If a properly applied dustcover paper wrinkles at times, no worries. That's expansion of the paper's fibers, almost always due to high humidity, and the paper will contract and go flat again when the humidity goes down.
We've had dustcover discussions in the past. In my recollection,
this Grumble thread is one of the best on this topic.
Check out this
YouTube demonstration video made by Anton's in Australia. It's the best demonstration video I've seen for gluing dustcovers. It also demonstrates the best way to join multiple mat layers together.
Any good quality PVA glue used for frame miters can work, but my favorite is ATG Turbo, which has the right viscosity for the purpose, and plenty of solids in the emulsion.
If you have trouble using glue to install dustcovers, you're not doing it right. In classes, I've learned of at least a few ways to screw it up:
1.
Using too much glue. Use the
thinnest bead of glue that you can dispense continuously around the frame, within 1/4" of the outer edge. Any more than a 1/16" wide bead is too much, because it would soak into the paper, which could cause cockling and slippage, and it takes too long to dry.
2.
Letting the glue "set up" (partially dry) before applying the paper. Nope. Apply the dustcover paper
immediately or no more than 30 seconds after the glue. To avoid delay, I suggest having the sheet of dustcover paper ready to apply before gluing. Sometimes the paper's edges will cockle slightly, but after burnishing and drying, the cockles disappear. Yes they will.
3.
Failing to burnish properly.
Immediately after laying the paper on the glue, use a burnishing bone or any other smooth, flat, rigid tool to squish the wet glue toward the outer edges of the frame, just as a snowplow pushes snow off the road. Use enough pressure to flatten the bead of glue and spread it toward the edges, which also tends to pull the sheet flat. If a bit of glue oozes out under the paper, just wipe it off with a damp towel after trimming. It's water-soluble, you know.
4.
Shredding the paper's edges when trimming. I've always used a fresh single-edge razor blade to trim dustcovers and have never experienced this issue. However, if you use a trimming tool, just make sure the blade is fresh. Also, you could wait to trim the paper until after you install the hanging hardware. Two or three minutes of drying should eliminate any soaked-paper shredding.
5.
Sloppy application. Make sure you're applying the glue with
no gaps, and within 1/4" of the edge (1/8" is better). With normal expansion and contraction, gaps in the bead-line could allow the paper to cockle, and if the glue isn't plowed right out to the frame's edges, then the paper's edges could curl.
I've heard framers say dustcover gluing takes too long. Is 30-60 seconds too much time to invest for a better result? With a bit of practice, gluing can be almost as fast as using ATG, which also has to be burnished, of course.
Remember that ATG tape is among the most expensive adhesives in a typical frame shop, and PVA glue is among the cheapest. So, at any typical Shop Labor Rate, an extra 30 to 60 seconds to use glue instead of ATG almost certainly would cost less than using ATG tape.
And then there's the fact that ATG tape tends to fail, especially if not thoroughly burnished, and when it's necessary to remove a dustcover, it leaves a gooey mess to clean off. On the other hand, a glued dustcover and its residue on the frame can be easily removed using a bit of water.
Practice. Practice. Practice.