Interesting that you should mention Trebs- last month our school had a
"baloon launching project" for all the eighth grade physics classes, about
90 kids. Any machine could be built except air cannons and slingshots ( no
unlimited category, all one class ; ) parents could help and some of the
dads really got into this. The teacher asked me to help him make an example
to give the kids something to shoot for so I designed and built a trebuchet
out of 3" square tubing with pillow block bearings, inch and a half diameter
shafting for an axle and adjustable counterweight ( weight-lifting free
weights ). We only went a 'little' overboard because we almost got beat by a
catapult with seven garage door springs having 60-70 pounds pull each. The
catapult had to be mounted on a small trailer to keep it from violently
bouncing around when he released it. Our treb needs a lot more tuning but we
were able to uphold the schools honor with the furtherest 'hurl'. Really-
that's what it's called- The Great Sport of Hurling. Do a web search and you
will be amazed. The catapult did 105 yards.When I saw that I put another 70
pounds on the counterweight and hurled a two pound grapefruit 115 yards.
Next year the football field isn't going to be long enough! I almost hit the
school building.
As for the web game- five minutes and a dismal 2114. I'm better with hands
on stuff.
Glenn in West Texas
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