Torsion box tool mount

[rick carpenter]

Hi all, I'm back after many years away. I want to construct a torsion box as a portable tool mount and I'm just trying to think outside the (torsion) box. I got an old junk aluminum extension ladder a long while back that I am considering using as the torsion box 'guts' to make it lighter. I plan on epoxying and screwing plywood to both surfaces. Would this work? The portable standard-built torsion box I have for my chop saw base is so darn heavy.

Rick Carpenter
Huntsville East Texas

[Richard Coers]

A torsion box is as heavy as you make it. Use 1/4" Baltic birch for the skins and internal grid and there is no way it will be heavy. Even read discussions about thin skins on a foam core. A hollow core closet door sure isn't heavy either with the cardboard grid core. I would be really surprised that a junk aluminum extension ladder would be even close to being flat.

[Kevin Jenness]

Skip the ladder. I worked for years on a 4" x 4' x 8' table with 1/4" lauan skins and a core of 5/16" x 4" basswood 4" o.c half-lapped together. If you want to beat on it, tighten up the grid spacing or use a thicker skin; it will still be light enough to move around. A smaller table could be thinner. Mine was skinned with p-lam but didn't have to be. Let in solid blocking for mounting a vice or what have you.

To save time you could stack-laminate 2 or 3 hollow core doors.

[Frank Pratt]

I built some 7' long torsion box shelves out of 1/8" plywood skins & 1" foam insulation. It was incredibly rigid. Using a ladder is going to be more work, make a heavier table, and it probably won't be as flat.

[rick carpenter]

Thanks y'all, I'll heed your advice and build a proper torsion box.