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Help- Thin cheap board/plastic for waterproof poster

  1. Nov 25, 2014 #1
    Hi all-

    I am trying to make a semi-waterproof poster (only needs to be wet for a few hours and not necessary for the poster to last beyond the day)

    I need to back the poster on a hard surface - have tried correx but it wont accept any titebond glue as it is basically treated to be resistant. Have been looking at hardwood today but it is too expensive.

    Any ideas for a thin and CHEAP material that would accept titebond glue and paper???

  2. jcsd
  3. Nov 25, 2014 #2

    Doug Huffman

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    Corrugated plastic has a number of optional additives and surface coatings. The surface coatings can be removed by wiping with acetone or carefully with a flame. Coroplast® is a common building material for aerodynamic human powered vehicles.
  4. Nov 25, 2014 #3
    What I would do is use "scrounged masonite." This would be masonite pulled off the back of an old dresser you find abandoned in an alley. Sometimes they're backed with thin veneer plywood, but that would work just as well. I have two or three sheets of this I keep on hand.

    If your poster is large, and the masonite or plywood thin, you might have to make a 1 x 2 box frame to keep the masonite flat. Anyway, paint it with exterior paint or polyurthethane before mounting the poster to keep it from absorbing too much moisture for the 24 hours you need it. (I assume you suppose it might get rained or snowed on, and not that you're going to immerse it in water.I don't think this would last long totally immersed.)

    If you're not an alley scrounger type, you might look at the free giveaway section on craigslist for a free dresser/bureau.
  5. Nov 25, 2014 #4


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    Maybe check with a local sign shop. When I worked in one, we did our political lawn signs on something that I'm sure we called "aquapel". It was a sort of stiff cardboard poster stock with some kind of wax or plastic coating to make it waterproof. Unfortunately, the only thing that comes up under that entry on Google is a glass treatment. The Coropast that we used had small grooves that corresponded to the internal corrugation. In most instances, that wasn't a problem, but it can be.
    Alternatively, just get a sheet of Bristol board and apply a coat of varnish.
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