Floating arm trebuchet (dimes and pennies)

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This trebuchet uses a floating arm instead of a fixed arm, which means the weights can fall completely vertically, resulting in a more efficient and powerful throw compared to standard trebuchet designs. Check out this test firing shot: http://i.imgur.com/9QZHuB0.gif Assembly is relatively straightforward. You will need 2 toothpicks and 2-3 lengths of string, along with the 3D printed parts. Print two of each part: the weights, the stand, and the wheel. Everything else just prints one time. Be sure to orient each shape properly, as I didn't build them on the plane they were meant to be printed at. I printed the parts at a height of 0.025mm with a width of 0.05mm. Some parts are small, measuring exactly 1mm in width, so these settings ensure that they match up perfectly with no small gaps. Side1 and side2 should be pushed together until they're flush. This might take some effort, but it's essential to keep them in place and prevent them from coming apart. I used a small vice to push pins together that I couldn't get with my hands. The stands simply snap onto the assembled frame. The sling snaps together once the two halves are attached. Make sure they swing freely after assembly; if they don't, you may need to make some minor edits to the file to configure it correctly for your printer. These small pieces can vary slightly in size, so some adjustment might be necessary. For the arm, take one of your toothpicks and cut it in half. One half will serve as the firing pin; save that for later. Cut the other half down to 9mm in length and insert it through the second hole from the top of the arm (the thickest end). Next, push the two wheels onto each end of the toothpick. The other toothpick secures the weights and the arm to the frame by passing through one vertical slit, then the topmost hole of the arm, and finally the farthest slit. Once this is complete, you can slide the weights onto each side and fill them with dimes. You could increase the size of the weight holders if you prefer to use pennies or other denominations. For the string, one piece goes through the bottom most hole of the arm and then through one of the string holes on the sling. Another piece must be made into a loop on one end and attached to the other string hole on the sling. When loaded, the sling should be centered in the frame with the strings taut. If it's too long, it won't have enough power to swing the strings; if it's too short, it will throw your coins into the ground every time. Experiment a bit to find that sweet spot. If you encounter any issues, simply look up how trebuchets work and you should be able to figure it out.