The student who built our laser has moved on to working on using lasers to turn industrial waste into consumable fuel.
He has built a man sized contraption to hold a 100W tube vertically. He was going to get a bunch of 80/20, but decided to prototype it with plywood just to get a sense of what will work before buying a bunch of metal.
Well… he tried laminating layers of 1/4" plywood, but they would always slip a little here or there while clamped for the glue to dry. So he added some alignment holes to each piece and slid a rod through the alignment holes with wingnut bolts on each side.
This worked so well, that he moved to 1/8" plywood for more consistency (less chance of voids) and more control over pockets and other contours. He no longer plans to do ANYTHING with metal. This all wood assembly is stronger than the metal would be. And the time to construct layers into parts is very minor.
By taking the “brick wall” approach (each layer is offset from the neighbor layers), this method would allow even a basic Glowforge to assemble a full-size executive desk. Or absolutely anything else. The bigger the easier.
I hear tell that some of the new concrete formulas are amazing as well. It would be possible to create some very sturdy and light weight forms to pour something substantial.
There’s a paradox (I learned it as a stage carpenter) that although metal is stronger than wood, the resulting thinner sections can sometimes make it more flexible for the same weight and thus less suitable for heavy loading and vibration. (This can be fixed by more complex design, but who wants to do that.)
I bet you could do even better (with the right assembly fixtures) with a combination of lasered internal structure and conventional skinning (for looks and continuous load transfer). To get the thickness that makes for something really stiff, you separate the outer layers with ribs that are keyed in by finger-joint-style tabs (which also align the outer layers if they’re built up) and then wrap the whole thing in veneer or even paper.
Sounds like a project I’m working on currently. It’s a multilayered skeleton with metal rods used to maintain alignment and prevent shearing. All of it was cut on my laser cutter. I’ll probably upload a little summary when I’ve completed it.
Foam core. I was intending on using some of the cardboard I had saved, but it collapses under weight and the thickness is never consistent.
Foamcore is really consistent throughout, and the foam will melt back under the heat of the laser leaving a little concave indention between the outer walls which is perfect for this particular application.
You’ll understand when I post the rest of the project why it works so well =P
