Mount a Poster on Plywood

Here's a quick, easy and inexpensive way of mounting a poster in a permanent and clean-looking way. I bought this poster as a contrast to my 3D periodic table, and wanted to do Murray Robertson's great artwork justice as opposed to just pinning it to the wall. There are other descriptions of how to make plywood-backed posters, but the poster I got was thick and glossy and I was concerned that the mod podge approach might not be best suited to the my poster. So I used spray-on contact adhesive instead, and it worked well enough that I thought I'd share the process.

- poster. Make sure the poster is nice and flat. I left mine between two sheets of plywood overnight.
- spray adhesive. I used Super 77, but I assume any contact cement spray adhesive would work.
- plywood. Thicker and higher quality the better, for planarity and edge appearance, respectively. Cut to the size of the poster or slightly larger.
- a large sheet of paper. I stuck two pieces of brown butcher paper together with masking tape. The paper needs to be bigger than the poster.
- finish for the edges. I used Varathane water-soluble crystal clear finish.

Spray the back of the poster and the good face of the plywood with the adhesive. Leave to dry for 10 minutes. It should be barely tacky. This is important: you want the poster and the plywood to stick to each other, but not to the paper.

Now: gently lay the paper on the plywood so it covers all but an inch or so of the plywood. Line the poster up and stick it down on the edge, ensuring there are no bumps or wrinkles. You have precious little leeway for misalignment with contact adhesive, but the paper helps enormously in getting it lined up properly. I did mine for the first time by myself and while trying to get photos, and it still came out great. Just take care to not apply pressure to the paper!

Move the paper, and stick down more of the poster. I used a cloth to press it down. Keep going until all of the poster is down.

I trimmed the plywood, poster and all, on the table saw. I did it straight after gluing and it didn't affect the edge at all. If you don't have a table saw, a circular saw is fine BUT make sure the poster is face down when you cut. Use a guide (a piece of wood clamped to the plywood). I sanded the edges by hand with 150 and 220 grit sandpaper and sealed them with two coats of clear finish, sanding between coats.

Final product looks good enough that even though this was my first try I'll be happy to hang it in my office.