by Squigie » Fri Nov 22, 2019 10:48 am
If you intend to 'build a box on a frame', it may be a bit weak.
But if you intend to build a 'monocoque' / 'stressed torsion unit' that people or cargo can be inserted into, it would probably be fine.
It all comes down to design.
There are a lot of good designs around here. Tony Latham's are good examples of putting the strength in 'the box', and what I intend to do.
The frame that I have drawn up for my first build - as yet unnamed, but basically 'Bare Bones and Rough Roads' - would never hold up to much use as a utility trailer, let alone a flat bed. But I intend for the "box" to be a stressed skin design, with elements to increase strength and prevent racking/twisting moments.
The box is the strength.
The frame does offer some strength, but is mostly just the support, and a place to bolt the axle, jacks, and ancillary equipment.
Put another way...
You can build (or buy) a frame and a box; and the trailer and box need their own strength, independently.
But if you build them to be symbiotic, the frame doesn't need anywhere near as much strength.
Think of it like building an airplane fuselage, and then slapping some landing gear on it. The plane doesn't need the landing gear for strength. But the landing gear does need the plane.
I think that makes sense. But my brain isn't running on all cylinders this morning.