If you get the Lineco Gummed Hayaku Hinging Tape, practice with it many times before using on customer art.
I recently got some and find it takes a very specific and narrow set of moisture x time parameters to get the adhesive just the right sticky (but not wet), get it on the art, weighted and dried, and maintain a strong adhesive bond. Most times the hinge popped off the art, which never happens when I use hand made starch paste hinges.
I went back to hand made rice starch and mulberry hinges because my first few attempts using the Gummed Hayaku weren't satisfactory.
I'll set time aside to do more experimenting with the Gummed Hayaku, but experimenting with a new product takes away from productive work, which is not what you want right now.
Are you doing these one at a time start to finish?
To speed up production I'd suggest rather than trying to find a quicker to use product, try to set yourself up a little "factory" line to maximize time.
Lay as many of the items out as you can. Apply hinges the way you normally do to each one.
After you have all the hinging done for all the pieces, then move to the next phase. Mounting.
Do all the mounting. Then move to the next phase. Fitting.
Etc.
