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!

One of Dave's great finds, the articulated part of a 12 foot long dump truck bed. The base attachment frame, the 12 foot lifting frame, plus a hydraulic cylinder and pump. The cylinder is about 1 foot across, and is very heavy. We plan on assembling the ballista on the 12 foot frame, and using the hydraulics to lift the ballista to a 45 degree angle for firing. We welded extensions to the bottom of the dump frame to improve support around the center of gravity. Best of all, it was very cheap.

Fitting adapters between the regulae and the bottom scutulas of the rope bundles. Here you can see the new adapter plates temporarily bolted in place.

We finished building our regulae frame for holding the rope bundles together. We also fitted brackets for bolting our rope bundles to the frame. Here Kevin and Roger fit the units together. While each metal rope bundle unit weighs in at about 700 pounds, sliding them together proves a bit of a challenge. Getting small bolt holes to line up also requires some finesse. Fortunately, Roger found some Grade 8 bolts which can be persuaded into position without destroying their threads. Nifty.

The regulae frame is then bolted to the transverse regulae, and our scapus climacidos. (The long ladder/runway along which the pumpkin will travel.) To get enough pieces of the proper length, we found a lot of disparate pieces of box and welded them end to end. We also added lots of extra strengtheners not in the original ancient designs for fear of the forces we intend to generate.