Who can honestly say that they don’t need a trebuchet for home defense? In this episode of Some Assembly Required, Shawn Wasserman designs and builds a trebuchet big enough to throw a pumpkin. Warning - graphic images of exploding fruit.

In this episode of Some Assembly Required, Shawn Wasserman (in for Torben Ruddock) builds a cardboard bridge for temporary use, in this case crossing a kiddy pool of doom. Check to see whether his bridge carries him safely, or whether he takes a plunge.

In this episode of "Some Assembly Required", Torben Ruddock tries 3 propulsion ideas on a home-made hovercraft he built with just plywood, a lawn chair and a shower curtain. It turns out that propulsion is easier than steering. Watch to see what works and the clever steering mechanism.

Torben shows how viewers can publish their own CAD models into the iPad 3D instruction sets shown on Some Assembly Required. CAD formats supported include Autodesk Inventor, Solidworks, Pro/E and most other major CAD packages.

Torben generates a remarkable long-distance blast with this giant air cannon. See how to build your own in this high-energy episode of Some Assembly Required. Visit www.engineering.com/someassemblyrequired for instructions.

Torben builds a squirrel proof bird feeder engineered to thwart a ground assault and make an aerial attack impossible. Visit www.engineering.com/someassemblyrequired for instructions.

Torben builds a hovercraft you can ride using just plywood, a lawn chair and a shower curtain. Power is provided by a leaf blower. You’ll be surprised at how well this works. Visit www.engineering.com/someassemblyrequired for instructions.