Trebuchets were all the rage in the middle ages. This catapult type machine allowed armies to hurdle heavy stones over long distances with tremendous force. Unlike other catapults, the trebuchet incorporates a sling. The sling allows objects to be thrown further and faster than the throwing arm alone. But to get a trebuchet to work to its maximum potential requires having the right kind of sling pouch for the object you are trying to throw. This pouch is quick, easy to make, and can be scaled to whatever size you need.
Measure the diameter of the object you want to throw. Cut out a diamond shape from the canvas. Make the width about 1 2/3 times the diameter and length just over 4 times the diameter.
Cut a small hole about 1 inch in from each point on the long ends. Insert grommets into both holes.
Fold the diamond in half width-wise so that the grommets are together. Measure about 1/4 of the diameter out from the fold and about third of the width down from the point. Sew a line between the two points. Repeat on the opposite side to make a pouch shape. Cut off the points close to your seam.
Measure two lengths of rope the same as the distance between the fulcrum and release hook of your trebuchet. Cut the rope and tie the ends through the grommets of your pouch.
Reinforce the ends of the pouch with extra canvas before inserting the grommets if you are throwing heavier objects.
The larger your pouch the more air drag you will get with a solid pouch.