Introduction: Book Light Reading Light
*Thanks to Boing Boing, Make, Craft and all the other sites for featuring this project, and to the Instructables community for voting it as a finalist in the LED contest!
It turns off when its closed and gives off a variable amount of light depending on how far you open it, up to about a 40W light equivalent. It gives a nice warm, soft light and it looks right at home on my bedside table.
Step 1: What You Need
- Basic soldering.
- Basic wood cutting.
- Measure stuff reliably.
- You have to be wiling to scalp a book.
A couple of afternoons, though a lot of that time is waiting for glue and paint to dry.
- Hardback book. At least 1″ thick. (I got mine from the local thrift store.)
- 1/4″ plywood or MDF (About a square foot or so should do it.)
- Wood glue.
- White or clear 2-part epoxy.
- Smoked or sign white acrylic, 1/8″ thick and as big as your book. (I got mine from Tap Plastics.)
- http://www.diodeled.com/products-view.php?id=16(I used this one from SparkFun because its small and sensitive.)
- 2.1mm female panel mount plug. Like this one from Mouser or this one from Jameco.
- 12v 600mA power adapter with a 2.1mm make plug. (Like this one from SparkFun)
- 22 gauge (or so) insulated wire. Stranded or solid core.
- Flexible warm white LED strip. You’ll need enough to be double the width and height of your book. I bought mine by the inch at the local hardware store, (this is what it is, but they only sell wholesale.) If you can’t find it there, these from Phenopix are similar. You can also find other suppliers at this search. You don’t need waterproof, regular watervulnerable is fine.
- White acrylic paint.
- Electrical tape (ideally white)
- Either a) Off-white linen & white glue or b) Ivory or white acrylic paint. Thick, from a tube, not a bottle. This is for simulating the outside pages. Paint is easier to do but it doesn’t feel as nice.
- Craft knife
- Soldering iron and solder.
- Fine grain sand paper (220 or so.)
- Wire cutters.
- Wire strippers.
- 1″ paintbrush.
Step 2: Preparing the Book
Important Note: If you’re here to complain about me desecrating a book, first note that a) it can be easily rebound, and b) book publishers pulp between 30 and 40% of their books unread [another link]. Take it up with them first. At least we’re giving this book a new life and helping out the thrift store.
First we need to scalp the book. Find an appropriate hardcover book. It should be one you won’t weep if you have to re-bind it. It should be at least an inch thick, and have an attractive binding. You can find cheap hardbound books at most thrift stores. I chose City of Light by Lauren Belfer since it was the right size and I the title was irresistible for this project.
Next cut the pages from the book. You should be able to do this by drawing a craft knife once across the binding at the front and once at the back of the book. (If you want to rebind these pages, look here. I don’t want to be accused of scalping books. Again.)
Step 3: Making the Basic Frame
Measure the width, height, and depth of the pages you took out. From 1/4″ plywood (Which is usually only 3/16″ thick. I know!) cut two matching pieces that match the top and bottom of the book, including the slight arc where the binding is. (I actually cut the ends square and sanded the difference.)
Cut the front and back pieces, which should be 3/8″ shorter than the pages are tall. The back piece should have a hole near the bottom for the power plug. The size of the hole depends on the size of your plug.
Use wood glue to attach the basic frame for the book. Use a square to make sure everything is true and clamp until dry. Remove any extra glue with a damp cloth.
After its dry, remove the clamps. Sand the outside and corners smooth. Now we need to make it look like paper again. We can do this one of two ways. The way I prefer is to cover it with cloth that might look a bit like paper. Sackcloth, a cloth flour sack, or other cloth with an ivory color and a noticeable grain is good. You can also use suede or velour if the book is particularly deluxe. (Or even gold leaf if you want!) The other way is to paint it, though I like the feeling of the cloth covering better.
If You Choose Cloth Covering: Cut a strip of cloth as wide as your book is thick, plus an inch or two. (If it’s 1 1/4″ thick, cut a strip 2 1/4″ wide). The length it should go all the way around the edge of the book, plus a couple inches.
Working one side at a time spread a bead of white glue on the inside of the frame and pull the cloth around the outside and fasten it firmly with the glue. You might want to use thumbtacks to help hold it until it dries. Be careful not to get glue on any surface on the outside.
If You Choose Paint: Apply several coats of thick white or ivory acrylic to the outside of the frame, aligning the brush strokes so they go parallel to the cover and simulate the edge of pages. Let dry between coats.
Step 4: The Inner Frame
This is the frame that supports the smoked acrylic. It fits inside our bigger frame and is 1/8″ shorter so the acrylic is flush with the top.
Measure the inside of the frame for the book. In general it should be 3/8″ smaller than the outside frame, since that’s how thick the plywood is. The height of the It should be 1/8″ shorter, since that’s how thick our acrylic is.
Cut the inner frame out of the 1/4″ plywood. Be sure to allow for the hole for the power plug. (I cut mine 3/4″ to allow for the power plug’s fastening nut.) Also be cut notches in the lower right corner for the switch. (My switch is 1/2″ x 1/4″ by 7/16″ high (When closed).
Use wood glue and clamps to glue it in place, leaving the 1/8″ space at the top to hold the acrylic. After the glue is dry apply a coat or two of white paint to the inside to make it a good reflecting box.
Step 5: The Electroincs
Okay, “electronics” is a bit strong. All the hard stuff is already done, we just need to get power to the LEDs and put a switch in there.
Note on LEDs:The LEDs I used stay very cool when on, even in an enclosed pace. Some LED strips, especially ones with super bright LEDs, might get warmer. While the materials used will withstand 300°F (150°C) it is possible that super bright LEDs could get it hotter than that and start a fire. Test your LEDs. Leave them on for an hour. They should be merely warm, not hot to the touch. And play close attention to the book light the first few hours you use it to make sure it's not getting uncomfortably warm. After several hours of use this one was barely above room temperature.
First attach your power plug to the frame. (Especially if it’s like mine and has to be put in from the outside before soldering any wires.)
Now lay out the LED strip the way you want it. The stuff I used you can cut about every 2 inches or every 3 LEDs. The more LEDs you use the more power it will require. With a 600mA power supply you can power at least 3 feet of LEDs. To get nice indirect lighting I fastened mine to the inside of the frame. You could also make a pattern inside the back of the box or something else. I used 30″ (or 45 LEDs) to go around the outside and made roughly the same light as a 40W bulb.
Next run a wire from the power plug to the switch and the LED strip. I used white wire to keep it as bright as possible inside the box, though keeping track of polarity was a pain. I used bits of tape labeled with e polarity to keep them straight. The center connection on the power plug will be positive. Run that to the leftmost pole on the switch and solder it in place. Solder another wire from the rightmost pole on the switch to the + side of the LED strip. (If you use a different switch follow the wiring diagram and choose the pins so the circuit will be on in the default position.)
Solder a final wire from the – side of the LED strip to the outside of the power plug. Plug in the power to make sure everything works. It should turn off when the switch is pressed.
The LEDs should have an adhesive back. Pull the backing off and stick the lights around the inside of the frame. I started at the power plug and went around counter-clockwise.
Step 6: Mounting the Frame
If the back of your book cover isn’t as bright as you want cover it with a piece of paper or card stock. (Or a big piece of sticker paper like I did.)
Fasten the frame in place inside the book cover. I like using a 2-part epoxy for this part for extra durability, but you might be able to get by with a good white glue. Both the back and the spine should be glued to frame. Clamp and wait for the epoxy/glue to cure/dry.
Using epoxy, fasten the switch into place. The body should be flush with the top of the frame so that it will close when the book closes, but the cover should close completely. Clamp until the epoxy dries. (Tip: To keep the epoxy from sticking to the clamp, put a little masking tape on the thing being clamped.)
Cut a small hole in the spine of the cover for the power plug to pass through. (You could also mount the power plug as the colophon, but I didn’t think it matched this book.)
Plug it in and once again be sure that everything works and the power goes off when the cover is closed.
Take a look at where the edge of the frame connects to the cover. If it’s not as smooth as you would like, cut a piece of thick paper or card stock to cover they area and glue it in place with white glue. (Or use sticker paper if you hate messing with glue.)
Step 7: The Acrylic Diffuser
However I’m using a more transparent version. I like the milky appearance and how the light changes depending on how you look at it. It also makes the final light brighter without needing more LEDs. What you use is up to you.
Measure the inside lip of the frame, and note the notch for the switch. Cut the piece yourself or, if you can, get the friendly folks at your local plastic store to cut it for you.
Acrylic is hard to cut smoothly. It’s brittle and likes to chip and crack. If you cut it yourself here are a few tips:
- Use a power tool. Cutting it with a hand saw is more likely to cause pressure at an angle which will cause cracks.
- Go at low speed and go slowly. You do not want to melt the plastic. If it starts melting it will start to bind the blade which will mar the cut. If you think it’s getting close to melting stop for a bit and let everything cool off.
- Tape the top and bottom of the material where you cut. This will prevent chipping.
- Use a blade specific to acrylic. If you can’t get one then use a fine toothed blade.
- If it comes with a paper or plastic covering on both sides, leave it on until you’re ready to glue it in place. It will keep it from scratching.
- It can be helpful to use styrofoam or construction foam under the acrylic to support it shile cutting. Just cut straight though the foam.
- After it’s cut and you’re happy with the fit use a clear or white two-part epoxy to attach the diffuser in place.
Step 8: Use
You're done! Go read a book.
This also works well as a soft light for photography.
Get a patch!
Oh, and if you make one post a photo in the comments! You'll get a patch and my sincere thanks!