Over the years Ive made a whole bunch of book safes. A couple of them I posted on Instructables and can be found here and here. To make the book safes that little more secure, I like to incorporate locks into them. Admittedly, the locks that I have designed in the past are simple and are easily located on the book. Plus, you need to take into consideration that a book after all is only paper, if you really wanted to get into it you could probably just rip it open!
This time I wanted to disguise the lock so you wouldnt know that the book even had one. This way if someone was looking for a secret book, then hopefully a cursory glance wouldnt arouse any suspicions. I also have a petty large library so I can easily hide the book amongst my books.
The lock is a Solenoid Electromagnetic Lock which has a small reed switch and is opened by running a magnet over the switch. This way I can keep the lock mechanism, switch etc inside the book and hidden from view.
There is a slight danger though in making a lock like this though. If the battery goes flat then you are going to have a hell of a time trying to get it open again and would probably have to destroy the book!
I also discovered a new way of gluing all those pages together which is a million times easier than trying to glue every page.
The project is quite simple and anyone with basic woodwork and soldering skills will be able to make one easily.”

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