F2K Trebuchet

thingiverse

This is an f2k style floating arm trebuchet. My kid loves launching stuff with this thing, but he needs help loading it up for office wars. We can adjust it to launch objects high over cubicle walls and vanquish our opponents in no time. One of these days I'll post a video of it. The frame stands about 8" tall by 12" long. It can easily launch the small golf ball included in the files a good 25-30 feet with the right sling/pin and counterweight combination. This must be printed in pieces and assembled, requiring some hardware and other items for assembly. Press fits are designed for 608-2rs bearings. What to print: * Base_front: 1x * Base_rear: 1x * Frame parts: 4 total (1 of each) * Arm: 1x * Top pieces: 2x * Trigger shaft: 1x * Trigger wheel: 1x * Wheel 1: 1x (optional) * Wheel 2: 1x (optional) * Wheel 3: 2x (optional) * Wheel 4: 2x (optional) * Ball: As many as you want (optional) What to Buy: * M8x150mm threaded rod: 1x (I used the one from the spool holder that came with my printer) * M8x80mm bolt: 1x * M8 washers: 4x (to retain any larger washers used for counterweight) * M8 nut: 9x * Large washers: 10-14x (25-40mm outside diameter, for counterweight) * Thread: 2 meters or so, for sling * Cloth: 40x80mm ish, I used microfiber, for sling * Paper clips: 2x (medium-large size) * M4 or M5 washer: 1x (for sling to pin connection) * 608-2rs bearings: 3x Assembly: If you printed the wheels then snap them onto the bearings. Press two of the bearings with the small wheels onto the arm shafts. The other one goes on the M8 bolt at the rear of the frame. The frame is intended to be pressed together. Center the M8 threaded rod on the arm and retain it with nuts. Add counterweight. Slide it into the center slots on the frame and install the top pieces. For the pin, cut a 50mm long piece of paperclip, heat it up with a lighter, and press it into the small hole on the end of the arm. You will need to play with the length and angle of the pin to get the ideal throwing arc. For the trigger, use another paperclip and bend it/cut it to the proper length. The sling is a rectangular piece of cloth with holes in each corner, and 150-200mm thread doubled up for each side. One side of the sling is attached to the thru hole at the end of the arm, the other is attached to a small washer that goes around the pin on the end of the arm. You'll figure it out.