Torsion Boxes

The purpose of a torsion box (TB) is to have a flat surface for assembling projects. They have recently been used for tables for DIY CNC router machines. These routers are usually made from MDF, plywood and some metals. A CNC machine, to function well MUST have a flat surface upon which the work piece is attached to. A TB is usually chosen to provide this flat surface. There are several ways to construct a TB, including the beer can one mentioned in another post. Most woodworkers on this forum would usually use a TB for furniture assembly; but aside from constructing the TB itself, care must also be taken to keep the TB ridgid. The TB will sag if enough weight is placed at the center of the TB, which means a supporting structure capable of maintaining flatness needs to be added. Depending on the size of the TB, a system of rails and headers is needed to further reinforce the TB. The thinner the TB is, the more it will sag under loadn and will require more supporting structure.