Instead of gluing your layers together at the end, you mask the back of your material with double sided transfer tape first, then cut through both at the same time. Every piece comes off the laser already carrying its own adhesive, cut to the exact shape of the piece.
Only the top layer needs it
You do not tape everything. On a two layer piece, only the front-most layer gets the tape, because that is the one being attached to something else. The back layer is your base, so leave it alone.
You also do not need to cover the whole sheet. Tape only the area you are actually cutting in, and place your design over that area so every piece lands on it. Melissa keeps the taped area near the edge of the sheet for exactly this reason.
Where this really pays off
In the video Melissa builds a layered snowflake ornament about two inches across, with holes small enough that gluing them would be almost comical. Thin arms, tiny openings, and a gold mirrored top layer that shows every fingerprint. With tape on the back, there is nothing to squeeze out and nothing to wipe off the front.
One practical note from the cut itself: the two layers were different thicknesses, one sixteenth and one eighth of an inch, so they ran as separate jobs with their own settings rather than together.
Assembling the piece
After the cut, peel the remaining liner off the back of the piece to expose the adhesive. On something delicate a fine pointed tool gets the edge started, and tweezers make placing a small piece much easier than fingers do.
Then it is done. No clamping, no drying time, no waiting to see whether it shifted.
That instant bond is the one thing to be careful about. It grabs on contact, so line the piece up before it touches down, because you are not sliding it into place afterward.
What to buy
The tape in the video is double sided 3M 468MP, which lists 200MP adhesive on the backing. It comes in 12 by 12 sheets as well as rolls, and the sheets are easier to work with when you are masking a flat piece of acrylic. Melissa bought hers on Amazon.
It works the same way on wood, plastic sheet and mirrored acrylic, and it is worth keeping on hand for any project where the pieces are too small or too thin to glue cleanly.
Cutting your own blanks to print on? The same idea applies there. See Homework 50.1: How to Create Custom Laser Cut Blanks for UV Printing.
