I actually just did a glow in the dark puzzle last week. It was a small one so it was fairly easy. I like the suggestion about using fabric, but I actually put mine on construction paper. I imagine you could also use poster board. I put the glue all over the paper, then put the puzzle on top of it. Then I trimmed it to fit. One thing more. sometimes the puzzle will warp while drying. I put mine on a cookie cooling rack with the wet side down and then put a heavy book on top of it. That gives it a flat surface but it still gets air circulation underneath for drying.
By
01/03/2008
Separate it into large pieces, hopefully halves. Slide each piece onto cookie sheet and then put second cookie sheet on top, then flip, then reassemble on table. Apply glue with disposable brush and don't put on too much so it doesn't soak in between pieces. Lay stiff fabric on while glue is wet, allow to dry, install into picture frame, voila'.