Marble Trebuchet

This is a rough 1/8 scale model of my teams entry into Punkin Chunkin ( http://www.punkinchunkin.com/ ). There is a good deal of tuning which goes into a trebuchet and it's difficult to work it all out full scale since we only get some many shots between repairs. This model is to facilitate tuning work. Also just for fun. We enter purely for fun and our budget it way on the low side to be competitive but that's no excuse not to tune up.

At full scale the treb is 12 feet tall to the pivot and uses 1000lbs (1400 with add-ons) counterweight to throw 8 lbs pumpkins. Simulations show a maximum range of a bit over 800 feet. Our best throws are only a bit over 400.

At 1/8 scale it's about 18 in tall to the pivot, uses 2lbs counterweight and throws .25 ounce marbles. The first few days of throwing show a range of about 55 feet. The simulated max range is about 100 feet so there is tuning to do.

Give enough time I would like to add a more efficient whipper style arm to the model/machine.