To travel to different chunkin' locations, we need to pack the system down onto our trailer. Deploying from the folded up position is challenging and time consuming, taking a day and a half at the 2002 chunk. This year at the 2003 Punkin Chunk, we were done in about 4 hours.

Our regular traveling configuration totals out at 17300 pounds hauled by Roger's friendly diesel truck. Our ballista cannot travel in firing configuration as many trebuchets do. The rope bundles are positioned over the wheels to balance the trailer. We had built the trailer ourselves and this was the first serious trip they went on. Everyone on the team was impressed by how smoothly a 7300 lb ballista cruises down the highway.

The first order of business is to deploy the rope bundles. To do this, we use the winch to drag them to the front of the Scapus. A specially mounted pulley there lets us pull the bundles in any direction we choose. The winch we use is the same one we use for pullback when operating the machine.

Here is an image from earlier in the season showing the pulley. The drawback winch at the tail of the scapus runs under the scapus (over another pulley) and around the nose pulley, and up to the rope bundles. This lets us drag the bundles forward with ease.

Next, a come-along is used on the tail of the bundle assembly to start tipping it upright into position. Once the heavy lower scutula's start swinging down, it becomes very easy for two of us to lift it.

Before we get too carried away, we hook up the winch cable to the top so we can raise it slowly into position. As it tips the final moment over, it goes Kathump. A frightful event if you are standing nearby.

After the bundles plunk in place, we start adding the transverse regulae. This is one of the more time consuming tasks in raw assembly. The longest piece is still quite heavy, and has to be carried and bolted into place.

Deployment Time Lapse Video

MetaCafe Video Service Mista Balista - A Modern, Steel And Compoisite, Full Sized, Anc Video

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.

Additional Pages for Mista Ballista
Mista Ballista	Mista Ballista is _Team Tormentum's_ *Torsion Division* competition catapult.
Mista Ballista : Modiolus and Epizygis	The Modiolus and Epizygis used in Mista Ballista account for a majority of the time spent. The size and detail needed to construct these items in a way that could reliably contain the force of so much rope worried us, and we over engineered them.
Mista Ballista : Rope Bundles	The rope bundles are the main engine of the machine. The framework that holds everything together is about 24 ft long, and 6 feet tall.
Mista Ballista : 2005 Rope bundle Upgrade	At the 2004 chunk the main stanchions for the torsion frames were bent by the impact of the arms. You can see the animation of when this happened on the Mista Ballista Arms page.
Mista Ballista : 2006 Rope Bundle Reconfiguration	In 2005 we broke our fancy fiberglass arms. In 2006 we got the new carbon fiber arms and video taped them in action in the summer at our 2006 History Chunk. This led us to discover how much they bounced around the outer stanchions. We were getting multiple recoils after every shot, sometimes back at least 30 degrees. That was also just with 2000 lbs of pullback, which is much less than we expect to use in competition.
Mista Ballista : Frame	The framework for the Ballista had to be built strong enough to resist the pullback, and to hold up the 2500 pounds we currently estimate of our engine. It must also push it up 16 feet in the air!
Mista Ballista : Arms	Building an arm for a torsion machine this large has been very challenging. A list of our failures in this area might provide some hints on what not to do.
Mista Ballista : Trailer	One of our goals for the 2003 season is to acquire a dedicated trailer for Mista Ballista.
Mista Ballista : Mystery Parts	All winter during 2003 we have been collecting the parts we need to accomplish our 2003 chunk goals. Here are a bunch of pictures of these random parts. Can you guess what they are for?
Mista Ballista : Deployment (This Page)	To travel to different chunkin' locations, we need to pack the system down onto our trailer. Deploying from the folded up position is challenging and time consuming, taking a day and a half at the 2002 chunk. This year at the 2003 Punkin Chunk, we were done in about 4 hours.
Mista Ballista : Torsion	Mista Ballista's engine operates with torsion from twisted rope bundles. One of the biggest challenges of torsion for this machine has been adding the twist. An onager is pretty straight forward in that a large lever and gravity can be used. With our ballista, the direction of twist is sideways, so alternate means of twisting is needed.
Mista Ballista : Hydraulic and Electric Power	Mista Ballista uses hydraulics for lifting the engine to a 45 degree angle for firing, and also for winding the cord bundles. We also like having electricity on hand since Mr. B has a tendency to break, and need on-field repairs. This page describes what we are using to power up the system.
Mista Ballista : Failed Arms	Building an arm for a torsion machine this large has proven to be very challenging. Based on the experiences of our competitors, who also keep breaking arms, we find that we are not alone in this dilemma.