Dude, 'member Webster? Little guy gets adopted by rich parents, and lives in a big old Victorian house, complete with secret passages and an old butler's elevator that he could move around in? I blame those pathways and a lifelong interest in Clue (both the boardgame and the awesome 1985 film adaptation, which my childhood Matt Davish had on Betamax) for a tiny obsession with passageways, hidden doors, and all around Sherlock Holmes-y secret goodness.
So this hidden bookcase door is, you know, crazy amazing.
Trim and finish carpenter Gary Katz walks us through this very impressive build, including a a detailed plan drawing, building the case and the hinge system, and the the trim work.
Even if you never have an opportunity to actually employ one in your home, studying this process will teach you a lot.
Hidden Pivot Bookcase Installation [Gary M. Katz Online]