Introduction: Laser Cut Trebuchet
A trebuchet is a type of catapult, a common type of siege engine which uses a swinging arm to throw a projectile. The word trebuchet comes from the Middle French verb "trebuch," meaning ‘to tumble’ or ‘to fall over,’ which is exactly what the throwing arm of a trebuchet does when it is released.
Step 1: The Supplies That You Will Need
In order to properly complete this laser cut trebuchet, you will need several different things:
- This Onshape Document
- Onshape is a 3D CAD software that allows you to virtually create a model of a soon to be, tangible object
- A laser cutter or a 3D printer
- Based on my particular design you are able to 3D print each part or cut each on out on a laser cutter
- As my wood of choice, I chose Luan
- I chose this specifically because of the thickness of .189 inches
- This thickness allows the Luan to be easily cut by any laser cutter
- If you happen to chose a different type of wood you will have to modify the dimensions of all the parts in the CAD file (specifically the mesh points)
- Any wood glue will work
Step 2: Preparation
- After properly analyzing the full design you can begin modifying it to your own satisfaction
- Remember, if you modify the thickness of the whole design you will also need to change the length and the outward protrusion of the mesh points
- After the model is modified insert each part into a C sized sheet of drawing paper and create your engineering drawing
Step 3: Transferring to Adobe Illustrator
- After step two is complete you will need to export a PDF file of the final drawing and import it into Adobe Illustrator
- Go to this link for help
Step 4: Assembly
- Now that you have inserted the document into Adobe and then cut it out on your laser cutter you can begin assembly
- Go to this link for help on the tangible assembly
- If the pieces do not quite fit together you can file, sand, and then use the wood glue that was on the list in step one
- When using the Trebuchet, in order to receive the best results, you should have approximately 170 grams in your counterweight, and your projectile should be about 5 grams in weight and 6 inches long in length.
- Any counterweight can be used
- I have made my projectile out of two rubber bands, a nut, and a bolt as you can see in the picture above
- As my counterweights, I have use bolts and ball bearings
Step 5: Final Product
In this last step, I have inserted a video of the final product in action.
Step 6: Design Faults
When analyzing each design you may find that the parts don’t fit together flawlessly. This is because the measurements and dimensions are slightly off; some filing and sanding may be required to assemble the final product. These errors have occurred because of careless measuring.
Step 7: Citations
Some of the information and/or images in this instructable was not my own work. Here are the proper citations crediting the information I have utilized.
“Arms and Men: The Trebuchet.” HistoryNet, 23 June 2016, www.historynet.com/weaponry-the-trebuchet.htm.
Abong.com, director. YouTube. YouTube, YouTube, 19 Oct. 2018, www.youtube.com/watch?v=prfnE_NYrOM&index=2&list=PLYni2YABNDMcOovAMoXULY_R-y4dTlYNk.