Framing a 3000 piece jigsaw

[fineedge]

puzzle on a board - second board same size on top of puzzle - Masking tape to hold the two boards together - flip over - remove tape bits - remove what was the bottom board - sticky board ( I make my own with something I get called ME Glue - paint board with roller and glue - allow to dry to sticky surface and walla -) never had a failure BUT have experienced failures with spray glue - in time it just loses it's tackiness and the puzzle slips ie when a mount was used - no problem when close framed which many customers prefer.
Once had a puzzle of Neuschwanstein that was about a metre high and 1.8m long -old puzzle -thick pieces so I just rolled it up like a carpet to turn it over.

[stcstc]

I would just use double sided mount film from hotpress

its sticks solid to almost anything i have tried

and it aint coming off