In fact it is rather difficult to get papercrete to stick to plywood. There is no problem using it in this application and removing it later. I have peices of plywood that have been used many times. Eventually it warps and delaminates but with the price of new plywood these days it feels good to get a lot of uses out of it.
Follow progress on the new project at http://www.papercretebyjudith.com/blog
More papercrete info at http://squidoo.com/papercretebyjudith
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