Modular Plywood Bookcase With Rotatable Boxes!

In this Instructable I show you how to build a geometric plywood bookcase! This design was made with a cube shelf or cube organizer in mind - but this is an updated version that can be personalized on a whim! For lack of a better word, the cubes, can be rotated in 90-degree increments to make different designs on the face of the bookcase and accommodate different size books and knick-knacks that you wish to display. I also added some LED lights to the back of this modular bookcase. So you're ready at the push of a button to highlight whatever mood you're in :)

This modular bookcase is made entirely from plywood - birch plywood for the boxes and walnut veneered plywood for the case. You can make this out of whatever plywood you like. One of the coolest parts of this modular bookcase is that these boxes are made to nest into one another, and the front-facing design is only limited by your imagination. I already have a great design in mind for Christmas!

So if you build it, have fun with it, and make sure to tag me in the build on Instagram. I want to see all of the fun designs you come up with! Enjoy the build!

• 3/4" Walnut Plywood for Case
• 1/2" Baltic Birch Plywood for Boxes
• 1/4" Plywood for Back Panel
• Walnut Hardwood for Edge Banding
• Wood Glue
• Nail Gun and 23 Gauge Nails
• Clamps
• Painters Tape
• Sander and Sand Paper
• Flush Trim Bit and Palm Router
• LED Strip
• Finish of Your Choice

1. Cut down the sheets of baltic birch plywood to manageable pieces.
2. At the table saw, cut the sheets down to their final width.
   • This will be the depth of the boxes.
   • Set the fence once and make all these cuts at once to minimize any mistakes.
3. Set up a crosscut sled with a stop and cut the two even side sections out first.
   • Doing this allowed me to keep the stop locked in place, allowing for less chance of errors.
4. Move the stop and cut out the box bottoms.
5. Trim off the factory edges from the boards. This is shop grade plywood so the factory edge is not the greatest. Now you have four clean and square sides on all panels.

1. Set the table saw blade to 45 degrees.
2. Cut the miters on the inner box pieces.
   • These angles are what allow the boxes to nest as well as create the diamond-shaped shelves.
3. Reset the fence and cut in the second miter.
   • When cutting miters like this, it is a good idea to do a test cut as the angled edges will make your fence measurements shorter than they actually are.
4. Cut the bevels for the long sides of the box.
   • These bevels will meet at the transition between the box side and the inner angled edge.
5. Since the faces of the box interior will be difficult to reach once the boxes are complete, sand the interiors of all these pieces to 220 before assembly.

Because there are 18 boxes, this was done in 3 different steps to help sequence the process.

Assemble the Mitered Inner Wall

1. Glue the joint together using glue and blue tape.
   • Since there are a lot of these boxes to make and I don't have an endless supply of clamps, I used some CA glue and accelerator to hold the joint closed while the wood glue dried.
2. Using a clamping square, hold the joint tight until the CA glue was set and then repeat the process until you have 18 mitered corners.

Assemble the Remaining Three Sides

1. Glue up the remaining 3 sides
   • I used a clamp-it square to hold the joints square during the glue-up.
2. Pin the joint closed with 23 gauge nails while the glue dries.
3. Repeat this process for the 18 boxes.

Attach the Mitered Inner Wall to the Sides

1. Glue up the mitered wall to the other sides
   1. The mitered sections fit in pretty easily, and because the other box side is already square, there was no need for clamps.

Sand all of the outside faces and edges to 220.

I did this part once all the boxes were done so I could assemble them and build the case off the inside dimension. Adding about an eighth of an inch to let the boxes easily slide in and out when changing the design.

1. Cut down the plywood to final width.
2. Cut the miters with a crosscut sled and sneak up to the final length.
3. Add some dominos to the miters.
   • This will help hold the joints together during glue up.
4. Add a quarter-inch rabbet to the rear edge for the back panel.
5. Glue up the case.
   • When I'm gluing up a long miter joint, especially when working with veneer, I like to add some blue tape to the inside of the joint. This just helps to avoid any squeeze out that would need to be cleaned up later on.
   • To help hold the long side panels vertical and square, use clamping squares.
6. With the corners clamped in place, use two strap clamps to hold the joints tight and retain those perfect miters.
7. Remove the tape and attach the back panel with glue and brad nails.
   1. This back panel prevents the case from racking when the boxes are removed and gives the LEDs something to bounce off of.

1. Cut 1/8th" oversized strips of walnut.
   • This is so that you can flush trim them with a palm router once they have been attached.
2. Attach the edge banding.
   • I find it easiest to work my way around the box. Cutting one end, then marking out the angle for each cut as I go around.
3. Add a few strips of blue tape to each section to hold and clamp the edge banding in place.
4. Use a flush trim bit to get the edge banding flush to the box.
   • I use blue painters tape to protect the veneer .
5. Sand the edge band flush.
   • Be careful to sand only until the edge banding is flush so you don't go through the veneer.

6. Drill a half-inch hole to feed the LED strips though.

To finish the bookcase I went with a flat polyurethane. This will protect the plywood without giving it any sheen, which will make the final product look more like natural plywood.

1. To get an even finish (and save hours of work) apply the finish I used an HVLP spray gun.
   1. You can apply the the traditional way as well.
2. Add a coat of wax to both darken the piece and bring out the richness of the walnut veneer.
3. Attach the LED strip to the back of the case.
4. Add the boxes in any design you want!

Enjoy your new bookcase!