Applying paste wax to the outside of the parts makes it a little easier to remove the excess epoxy that squeezes out. The parts should be pushed up tight to keep the paste wax from getting into the joints.
The deckle parts fit together in a rotating pattern so they have to be assembled in a specific way. First two opposite corners are joined, making identical “L” shapes.
Then those “L”s are joined to form a rectangle. No glue here; these photos just show the sequence.
Epoxy has been applied to both sides of every surface in the joint (see the post “Gluing Moulds”). Then the parts have been fitted together and clamped. These picture frame clamps dig into the wood but they work well, putting pressure right where it’s needed. The edges will be rounded off anyway.
I leave the glue alone until after it hardens. Trying to remove the excess while it’s still soft just smears it all over.
The clamped deckle is set aside for the glue to cure.