Secret passageway switch

[Evelyn Adler]

The classic way to open the hidden entrance to your secret lair behind the shelves in the library: http://blightdesign.com/misc_book.html

When I look at the images, it doesn't seem overly complicated, to build something like that switch. Or is it?

[Armored Rah]

It seems to be a simple pull-cord type switch. I'm sure you could find one at most hardware/electrical stores. While this would work for turning on and off electrical things, it doesn't "feel right" to me. I don't know if it's the overly simplistic design or what, but something just doesn't "click" with me on this. I see no reason why it wouldn't work or why it would be any more complicated than it looks, but I don't think it's the method I would use.

[The Bullet]

You can even have ich waaaay cheaper.
I would use a NC [normally closed] type pushbutton.
This is one where the circuit is closed while the button is NOT pressed.
Install it, put the book on top of it. The book´s weight presses the switch and opens the circuit.
As soon as you lift (or tilt) the book, the circuit becomes closed.

OK, this may not be the mechanical feel that some of you would like.

I would go for another approach:

How about having to pull/lift/tilt say 5 books in the right sequence? This can be done by means of a simple logic circuit.


Best regards

The Bullet

[Mercury Wells]

How much XP would you get for using search spell, detect trap?

[Narsil]

You could make a much more low profile system by using micro-switches or light sensors.

To expand on The Bullet's suggestion you could have an entire row of books, all with sensors or switches and the master switch only operates when you remove the right combination of books. With the right combination of usually open and usually closed switches you could do this without a separate logic circuit, simply by wiring the switches in series (exactly how a logical AND gate works in fact).

Done this way the mechanism would be almost undetectable and you could completely remove or rearrange any or all of the individual books from the shelf without triggering the mechanism.

[Mr. Boltneck]

Unless the aim is to put the switch right on that one spot someone will naturally lean against, thus opening the secret door with amusing results. This appears to be the Hollywood standard method. The technology is simple, but the behavioral engineering has to take a bit of work.

[Will Howard]

You are starting to give me ideas, Evelyn...

[KABAR2]

I had one of these years back when I had a Victorian house...... I had gone to a yard sale
and purchased two greek Icons on painted on wood around 12x16 the other was oil on canvas
on wood around 4ft x 6.5 ft..... it made a perfect door and not too many people wanted to get close
enough to inspect a religious icon..... the locking mechanism was magnetic worked quite well....
and who would expect a gun room behind an icon.........

[Evelyn Adler]

You are starting to give me ideas, Evelyn...

In a good way, I hope!
When I build my secret lair, I will have a very complicated entry system. And death traps. With crocodiles. I like crocodiles!

[KABAR2]

You are starting to give me ideas, Evelyn...

In a good way, I hope!
When I build my secret lair, I will have a very complicated entry system. And death traps. With crocodiles. I like crocodiles!

crocodiles I like them too.... they make great luggage and boots......


crocodiles.... Please include one with a ticking clock in the belly.........

[akumabito]

Well, you can hide all sorts of stuff in hard-cover books.. Maybe a magnetic strip in the spine of a book. And an electromagnetic sensor to control a servo to disengage the lock. It would need a power source, but it could be completely invisible - to open the door, you remove the book, and place it back int he case 'backwards' (spine first).
Problem is, once you do this and enter the room, it's pretty obvious something is off for anyone looking at the book case..

So yeah.. scrap that idea..

Simplest way: a solidified hardcover book directly attached to the door handle.. You can mount these vertically inside the book.. turn the book as you would the door handle and it opens.. Would work with other objects as well, of course.

[Captain Lyerly]

I like the idea of simply attaching some object, whether a book on a shelf (though that has been a little bit over-done), or a sconce, or some bit of trim, to a chain that just lifts a bolt at the back of the bookcase.  By the way, it should swing inward - the tell-tale scuffs and marks on the floor are a dead giveaway if it swings out into the room - and there should be a very easy way of getting out of the secret passageway, perhaps more than one.  Getting stuck in a place nobody even suspects is there would be a nasty way to starve to death.


Cheers!


Chas.

[likeclockworkshop]

If you stick with the magnet idea, you could put a magnet in the book, use a reed switch, when the magnet gets close enough to the switch, it completes a simple circuit which controls a servo connected to a deadbolt, that may be a simple way if you have a nerd friend who works with circuitry. you could springload the book, so once you make the circuit, the book returns to it's original place

[MistressMagpie]

I think you all may be over-thinking this. Use the book to control a pull cord, sure, but skip all the electricity and attach the cord to a latch like this. Simpler, easier, and totally mechanical, so you can still jog down to the lab to pick up the Death Ray when one of your infernal creations knocks out the power line.

[von Corax]

I'm sorry, but I just have to say this before someone else does:

Spoiler (click to show/hide)

Put... ze kendle... BECK!

Now that that's out of the way, I second the proposal to replace the electric switch with some sort of mechanical spring latch, preferably one that makes a good solid "kerchunk" sound when you tilt the book.

[Damnd of Hell]

You can try scavaging a house thermostate for the mercury switch, use this a contact to complete the electrical circuit;  imbed it in a book, then do the usual pull, push, or tilt it complete the circuit.

[MistressMagpie]

I'm sorry, but I just have to say this before someone else does:

Spoiler (click to show/hide)

Put... ze kendle... BECK!

Now that that's out of the way, I second the proposal to replace the electric switch with some sort of mechanical spring latch, preferably one that makes a good solid "kerchunk" sound when you tilt the book.

If the latch on my father's shop door is anything to go by, a latch like I posted makes quite a nice thunk.  It's not the satisfying ker-CLACK! of a knife switch, but it's pretty good.

[VampirateMace]

... and there should be a very easy way of getting out of the secret passageway, perhaps more than one.  Getting stuck in a place nobody even suspects is there would be a nasty way to starve to death.

Or at least keep some water and hardtack in there so that when your friends/relatives eventually realize you missing, you're still alive.

[Otto Von Pifka]

magnetic child safe cabinet latches. cheap, don't rely on electrical power, and can be ripped loose with brute force if something should fail. I used two on the fake aromatic cedar wall in the spare closet. took some work to make them tight enough it won't rattle, but still work. best to have someone on the inside to adjust it and open it if need be.  I put them next to knots in the cedar so I know where to place the release magnets

[Captain Lyerly]

magnetic child safe cabinet latches. cheap, don't rely on electrical power, and can be ripped loose with brute force if something should fail. I used two on the fake aromatic cedar wall in the spare closet. took some work to make them tight enough it won't rattle, but still work. best to have someone on the inside to adjust it and open it if need be.  I put them next to knots in the cedar so I know where to place the release magnets

What a handy excuse!  Here, step into this secret alcove and help me adjust the latch...  Clunk.  "What the heck?"  Which, after a while, leads to:

"For the love of God, Montresor!"  "Yes, for the love of God."  Of course you would want to make sure it was airtight; after a while, the smell...



 


Chas.

[Siliconous Skumins]

If you don't mind a bit of modern tech thrown in there, the easiest way I can think of would be to use a cheap RFID tag and reader hooked up to a small microcontroller (something cheap and easy to use like Arduino / Arduino clone, which can be had for as little as £15). It might sound complicated, but it's REALLY easy to program the chip even if you have NO experience whatsoever. Besides, all the code you need has allready been written, all you have to do is copy and paste the text into the interface software on your computer, then burn it to the chip (will only take you 5 minutes to google the code, copy it, launch the software, hook up the arduino by USB and write it to the chip!).

You could even hide the RFID chip in a personal ring or locket, or even inside one of the book covers. The lock is nothing more complicated than a cheap solenoid that slides a spring-loaded bolt back by electromagnet which is turned on by the arduino. The RFID reader could be hidden behind the wood of the book case, the RFID tag only needs to be 'near' for it to work. Would be totally hidden and impossible to find if you didn't know it was there.

Simples. 

If you do it this way you can use it for all sorts of cool features and tricks too (sound / lighting effects etc). The whole project could be done for around £30 or so.

SS

[Jedediah Solomon]

If you don't mind a bit of modern tech thrown in there, the easiest way I can think of would be to use a cheap RFID tag and reader hooked up to a small microcontroller (something cheap and easy to use like Arduino / Arduino clone, which can be had for as little as £15). It might sound complicated, but it's REALLY easy to program the chip even if you have NO experience whatsoever. Besides, all the code you need has allready been written, all you have to do is copy and paste the text into the interface software on your computer, then burn it to the chip (will only take you 5 minutes to google the code, copy it, launch the software, hook up the arduino by USB and write it to the chip!).

You could even hide the RFID chip in a personal ring or locket, or even inside one of the book covers. The lock is nothing more complicated than a cheap solenoid that slides a spring-loaded bolt back by electromagnet which is turned on by the arduino. The RFID reader could be hidden behind the wood of the book case, the RFID tag only needs to be 'near' for it to work. Would be totally hidden and impossible to find if you didn't know it was there.

Simples. 

If you do it this way you can use it for all sorts of cool features and tricks too (sound / lighting effects etc). The whole project could be done for around £30 or so.

SS

I must add two things here in the interest of safety.
1: keep lots of food in the room, it would make an excellent "Panic Room" (Check out the movie by the same name BTW, with Jodie Foster, Forrest Whitaker and Dwight Yoakum)
2: make it so the power is on when the book/statue/decorative Icon whatever is not moved and the power holds the latch locked against spring tension that would otherwise move the latch to the  open position. when the trigger is operated. or the electricity is interrupted, the spring-loaded latch is released.  That way a power outage actually releases you from your confines.
And a bit of trivia in response to Von Corax's spoiler, ever notice that it is the cutsie (and most of the time blonde) naive young gal that stumbles upon the secret lab of the Mad/Evil/Tyrannical Science type, never the well-trained spy or police?  Don't invite bimbos anywhere near your mansion... they spoil EVERYTHING.   

[akumabito]

And a bit of trivia in response to Von Corax's spoiler, ever notice that it is the cutsie (and most of the time blonde) naive young gal that stumbles upon the secret lab of the Mad/Evil/Tyrannical Science type, never the well-trained spy or police?  Don't invite bimbos anywhere near your mansion... they spoil EVERYTHING.   

But they always find them by accident.. maybe the pro's are just looking too hard, and are too careful for such accidents to happen..

Hmm, I then propose just adding a gigantic red push button right next to your secret entry, clearly labeled in large brightly-colored letters: PUSH TO OPEN SECRET DOOR. The bimbos won't get it, and the people looking for a way in will think it's too obvious (and possibly a trap) and ignore it.. perfect security guaranteed..

[Semonius]

I thought about that already and thought about a cogsystem behind the door powered by a small steamengine to turn the secret door open. I saw this small steamengine on youtube that was powered by a teacandle underneath it. I thought about the key being a teacandle to open the door as the steam turns the cogwheel locking mechanism.. very steampunk. not very immediate but it is very into character,I don't have any schematics to show you what I had in mind but I hope you got the general idea...

and the book idea.. make a metal rod attached to the book and the bolt on the door through the boards of the bookcase.. lift and hinge the book and you lift the rod and you lift the bolt. kinda thing.. I guess it's do-able.. I wouldn't really know how to do it though..   

[Jedediah Solomon]

That would actually be easy if you are able to put a vertical slot in the wall behind the book, fasten the rod securely to the book ( I thought a "fake" book would work best.... leather book cover with  layers of plywood screwed and glued together to the right thickness to be the innards and thus something onto which the lever is fastened) and then on the other side of the wall, a stout chain or a set of cogs operating the latch that releases the door.  Again, make it so that in the event of failure the door can still operate, especially from the inside.  With an alternate release available, feel free to make the mechanism as complex and "Steamy" as you wish