Desk Catapult

If you have access to a laser cutter and want to shoot stuff with a catapult at your co-workers, you will definitely enjoy this project.

This little guy is originally known as “The Backyard Ogre”. I would be lying if I said the design was 100% mine because I’ve seen a picture of the catapult on a website once and since then I’ve dreamed of making it myself, thus came my own laser cut mini-version of it. It’s pretty durable and strong, shoots really far if you use good rubber bands.

The design in the file attached is for 3mm sheets. You can use different thickness but you’ll have to make a few modifications to the design so I suggest you read through the Instructable and try to understand how the parts go together then it should be easy to modify the design to your liking. Don’t hesitate to contact me for questions.

Enough with the introduction, let’s do this!

Step 1: Materials Recquired

• One of the files I have attached as CDR, DXF or PDF.
• 3mm sheet of wood/acrylic/whatever you want to use.
• Yellow glue or super glue.
• Rubber bands.
• Access to a laser cutter.
• Sandpaper (optional).
• Software : Corel Draw or any laser cutter software you use.

Step 2: Laser Cutting the Parts

Obviously!

Step 3: Gluing the Pieces Together to Create the Full Parts

I suggest the first thing you do is arrange the pieces on your working table and put together all the similar ones so it is easier for you to recognize them in the pictures.

I numbered the pictures from 1 to 7 so you can easily track each part’s creation.

1) ARM: You just have to glue the 4 pieces to each other while making sure the 4 holes are centered. If the glue gets messy and some of it gets in the hole you need to remove it before it dries.

2) HOLDER: Same thing here, you just need to glue the 2 empty circles on the full one.

3) FULL ARM: Now you just glue the Holder to the Arm and voila, you have the Full Arm!

4) TOP: Glue the 3 tall rectangles to each other, that is it.

5) FRONT/BACK BASE: The 4 small rectangles are the Front Base of the Catapult, just glue them to each other. The 4 small incomplete rectangles are the Back Base, also glue them to each other.

6) SUPPORTS: You should have 8 hook-like looking rectangles, 4 small and 4 bigger. 2 big ones go with 2 small ones. Start by gluing 2 small ones to each other and 2 big ones to each other, then glue the 2 couples to each other while making sure the 4 hooks are aligned. Repeat the process for the other 4 pieces of Support.

7) RIGHT/LEFT BASE: Like the Supports, you can glue this part in 3 steps. Both of the 3 different pieces to each other then combine them to create the whole part. Then repeat process for the other Base. It's really important that you align the little square holes and not get glue in them.

Finally! Now you have the complete parts! Next step is gluing the parts together to create the Catapult. Before you do that though you can use sand paper to clean up the parts if there's glue all over the place.

Step 4: Gluing the Parts Together

1) Base + Support: The space in the Base is where the Support goes. They should interlock. Make sure the square holes are aligned.

2) Complete Base: The complete rectangle goes in the front where the square holes are while the incomplete one goes in the back.

3) Top: The Top part is glued behind the hooks.

4) Arm: Finally, pick one of the super small rectangles and slide it in one of the hole, then through the Arm, then through the opposite hole.

LAST STEP: Your rubber bands should go inside the hook and around the Arm Holder. DONE!

Step 5: Notes

1. There are 2 series of holes for different shooting angles, that's it. One shoots far and the other shoots strong, pick wisely.

2. The super small rectangle that the arm rotates around can sometimes break if you use more than 4 rubber bands, that is why I made some spares. If you want more power I suggest you put a nail or a metal object, it shouldn't break.

3. Aim at your boss.