Why do you apply Luan on to filon?

You definitely want to laminate the luan to the FRP prior to mounting. That is the only way to ensure you will get a good bond between those materials. If you don't get a good bond, you run the risk of delamination.

Azdel is a great alternative, but you will not get the same rigidity that you would with the luan so you might have to make that up with the mounting structure. It is also quite a bit more expensive.

Make sure you get FRP that is designed for outdoor use.

Judging by what stainless countertops cost (just had some completed) and what camper manufacturers and dealers are charging for a new unit. It' in my estimation that a camper body could be built out of all stainless steel and not mess around with rotting, problematic materials.

what about using these panels as underlayment, a replacement for luan?

The plastic panels at Home Depot/Lowes are pebble finish, fiberglas reinforced polyester. They are waterproof, but I would hesitate on using them on exterior walls since they may not have UV inhibitors in the resin. Also they are not recommended for ceiling panels (I couldn't see a good reason for that).
If you want to use them, add a bit of UV blocker to the resin overcoat to prevent chalking or breaking down in sunlight.

The white, pebble surface, plastic type sheets that I see at Lowes and Home Depot. Is this stuff suitable for the exterior of a camper? UV resistant? Waterproof?

Thanks

There are a lot of composites available; uni-directional based thermoplastic composite ($$$), starboard, etc that I would choose before luan.

The only reasons I can think of to use luan are cost and weight. It is not very durable...

If you are rebuilding look around for something more robust from the marine industry. These Guys carry a lot of materials; Jamestown Distributors

Side note: FRP is fiber reinforced plastic and a version of it in flexible sheets can be bought at many big box hardware stores.
There are many uses for the FRP product.

Thanks. Anyone know of an Azdel and/or a Filon retail seller in the South?

"Robert Weed Plywood is an exclusive distributor of Azdel Composite Panels which are used to replace wood in RV Sidewalls. Made in the USA, Azdel Composite Panels are constructed using a blend of polypropylene and fiberglass, creating an extremely strong and lightweight wall."

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Good luck. Let us know how your re-done nose cone turns out!

*note to self: check out the new 2015 Ford Explorer; they incorporate Azdel paneling technology into the body...

Thanks guys. I am actually rebuilding the nose of my artic fox, and was wondering why you could not put the underlayment on first then just install the filon on top of it? I am looking into azel.