I agree some examples, sketches, and photos of what you wish to fabricate would be helpful.
A heat gun, clamps, and a rig may get you angled bends (
including 90 degrees, acute angles and gentle curves). You can them lap these bends and try though-bolts or perhaps experiment with rivets (
standard and or aviation style).
There is an amazing selection of plastic automotive panel fasteners out there which could be easier to use than rivets.
I have used a soldering iron to poke holes in coroplast (
and heavy fabrics) before, beats trying to drill small holes.
I once use a combination of automotive fasteners and aluminum washers to secure segments of a hovercraft skirt. Such a combination beats messing with tiny nuts and bolts with dabs locktight. Just depends on how secure you need it to be and if there is redundancy or a back up system such as tape or glue.
http://ecomodder.com/forum/showthrea...ing-14528.html
The model was glued with plastic model glue and maybe some "SealAll", and is now coming apart years later - was always delicate.