In early October, 2007, Costa Mantis came by because he is filming a movie called "Flying Pumpkins". He wanted to hang out with us,
see us work, and hopefully see Mr. B shoot a pumpkin... though we didn't have any pumpkins ready for shooting. For us it was all about
testing out our new trunnion mount hydraulic cylinder which should allow us to wind our machine more quickly.
The flying pumpkins movie now has a web site at Flying Pumpkins The Movie.com.
Sadly, it was a bit rainy on October 7th. Before the crowds arrive Mr. B sits forlornly in my field. The 14lb rock that did
so well last summer for the DVD from the History Channel.')">2006 History Chunk we did for Man Moment Machine sits on the fencepost.
Jeff sets up his computer and webcam. He rigged up a spiffy time-laps video of what it takes to set up and fire Mr. B. The little
camera took one picture every 2 seconds, which works out to about 4 minutes of video.
Then Dave arrives with our new trunnion mount! Dave spent yesterday welding it together, and getting things fitted just-so.
The new trunnion has an inch and 3/4 threaded pin that goes through the scutula. A steel tube provides support for the hydraulic cylinder.
We then drill the four holes needed in each scutula using Dave's cool Magnetic base drill press. Dave didn't have any 1 3/4" hole saws
handy, so a special order bit was delivered just in time so he could drill out these holes.
You can see Costa filming the fun in the background.
Jeff test fits the trunnion onto the scutula. A perfect fit. In this picture you can see the half-pipe a bit better where the
hydraulic cylinder will sit.
Time to raise the bundles so we can do a test-wind with the new system. It was a bit slick out due to the rain, so we had a few
fall-backs as the bundles slipped backward and had to be re-pulled forward.
And there it is! A quick strap in with a nylon ratchet strap held it in tight. We were forced to use our old red cylinders
because the yellow ones we wanted to use ended up with too-big a piston rod. We did get those cylinders out today, but I didn't get
any pictures. We hadn't opened those cylinders up since around 2000.
Roger and Eric lift the new trunnion/cylinder combo into place on top of the machine to put in the next 90 degrees of winding in.
This getup probably ways in around 50lbs now.
Roger watches as our hydraulic pump pulls in an extra 20 degrees into the bundle. Since we are still using our short cylinders, it
takes 4 yanks to get that 90 degrees into the system.
And lets try that again on the bottom! We put 90 degrees into each bunch in a couple hours. One huge advantage to our system this
time is that the cylinder is actually in-line with the torsion arm. This puts less stress onto the arm, and will hopefully let it last
longer.

Jeff was running the hydraulic pump for the winding. We use hand signals to communicate. We have a plan to fix that.
And as his T-shirt suggests, watch out. He does have a catapult, but I'm not sure if we'll be able to hit your head with a rock.

Twist twist twist. Hey, how about some more twist. We really need to make this process go faster. As you can see though,
it's apparently fascinating to watch!
Time to shoot the rock! The sun was falling behind the trees, and we didn't have much sunshine left. As we were using our test-pouch
instead of our competition pouch, this pouch is much larger from our older experiments. We have since learned that a good
pouch for a ballista is much smaller.
Pull the system back. We hit around 900lbs of pullback. Very wimpy! We didn't have enough daylight left to put more twist in,
so we just went for it! The rock was too heavy, and the pouch drooped into the scapus, made a big noise, and sent sparks off.
Sadly, Roger and Dave had to go, so we threw a bucket load of apples after that a few times, but it was too dark to get a good
picture.
We also pulled out Baby Hatra Ballista so we could drop a few little apples out in the field.
Deployment Time Lapse Video
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MetaCafe Video Service
Mista Balista - A Modern, Steel And Compoisite, Full Sized, Anc Video
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Information:
Mista Ballista is a modern adaptation of a 4,500 year old Greek war machine. Resembling a giant crossbow, the arms of the bow are 30 feet (10 m) tip to tip. With a winch, the bowstring is pulled back 20 feet (6m) with a strength of 3.5 tons. A hydraulic system raises the machine to best firing angle, and the ammo is loosed.
In 60X time lapse, you will see it transformed from 4 tons of steel, folded flat, packed for travel on its integral trailer, to in battery, ready to fire. Then, in real time, see it take out a wall of pallets at 80 yds (75m). with a single 17lb (8kg) stone.
The machine was built from 99.98% (by weight) post consumer recycled materials (aka: scrap steel), fired, and rebuilt by Team Tormentum. It can be seen in action, live at the annual world champion "Punkin Chunkin" event, held in the US state of Deleware.
Background music is a concert recording of a 17th century battle piece "L'homme Arme" (the armed man), arranged for consort of viols and lute, and performed by the Boston based El Dorado Ensemble - Its full of martial calls, battle noises, and assorted heroics.
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