Assembly Table

[Jerry Bittner]

My assembly table as of now consists of two workbenches bolted together which gives me a top working area of 4 ½ feet long by 42 inches wide.

I would like to extend the length by about another 2 ½ feet and want to have that portion hinged to the existing table with folding legs so that it can hang out of place when not needed – like most everyone my workshop space is at a premium.

Question, do I fabricate the top with a torsion box design using plywood to keep the weight down or should I take the simple route and just use a sheet of melamine or something similar. Concerning the latter, I’m leery that in time it will sag/warp.

If I go the torsion box way and sandwich a couple of pieces of plywood together, what thickness of plywood can I get by with?

[Chris McDowell]

Jerry,
I made mine with a honeycomb of 3/4" ply, with a 1/4" skin glued and nailed to the honeycomb from each silde , and finally a piece of 3/4" mdf screwed down to make a top that is overhanging. This way I can clamp things to the edge and if the top gets too torn up I can just flip it over to the fresh side or eventually replace it when both sides are shot.

[Julio Navarro]

Ive looked into torsion box designs as I am ready to build mine for a top to my work bench.

What I have found is that the two skins can be as thin as 1/2". The important factor is the interior ribs. The spacing and direction as well as how tall or "thick" they are and how strong they are.

I've seen one that has the ribs one solid peice front to back and spacers cut to fit between the long ribs and I have seen other designs with inter locked ribs in a half lap pattern. This seems to be the strongest methods as the ribs, both the north to south and east to west, work together to maintain the top true.

If you position and design the ribs correctly you can use skins as thin as 1/4" although that doesnt make for a good work surface.

The secret is in the inside not the skins.

I plan on using 1/2" mdf for the bottom and probably 1/2" mdf for the top with an interlocking diagonal pattern(honeycomb sorta like) of poplar ribs.