Shop Strength Shelves

The simple torsion box, as many times as I had done projects using this time-honored construction method, continues to fascinate me along with many other woodworkers who use it as a lightweight platform of many uses. The first photo below shows a simple shelf that I don't remember how long ago I put it up there - made from particle board - to support some not so heavy items . You can tell the shelf had started to sag in the middle despite a side rail attached to the particle board. 

Next photo are two replacement shelves made with the torsion box construction method. I would have preferred to call them industrial strength shelves for the amount of weight they carry while remaining steadfastly rigid.  Later, below, you will see that each shelf weighs no more than one volume of a dictionary and four magazine issues, which you can carry with one hand.  The particle board shelf weighs six times more.

Side rails and ribs are from 1/2 inch plywood, 1-1/4 inch wide. The "skin" was from 1/4 inch plywood. As in all torsion box constructions, glue and pin nails are all that were used. 

The "skin" is always cut a little over-sized and trimmed later. The quickest way is to use a flush trim router bit mounted on a router table. A hand held router will work just as well.

As a test for its carrying strength the finished shelf carries an anvil and a belt sander with no sign of deflection. Just for dramatic effect to show how lightweight the shelf is, I balanced it with one dictionary and four magazines, shown in next photos.

NOTE: Portable torsion box work bench on two Krenov saw horses.

Those who follow this blog had seen several projects using the exact same construction method - from benches to platform beds and portable work benches, etc. This is a very worthwhile construction method that is easy to learn and get hooked on.