8020 Extruded Aluminum as part of build?

[StevenSlaughter]

I've searched a bit, but haven't seen much use of 8020 in foamie builds. My main question, if you don't feel like reading this whole post describing my concept, is:
Can 8020 bond with foam/pmf to create a strong frame with the removable attachment opportunities that 8020 utilizes?

Here is what I'm wondering, and I'd like the opinions of others with more experience...

I still want to build my foamie trailer eventually, but lately, I've been thinking of building a foamie clamshell rooftop tent. I feel like it would be a good project to learn how to build this way, less expensive, and faster to complete and get out camping. We are also moving back into our city house with its 2.5 car garage and 25x30' garden, and I don't have the space to store a whole trailer quite yet. Maybe down the line. I'm thinking of combining a few lightweight materials, including foamie building for the main structure. The design is inspired by the GFC Superlite (gofastcampers.com/pages/superlite). I propose to first build a platform-style roof rack (which I'd like to have anyway for other purposes) on my 2011 Subaru Outback. Something like the Rhino Rack Pioneer Platform is great, but very expensive, so I'm looking at building one out of 8020. Instead of tent material for the three sides when open, I am thinking of sort of origami-fold panels that hinge at the top and flip down to enclose the space or flip out as rain/shade awnings for open air (with mosquito netting) for nice weather. (See my rough model photos.) These could either be foamie construction or 10mm correx. A nice advantage to lightweight but rigid walls is that they can potentially flip out to be awnings without the framing, guy lines, etc. used in tents. So that's the overall idea. Here are the specific questions:

If my roof rack is an 8020 platform, does it make any sense (or is it possible) to build the base of the RTT out of 8020 and foam, wrapped in PMF? The weight would be very evenly spread across the platform, and having the framing made of 8020 means that I could attach the rail of the roof rack and the rail of the tent base to each other using 8020's connectors. This would create the lowest profile, I think and potentially allow the RTT to slide on and off of the rack. If I built the base more traditionally with 2x2 wood framing, then attaching that to the 8020 might require less elegant methods, may not be as strong, and may not be as easily removable. The other thing that could be cool would be that if 8020 framing was used on the top of the RTT shell, it would be easy to create a roofrack on top of that as a nice way to mount, say, a kayak.

Can foam be glued to aluminum? Even if it can, does it make structural or design sense to use 8020 instead of wood to frame the base of the RTT?

[twisted lines]

I have the 80/20 and still consider it a waste to do the rack on top but I might.
Some where I picked up expensive, that would be 80/20
Wood & foam for my next one.

[pchast]

Extruded Aluminum is expensive. I don't understand why you feel its needed for a frame.

Foam has been sucessfully used with other reinforcements; sheet metal forms,
angles, z channels, u forms, thin slices of wood using grain direction, etc.

[RJ Howell]

I'm assuming you're building the RTT as well. The loft in my truck camper is alike to the platform for the RTT. I have steel tube (1.5 x 1.5) E/W with 5/8" plywood over. I believed this was best for support. The foam is sandwiched within the steel frame. The unique part of my build is that overhanging loft, so structural framing was required. Unless you build a cage of sorts to support the RTT separately from the TD (frame up) I figure you'll be doing something along the same lines as I did.

Several folks here have build lift-tops get get that RTT space for standing or sleeping, mine is a bit of both.

.