Step 1: Put your books in order.
Stack your books in the order you want them to be in.

Open the top book and take a look at the front endpaper. This sheet of extra thick paper is glued to the cover (on the left side) and the front of the pages (on the right) and it holds the book together.

You need the top book's endpaper to re-assemble the book box after you've cut out the cavity, so it must be kept in good condition.

In most books, you have one regular page glued to the endpaper, known as the "first sheet". This page is NOT necessary, and will get in the way later, so if your top book has one (and most books do, and some books have more than one) you'll start by...

Step 2: Cut off the top book's first sheet, if it's glued to the endpaper.
Use scissors and remove the first sheet. If multiple pages are glued to the endpaper, cut them all off.

You don't have to be super neat about this; you just want to get rid of this page so it's not in the way when you finish the book box.

Step 3: Separate pages from covers with plastic sheets or plastic wrap.
You're gluing the outside of the pages, but you don't want to glue them to the covers yet. I use flexible translucent plastic sheets to protect the covers, but you can also use plastic wrap.

For the top book, place one sheet of plastic between the front endpaper and the rest of the pages. (This protects the front endpaper so it won't get glued down.) Then place another sheet between the last page and the back cover.

For all other books, place one plastic sheet between the first page and the top cover, and a second plastic sheet between the last page and the back cover.

Step 4: Paint all the page edges with glue.
Take a book and brush glue around the page edges. This should be a thin but complete layer.

Make sure to run the brush up against the plastic dividers, so the glue goes all the way to the top and bottom edges of every book.

Repeat this process for all other books in the stack.

Step 5: Weigh the books down and let them dry.
Re-stack your books with the top book open and the cover (with attached endpaper) folded out of the way. Place a flat, sturdy slab on the top book.

Since I'm using acrylic plates, and the glue won't stick to them, I can remove the top plastic divider; if your top slab might stick to glue, leave the top plastic in place.

Place a heavy weight on the top slab, something 40 pounds or heavier. Make sure the individual books are squared and straight: twisted or tilted books will ruin your box.

Leave your setup to dry. I like to give it 24 hours, but you may need more or less time depending on temperature and humidity. It's always better to err on the side of a longer drying time; taking the weight off too early can allow the pages to warp.

Step 6: Remove the books from the setup.
Take the weight off and remove the top slab and the plastic dividers. If you're using plastic sheets, or plan on re-using your plastic wrap, now's a good time to clean them a bit by peeling off the bigger blobs of dried glue.

Step 7: Trim dried glue off the edges.
In every book, run a blade along the edges of the pages to trim off any protruding dried glue. You don't want this extra glue showing when you assemble the book box.

I use a box cutter for this, as I can get a better grip, and the wider blade makes it easier to hold parallel against the pages, so I don't cut into the paper by accident.

Step 8: Glue the covers to the pages.
Be careful here, because you do NOT want to glue the top book's front cover and the bottom book's back cover, since those covers have to be folded out of the way later.

(In these photographs, I've put plastic sheets in the books to show what should not be glued; this is just for instructional purposes and it's not necessary for you to do the same.)

Start on the bottom book. Paint a thin layer of glue on the top of the pages, around the edge. Close the top cover onto the glue. The bottom book's back cover is not glued.

For all middle books, paint glue around the edges on the top AND bottom of the pages, then close both covers. The middle books' covers are all glued down.

For the top book, paint glue around the edges on the bottom of the pages, then close the back cover onto the glue. The top book's front cover and front endsheet are not glued.

Step 9: Glue the books into a stack.
Now that every book is glued together, it's time to glue the books into a stack.

Take the bottom book, paint a thin layer of glue around the top edge, and then place the next book on top of it.

Keep gluing the books, one on top of the other, finishing with the top book.

Make sure the stack is straight and square on all sides! A crooked stack will ruin the box.

Step 10: Weigh the books down and let them dry again.
Place your top slab back onto the stack, then put a heavy weight onto the slab. Wipe away any glue leaking out from between the books.

Leave it alone for another 24 hours.

Here's the result when it's dried: a brick of books with everything glued together except the back cover, the front cover, and the front endpaper.

Step 11: Cut through the bottom book's back endpaper.
After the stack has dried, open up the back cover, take an X-Acto knife, and carefully slice the endpaper between the page block and the back cover. You want to cut the endpaper ONLY, and not the cover behind it.

In cheaper books, this is the only cut you'll need to make, but higher-quality books often have layers of materials and glue attaching the cover spine to the pages. You will need to cut through this, very slowly and carefully, to peel away the cover from the spine without cutting the cover itself.

The finished cut with the back cover peeled away.

Step 12: Cut the front book between the endpaper and the pages.
This step is difficult: cutting the front cover free WITHOUT cutting the front endpaper.

Figure out the best angle to insert the X-Acto blade between the front endpaper and the page block. Work slowly and carefully, slicing down the entire length of the book without nicking the endpaper.

As with the last step, if the cover's spine is still attached to the pages, it must be carefully cut away.

Success! Now the back cover and top cover (with the front endpaper attached to it) can be folded out of the way for sawing.

Step 13: Mark out the cavity.
Measure and draw a rectangle where the cavity will be. The walls should be an inch thick on all sides.

Step 14: Cut the cavity top with a box cutter.
Take a ruler and a box cutter and cut out the rectangle you've just drawn.

Start and end cuts about 1/4 of an inch outside of the rectangle to make sure the paper is cut all the way through at the corners. Press hard and keep the blade straight down: an angled cut will mess you up later.

The red highlights show where the cuts should be.

Step 15: Remove all the paper that's completely cut out.
Peel out all the paper that's been cut free. This may be only a dozen or so sheets. Any paper still attached to the book can stay where it is.

Why do this first cut by hand, when you're taking the stack over to the scroll saw next? Well, it's notoriously hard to cut straight on a scroll saw. The rectangle you've just cut out will be a guide that's easier to follow than drawn lines.

Step 16: Drill a pilot hole through the book stack.
Flip the front cover, front endpaper, and back cover to the side. If you don't have a drill press, lay the stack on a scrap piece of wood. Plan to drill the hole inside the cavity, near the edge of the rectangle but not touching it.

Put something stiff on top of the stack (a thick piece of scrap chipboard, colored yellow, is shown in the photo) and press it down HARD with your free hand while drilling. This pressure will keep the paper from bunching up around the drill bit, which makes the pages bulge out in both directions, separating the books.

Step 17: Set up your scroll saw.
Thread the blade through the pilot hole and load it into the saw. (See the Supplies page for tips on scroll saw blades and where to get good ones.) Adjust the saw's hold-down clamp to apply a bit of pressure: you want to keep the book stack from jumping up and down during sawing, but you also want to be able to move it around easily.

Note to experienced scroll saw-ers: you can skim the following instructions, as they're mostly for scroll saw neophytes. You probably know how to turn a corner.

Step 18: Saw out of the pilot hole and into the first side.
Turn the saw on. Gently push the book stack against the blade to cut towards the outside edge.

Because you are cutting a thick stack of difficult materials, this will be a VERY slow process. Let the saw set the pace, even if that's just a millimeter at time.

When the blade gets about 1/4 inch from the wall, start turning the stack so that the cut gradually curves around to run along the first side. Because the blade is large, you can't make very tight curves (forcing the blade to turn too sharply will break it) so give yourself space to make the turn.

Step 19: Saw down the first side.
Start cutting the first side of the cavity. Follow the walls of the rectangle you made with the box cutter.

Keep the cut straight by keeping the side of the blade exactly at the edge of the rectangle! (See the photo on the left.)

Move the book stack in whatever way is necessary to keep the blade aligned at the inside of the rectangle. This way, the blade will complete the cut that the box cutter started, and leave a perfectly smooth cavity wall in its wake.

Step 20: Make the first corner.
Saw straight until the blade touches first corner, then back up (keeping the saw running at all times) and saw a new path around the corner, heading into the next side. You'll come back and finish that corner later.

Step 21: Saw the rest of the sides.
Repeat Steps 19 and 20 around the rest of the stack, sawing straight down the sides and working around the corners. If any pages on the top come loose in the process of sawing, go ahead and remove them.

Once you arrive back at the first cut, the inside of the stack will be cut free.

Step 22: Remove the cut pages and cover pieces.
Turn off the saw, pull out the cut pages and cover pieces from the cavity, and shop vac away the extra dust. You now have a rough cavity, but it needs cleaning up.

Step 23: Cut out the corners.
Turn the book stack around and saw off those hanging corners. Once again, keep the side of the blade exactly at the edge of the box cutter-made rectangle.

You'll know you've finished cutting the corner when the hanging bits fly off like confetti.

Step 24: "Sand" off any bumps or irregularities.
Look straight down at the sides and compare the scroll saw cut with the box cutter cut. This makes it easy to see any areas that are rough or uneven.

In this photo, you can see the bump from where the sawing started on the side. This bump needs to be "sanded" off.

Your scroll saw now doubles as a sander. Turn the saw back on and gently run the bumps or rough patches against the blade to grind them off. As with cutting, getting good at this takes practice.

Step 25: Take the book stack off the saw and clean up.
All done with sawing! Take out the blade, remove your cut book stack, and take a shop vac to your work space. Then it's time to head back to the glue.

Step 26: Glue the back cover.
Paint the back of the bottom book with a thin, even layer of glue, and then press the back cover down, re-assembling the bottom book. Then, flip the stack over so you can glue the inside.

Step 27: Paint glue over the inside of the cavity.
Take your time on this step. Paint glue around the sides of the cavity and over the entire bottom. Run the brush over all surfaces multiple times to make sure the entire inside is evenly coated. The wedge brush is good for working extra glue out of the corners and bottom edges.

The glue should be a solid coat, but not so thick that it runs down the sides or pools at the bottom.

Step 28: Weigh it down again and let it dry.
Put the top slab onto the book and weigh it down again. (Once again, if the glue might stick to the top slab, put a layer of plastic underneath it.)

Check on it after 15 minutes or so, to make sure there aren't any glue drips or unsightly bubbles. If it looks good, let it dry for another 24 hours.

Step 29: Trim the inside glue.
After the inside glue has dried, take the weight and the top slab off.

Use a blade to trim protruding dry glue off the inside of the cavity, just like you did when you trimmed the outside of the pages.

Step 30: Glue down the front endpaper.
Brush a thin layer of glue around the top of the book stack.

Lay the endpaper down, lining it up at the edges. Press it down and smooth it out by hand.

Step 31: Weigh it down for the last drying session.
Put the top slab and the weight back onto the book stack for one last 24 hour period.

Step 32: Cut out the top endpaper.
Since the sides and corners of the cavity are hidden under the endpaper, you have to explore a bit to find the first side.

Insert a blade near a corner, and then carefully slide it towards the edge. Once you've found a side of the cavity, run the blade along that side until it stops in the corner.

Now that you've found a corner, you can start there to cut out the next side. Repeat this process around the cavity.

Clean up the edges and corners with an X-Acto knife, if necessary. Do a final inspection to make sure the entire book box looks good.

And you're done! Nice, isn't it?