This afternoon we built our first round of table-top catapults. A great turnout and thanks to the parents that helped out. With 15 kids there we ended up with 4 groups building a ‘quick and easy’ wooden catapult… well sort of. Like many projects there were some imperfect/missing parts and since we hadn’t tried the plans almost everyone made modifications. But we were able to get all 4 launching racquet balls in a couple of hours and I heard lots of ideas on how to improve the design.
Learning to use hand saws seemed to be a big hit with the kids, everyone that wanted got to try a back saw or the hand rip saw. I heard several kids comment that they could see why adults like using the power saws! Everyone also got to drill and use power screw drivers to assemble the 2×4’s. We tried both bungee cords and some bicycle inner tubes for the throwing arm. No clear winner with the designs we had, more experimentation is needed for the throwing arm tensioning. One thing we learned, the cup that holds the ball makes a difference – if it’s too deep the trajectory of the ball changes.
I’ll put additional pictures on our catapult project page later & more comments on what we did – the one we built today was based on an Instructables project. It turns out some of the dimensions were wrong and the lengths didn’t add up correctly. But that’s part of the learning, how to adjust when things don’t work and to figure out a way to make do with what you have on hand.
Although the hydroponics group wasn’t there today, they do have sprouts and will be moving them to their float tank soon. Special thanks today to Bob Hershberger for letting us use the Robert Bottoms (Southside) Community Center & to Brian Cox for getting the wood.
Next up for the Catapulters – table top torsion catapults for comparison purposes. And of course the larger group build: the Behemoth trebuchet. We now have a stack of 4×4’s to start cutting mortise and tenon joints along with a trailer for the big one…