Introduction: Hidden Bookshelf Light Switch
This instuctible will show you how to turn an ordinary hardback book into a hidden switch for a lamp or other corded device.
Last fall, I was looking for a gift for my wife and came across the Secret Passageway Switch at Blight Designs (http://blightdesign.com/misc_book.html). Blight Designs was sold out, but I thought I could make something a bit simpler that didn't have to be screwed to the shelf or run a chain and string through the pages of the book.
This is what I came up with:
Step 1: Gathering Parts and Tools
First, you need to gather materials and tools.
13.5" or so of 1"x1/16" aluminum
1 Lutron lamp dimmer model #TT-300H-BL or equivalent
1 push button switch (I used a Philmore #30-003)
2 small zip ties (not pictured)
Some assorted shrink tube
2"x1"x1/16" adhesive backed neoprene (optional)
Drill with 1/8" and 15/64" bits (or whatever size you need for your zip ties and switch)
Center punch (not vital but it helps to keep the bits from walking in the soft aluminum, a nail and hammer will work too)
Soldering iron and solder
Something to heat the shrink tube (I used a mini torch)
Something to bend the aluminum (a bench vise works well)
Something to cut the aluminum to size (I used a band saw, but a hacksaw or tin snips work too)
Ok. Now we have that out of the way, on to the fun part . . . .
Step 2: Sizing the Book and Marking the Aluminum
First pick the book that you want to use. It should have a loose binding so the aluminum can slide into the spine.
The book I used is 6" deep so I started with a piece of aluminum 13.5" long. The dimensions of the aluminum can be altered to fit the book you intend to use.
Start by making marks at 1.5", 2", 2.5" and 8.5". These marks will be your bend points. The fourth mark should be 2.5" longer than the depth of the book you are using. Since my book was 6" deep, my fourth mark was at 8.5". If your book is 8" deep, your fourth mark will be at 10.5".
Step 3: Bending the Aluminum
After making a couple of these, I built a bend-break to bend the aluminum. You can make the same bends the way I made the first two--by smacking the aluminum with a hammer in the jaws of a vice.
First Bend: It is best to start with the bend at the 1.5" mark first. Clamp the aluminum and bend it over to 90 degrees.
Second Bend: Flip the strip over and clamp it at the 2" mark. Bend the aluminum 90 degrees the opposite direction.
You may have to use a piece of wood to start the bend as shown in the picture above so that you don't collapse the first bend while trying to make the second one.
Third Bend: Flip the aluminum over again and clamp it at the 2.5" mark. This bend is also 90 degrees.
Fourth Bend: As mentioned in Step 3, the location of the fourth and final bend will vary with the depth of your book. This bend is in the same direction as the third bend.
Step 4: Marking and Drilling
So now that the aluminum is bent, it's time to drill some holes for the switch and the strain relief zip ties. The strain relief ties are important, because they will prevent the cord from pulling away from the device over time.
First, you'll need to use a center punch to mark the center between bends one and two.
Next, use a center punch to mark four holes for the strain relief zip ties to go through. I used graph paper to center and square the holes. (It wasn't that accurate, but it did the job. You may want to spend more time laying out these points.)
Time to drill!
First drill the 15/64" hole for the switch between the 1st and 2nd bends.
Then drill the four 1/8" holes for the zip ties.
When you are done it should look something like the last picture in this step.
Step 5: Wires, Soldering, and Shrink Tube
We've come to the part where you ruin a perfectly good lamp dimmer.
Go ahead. Cut that dimmer off the end of the cord.
You can get rid of the dimmer. We are not going to use it.
Now, strip the ends of the wire and solder it onto the switch. Use the center pin and one of the side pins on the switch. It doesn't matter which side pin you use.
Don't forget to slide the shrink tube onto the wire before you solder!
I used three sizes of shrink tube I had laying around. Your selection may vary. What we want to do is provide some electrical separation and strain relief for the wires and terminals.
I used small shrink tube first on each wire, then larger shrink tube to cover the smaller shrink tube and then finally big shrink tube to cover part of the switch and the other layers of shrink tube.
Step 6: Putting It Together
We are getting close to being done!
Put the switch through the hole and secure it with the lock washer and nut.
Feed the zip ties through the holes as shown and tighten them around the cord.
Trim the ends of the zip ties and attach the switch button.
Add the 1/16" neoprene to the bottom furthest away from the switch.
There you go.
Your Secret Bookshelf Light Switch is complete!
On to installation . . . .
Step 7: Installation
Take your selected book and open the front cover. This should open the binding, allowing you to easily slide the flat end of the switch into the spine of the book.
Stand the book up and ensure that the switch depresses when the book is resting and releases when the book is tilted.
Now to your bookshelf . . . .
Pull the books that will surround your new hidden book switch out a few inches. Run the cord behind the books and to an outlet. Slide the books back into place. If the lamp you are using has its own on/off switch, don't forget to leave it in the on position. Connect the cord of your lamp to the cord of your switch, and you are ready.
You can now astound, astonish, or merely confuse your friends and co-workers with your Hidden Bookshelf Light Switch!