Instructables

Hidden Door Latch

I am looking for a secret "latch" to open/close a bookcase that covers a hidden door. There are some nice electromagnet types but they are expensive and need power. Any ideas on a "Chinese puzzle" type of thing where you move a couple of things and it opens? I don't want the classic horror movie things like move a book, lever or statue 'cause that's the first thing someone would try. Just fishing for ideas!

Toga_Dan3 months ago

I dont know how to make it happen, but i liked the use of piano keys in batman. What are the odds that someone would randomly come up with using the same set of keys?

Greenehouse (author) 3 months ago

Thanks Paul for the link and info!

Paul J3 months ago

Try this

http://www.leevalley.com/en/hardware/page.aspx?p=40353&cat=3,41399,41403

dataphool4 years ago
My solution to this problem is:

As you can see in my crude diagram, a magnet separated from the ferrous metal iron pellet so that it is not quite attracted to the magnet.  An approaching  iron mass, a hammer, paper weight, maybe a stapler, will strengthen the magnets pull and cause the lever to pivot causing an action at the other end.

The whole is kept from view by a thin panel.


Hidden Latch.bmp
dagdon5 years ago
My desk has a locking feature with a key for center drawer. when close drawer all the way-- a detent beyond just "closed" -- you can lock center drawer and all other drawers are latched shut (locked too). Because its old and has moved several times, bottom drawer never seemed to open -- it seemed stuck in the closed and locked position. One day I discovered, when all other drawers are closed and latched (center drawer to detent position), then the bottom drawer is operable. It has been my secret compartment ever since that discovery. Just think contrary.
Goodhart6 years ago
There is always the "key and lock" idea too. But instead of your normal looking key (and keyhole) one could form an "ornament" that fits within a hung "decoration" that is actually a lock and keyhole. Or, there is the old standby of a book that is in the bookcase that has been "solidified" internally (pages glued together to make it stronger) to use as a release mechanism....
a lever with a magnetic end would work and maybe a spring to hold the latch tight.
Yes, or one could even use the spring to close the latch and a magnet as a key to open it.
Yes, I think that some of those hidden door that I have seen on tv. You would move a statue or any thing that could hold a magnet over the latch to open it.
Greenehouse (author)  Goodhart6 years ago
Hummm, I like that idea. Maybe I could fashion a key/tool that would go into a keyhole that would push a button to release or lock the mechanism. If it was pushing a lever then I wouldn't need electricity. There might be two holes, one to open and one to close the locks. The simpler the better.
Greenehouse (author)  Goodhart6 years ago
Thanks for the thoughts. My guess is that most anyone would try to tilt, move, turn, etc. anything on a bookshelf to see if it would do anything. Maybe something like a Chinese wooden box puzzle where you need to slide 2 or 3 things in the proper direction and sequence that would then lock or unlock your door.
Yes, like using books scattered about the book shelf, one starting with an E, the next one in sequence being an M, and the last two being books starting with a C all in the proper sequence and each pushed or pulled, whichever is set up to make the puzzle work. This could be accomplished with simple levers, those needed to be pushed, leveraged in one direction, and etc. To solve the sequence thing, each 'activated lever' would also initiate the movement of another "pin" that would either activate the next sequence or cancel out the sequence up to that point, depending on whether the sequence was correct or not. Even a special "lock" with a special key behind the binding (made to open when one know how to) would do.
MaDoGK6 years ago
Is using electricity a problem? Cus if it ain't you could use this. Only problem is hiding your remote...
Greenehouse (author)  MaDoGK6 years ago
Using electricity isn't a problem but I would want a back up plan if the electricity failed. I was thinking I could create a special "pocket" for the remote on the back of a strip of moulding or trim where I could just reach my finger around to hit the open/close button.
caitlinsdad6 years ago
All you have to do is search. Looks like this was done here. Hidden compartment. Good luck.
Greenehouse (author)  caitlinsdad6 years ago
I saw that and liked the thought process. It, however, is a little too obvious that something is there. Thanks for your follow up.
Kiteman6 years ago
It doesn't have to be electromagnetic - hide a strong magnet in the base of a statue, then when you stand it in a certain place it lifts an iron pin out of a slot and allows the bookcase to move.
Greenehouse (author)  Kiteman6 years ago
Good idea. What about the "pin?" Is it best to mount it vertically so gravity let's it drop when released? I would guess the pin has to drop at least 1/4" to be secure enough. Thanks...
I was thinking vertically. Maybe if it's angled on the end (like a door catch) it will lock when you push the shelves back.