It’s an ethereal sound, Doppler-like and downright
spooky. “It scared us the first time we heard it
coming at us,” says Kurt Modert, from whose
Minnesota backyard the sound emanates. “Who
would have thought a bowling ball could make
such a sound?”
Modert, with his friends Roger A. Bacon, Ryan
Krueger, and David Proehl, built an enormous
trebuchet on Modert’s exurban St. Paul property.
Enormous even by medieval standards, their
catapult is large enough to throw heavy objects
700 feet into a grassy field, now well-pitted and
cratered from hundreds of high-impact landings.
Photograph by William Gurstelle
The builders are skilled scroungers, picking up
most of the building materials at a fraction of the
retail price. They made the trebuchet frame mostly
from scavenged lumber. The swinging counterweight, the key to any good siege engine, is a
265-gallon oil tank they got for free off Craigslist
and filled with sand.
Still, their investment is at about $3,000 and
growing, much of that going for expensive hardware
and fasteners. But the cost is minor compared to
the joy they get when they hurl stuff.
>> Trebuchet Group: