the top of Board F on Side A. Now if you put a tennis ball in the cup, the tennis ball should be thrown forward and if it doesn’t, then whoops.

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