Some time ago the series 'Scrapheap Challenge' had been on in the UK (I think in America it was shown as 'Junkyard Challenge') and I watched it avidly. The basic format was for two teams of reasonably good engineers to compete in a seeded junk yard and be given a day to build whatever the presenters had cooked up for them. Sometimes it was a diving bell, other times a hovercraft. The series really appealed to my admiration for amateurs building things normally only professionals would attempt, and showing the gap is not as large as one might think.
Anyhow, the final of this particular series pitted a team of car designers from Jaguar sports car manufacturer against a team of farmers from Dorset. Both had won all their particular heats to reach the final and both teams were hugely entertaining. The task this time was to 'project' a de-engined Mini as far as possible through the air. No specific method was suggested and they'd have three tries to get the longest distance.
The Jaguar bunch decided they would catapult the Mini from a flatbed truck using some really strong elastic.
The Dorset farmers said "Lets build a Trebuchet, I always wanted to build a Trebuchet". Truly a mad suggestion. They made their life-size Trebuchet out of telegraph poles the size of street lights. ( For a brief Trebuchet experience, please visit 'Trebuchet.com' listed on my home page). After some initial difficulties which required dismantling some of the film set to get this enormous construction onto the test range the scene for the confrontation was set.
The Jaguar Team went first and propelled their car chassis a few metres off the end of their flatbed truck. They went back to their calculations and doubled the strength of the elastic.
Next came the Dorset farmers; although there was a small wait whilst the rubbish skip they used as a counterweight was filled with ingots of lead using a forklift truck. Imagine the truly awesome weight of a 3 cubic meter skip filled with lead !
They pulled the trigger and the beast swung into action. The mini rose into the air. The telegraph poles exploded under the pressure. The mini flew a few yards backward as the structure collapsed into a pile of splintered timber and bent steelwork.
The Dorset farmers laughed until they were hoarse. I laughed too and the announcer drolly agreed that the direction the Mini should travel in was not important and the farmers were in the lead. Of course they lost because the Jaguar team still had a working device, but that wasn't the point.
It got me thinking that it all looked tremendous fun and looked into a scaled down version capable of hurling water filled balloons. I finally decided on a scale model of Edward 'Hammer of the Scots' siege engine the War Wolf .
After three variously bad attempts I finally made one that worked. The counterweight is a wooden bucket capable of taking ten house bricks and it happily hurls 1lb water balloons clear over my house to the road beyond. Of course, I can't see the road from the back garden of my house so visitors being 'entertained' to some hurling need to provide a road clearance check before firing. Luckily my nephew and niece thought this was fun and spent a lazy summer afternoon trying to catch the balloons as the randomly appeared over the roof before exploding on the pavement.
The War Wolf (or perhaps more properly the War Puppy) is currently laid up in my garage awaiting another excuse to pepper the street outside with burst balloons.
... It turns out that potatoes hurl well too. I've now played potato cricket in the garden with the treb acting as bower. I'm tempted with golf balls but need a really big empty space to try that one.
War Wolf Media
Below are a couple of shots of one of the prototypes being built and a short movie of a firing. I'll update with better stuff during this summer.
