Hi, BadBob,
I'm curious why you use 3/4" wood?
I have cut a few puzzles and just used 1/4" Baltic Birch ply.
That seems durable enough.
I looked at Steve Good's site and his puzzle templates were recommended 1/4" also.
Unless, of course, you are talking about brain teaser type puzzles or stand up puzzles like the
animal puzzles that Harvey Byler designs..
God Bless! Spirithorse