Over the years of hobby woodworking I've made the "torsion box design" a specialty favorite when constructing projects that are lightweight, yet extraordinarily rigid and practically unflexing but carry loads multiple times their weight. Copied from how airplane wings are constructed, the torsion box uses thin skins of, say, 1/4 inch oak or walnut veneers, over latticed lightwood ribs to make a top platform. This top will look like a thick slab but is mostly air inside. The two long benches shown below can be carried one handed but each one can seat three adults without flexing. The recent short bench featured in this blog is barely six pounds.
Why the short portable bench? When one reaches a certain age - yours truly a good example - when bending, stooping, squatting are no longer so easily achievable without thinking about a groan-free recovery just for standing up afterwards, a portable short bench, a short stool, is literally an answer from heaven. The short bench is mandatory for us of a certain age when working on anything lower than the strike zone in major league baseball. It will save anyone from invoking the names of minor or major saints, or the classic OMG, just to stand up.
Of course, purchasing one is the easier route but, hey, this is a woodworking blog.
(Below) Finished small bench next to a full size one
Another torsion box bench (below) at the end of our bed
A simple drawing or sketch is good but where possible an actual "life-size" scale is best.
The "ribs" that make up the "innards" can be made from pine (weight consideration).
The glued up "ribs" will soon be cladded with the plywood skin using only glue and pin nails.
The top "skin" below is 3/8 inch oak (shown with finger hold already routed out).
Glue and pin nails complete the clad
The legs are one-inch thick solid oak (tapered on a jig)
Using only glue the legs are clamped together
No hardware of either screws and nails were used. Dowels make sense but I used a through dowel system. The dowels were inserted through from one side as opposed to the true blind dowel assembly. This is the easier method. The pieces are glued together first. Then the holes are drilled through on the joined pieces. There is no chance for mismatched dowel holes which could happen when done the conventional way. This is only possible, of course, when the pieces are narrow enough to make it practical.
Four 3/4 inch dowels will anchor the legs to the top (set). I created a jig to ensure matched holes for the dowels. Shown below the Forstner bit guided by the jig to the legs
Below is the latest gizmo to inhabit the shop. A drill guide that makes any hand drill into a portable bench drill press with more capability. It is an amazing tool, very well made, though pricey. It makes drilling perfectly vertical holes into wide boards that a drill press may not be able to do (when holes are in the middle of the board) and then some.
When not in use, it is easily stored (below) on a small foot print.
Final glue up (below). Fastening the legs to the bottom of the seat
Now, the anguish of working at low level is greatly diminished. And a project boot. So, take care of those joints, your knees, your back.
Why I customized the short bench? I made its dimension so when I sit on it my thighs are parallel with the floor, keeping all joints at near neutral alignment. Does that make sense? You can find out. Try it on commercial benches. If one meets that criteria, buy it. It's a useful, if not healthful, gift to yourself this season.