I will not build them as paper card models because the compound curves do not work well in cardboard. One always gets a sharp edge or series of same instead of a smooth curve.
This summer I expect to start one or two by first copying it up to 1/32 scale. Then transfer the pattern to another material, like thin balsa. Or maybe a thick card stock. I do not care for plastic sheet. I like wood better, but this method can be used with any material, Sheet aluminum, brass, copper, whatever.
There are some nice paper card models available in 1/33, like the Catalina PBY 5, WALRUS, SUNDERLAND Mk II, Saunders-Roe S-R.53, Arado 196, BV-138, Do-18D, Aichi E13-A1 Jake, W-2 flying boat USSR and a few others.
Here are a number of dealers of these kits.
I suggest that you compare prices before ordering as some are priced higher than others.
The best glue I found for paper is UHU and you can get that in the tube at Office Depot (not Staples) stores as well as at
http://www.papermodels.net/
http://www.papermodelstore.com/
http://www.paperwarbirds.com/cart/catalogue.php
http://www.strangeplace.com/
These are in Europe:
http://www.e-papermodels.com/catalog/
http://www.gremirmodels.com/
There is a forum of paper card models on line.
Papermodels II
http://groups.google.com/group/Papermodels?hl=en
Be careful with them. They object to copying card models because they claim that it violates copyrights.

There is a person making a model flying boat from an enlarged paper card model of the Dornier DO-15 Wal on the LSP forum. (Large Scale Planes)
http://forum.largescaleplanes.com/index ... =24792&hl=
Anyone on this forum try to build this way?
Stephen