Whats the best way to waterproof papier mache without a commercial waterproofing varnish/coat?
There is a fantastic web site in which a UK man did experiments with papier mache and waterproofing over the coarse of a year. Most of the commercial varnish did not hold up. The best outdoor waterproofing, after a year of exposure, was a boat varnish. Sources: http://www.papiermache.co.
