I've made one small Torsion box in the past and am about to make another.
So I thought I'd ask the experts here.
This one will be 7' x 4'. It will support a hobbiest CNC (OneFinity) with has a footprint of 62" x 45". Weight of the gantry and spoil board, I guess, will be about the 150lbs.
The gantry and spoil board will also sit on an aluminum extrusion frame that is about 3" high.
My plan is to have this Torsion top sit on a cabinet with draws and cabinets, so the top will have support in the central areas below, not just the ends.
I plan on using 3/4" material for the top and bottom, most likely MDF for both.
So two basic questions:
1) I plan on using 3/4" material for the ribs. Is plywood or MDF better. I'm not worried about the cost difference.
2) Is there an internal rib height where the ribs are less likely to bow, i.e. 2", 3" etc.. With the aluminum chassis, that the gantry sits on, I'm thinking a supported Torsion box doesn't need super high ribs.
I also plan to fill the pockets inside the torsion box with some sound deadening material, looking for recommendations for this, or is this overkill?
I've thought about 2" Pink solid foam, regular fiber glass insulation, spray in expanding foam.
I will build an enclosure over the top of the gantry, so I'm trying to get this to where having a CNC spindle working, in the background, isn't an annoying nuisance.
Thanks