Floating Box Shelf

This floating box shelf makes for a fun and relatively easy project. The dimensions shown in the attached blueprint can be modified to make various sizes which can look really dynamic when all nested together on your wall. I've included a blueprint showing the dimensions of the box I made.

While I have access to and used a table saw, dado stack, and drill press to make this shelf, I have previously made these same shelves using a circular saw, router with dado bit, and a handheld drill/driver.

Supplies

• 1 2'x4' sheet of 1/2" plywood (I used a birch plywood from Home Depot)
• 1 piece of 1/4" plywood for the back of the shelf (dimensions will vary depending on the size and quantity of shelves you choose to make
• 3/4" sheet of MDF approximately 24" long and 3" wide
• Wood glue
• 2 heavy duty anchors. Choose anchors that will hold at least 40 pounds
• 3/4" nails for nail gun
• Wood filler
• Your choice of paint

Step 1: Cut Sides and Top/Bottom

Begin by cutting your side, top, and bottom pieces to width and length from the 2'x4' sheet of 1/2" plywood. You can do this on a table saw or with a circular saw.

Step 2: Cut Rabbets

Next layout the rabbets. You'll want to cut the rabbets into your SIDE pieces. Depending on your particular sheet of plywood you may need to adjust your dimensions slightly. The sheet I used was almost a perfect half inch thick so my rabbets are 1/4" deep and 1/2" wide.

There are a few ways you can cut rabbets. You can use a dado blade as I show in the picture, you can use a regular table saw blade using this two step technique, or you can use a hand router with a rabbet bit.

Step 3: Cut Dado for Back Panel

This is the secret to the floating shelf look. You'll cut a 1/4" deep by 1/4" wide (or however thick the plywood is that you use for the back) dado along one face of the top, bottom, and side pieces.

The dado should be inset 3/4" from the edge of the board to leave room for the cleat that will be used to hang the shelf to the wall.

Step 4: Cut Back Panel

From the 1/4" piece of plywood cut out the back panel. Getting the dimensions on this just right is very important. If the back panel is too big, the top, bottom, and sides won't come together tightly. If you cut it too small then you'll have a gap showing. The way to figure out how big this panel should be is to measure how big the opening of the box will be when it is assembled and then add 2x the depth of the dado you cut in the back and sides. To be on the safe side you'll then subtract 1/16" from the length and width.

For example, if my opening is 17" by 7" and the dados I cut were 1/4" deep then my back panel would be 17.5" by 7.5". Again, to be safe I took off 1/16" from the length and width so that the panel isn't too big.

Step 5: Cut the French Cleat

To hang the shelf on the wall you'll use a French cleat. This cleat is made of two parts. One part is secured to the wall (see the picture) and the other part is secured to shelf (see pictures).

I made my cleat from a 3/4" piece of a MDF. This cleat doesn't need to be the same length as the shelf. My cleat pieces are each about 12" long.

I set my table saw to 45° and then cut a length so that the narrower of the two faces was 1" wide. See the blueprint for dimensions.

With one long piece of cleat I went to my chop saw and cut the cleat into two pieces.

Step 6: Sand Box Sides

Before you assemble the box you'll want to sand—at the very least—the inside faces. It will be very difficult to sand these faces later so make sure to do it BEFORE assembly.

Step 7: Assemble the Box

Start the assembly by placing the back panel into the dado of the two long sides (the top and bottom in my case). If you're careful you can get the sides to stand up as seen in the picture. Next you'll apply glue to the rabbets of each side piece and then put the box together.

Depending on what you plan on putting in/on this shelf it is a good idea to use a brad nailer to secure the sides as well. Once I had the box together I held each top/side corner together tightly while I added a few nails being careful to make sure that I was shooting straight so as not to have a nail come out the top/bottom.

With the box assembled you can adde the cleat to the back. Center the cleat on the back along the top edge, mark the two edges so that you know where to apply glue, and then after you have applied glue place the cleat in place so that the long face is towards with the cleat pointing towards the bottom of the shelf.

Step 8: Drill the Holes in the Wall Cleat

It is critical that this step is done correctly otherwise you won't be able to secure this half of the cleat to the wall.

On the wider of the two faces of the cleat (the face opposite of the angle cut). Measure in from each end 2" and mark a line. On that same face, measure 1/2" up from the bottom of the cleat (the bottom of the cleat is the edge opposite of the angled edge). These marks will give you the location of where to drill holes.

You'll first drill one hole at each location that is large enough in diameter to fit the anchor screw heads into. This hole needs to be about 3/8" deep. Don't drill it too deep as you need enough thickness remaining for the piece to maintain its strength. I used a brad point bit for this so that when I go to drill the next hole it is easy to find the center.

Next, change drill bits to one that is just larger than the diameter of the anchor screw threads. Carefully drill down into the existing hole making sure to center the bit and then drill completely through. Do this for each hole.

Step 9: Finish the Shelf

Using wood filler, smooth out the front edges and joints of the box. Once the wood filler is dry carefully sand the edges and the top/sides of the box.

As you can see in the finished picture you can get creative with your painting. I like to finish some of my boxes with a clear coat on the inside faces of the box to add some depth.You can also paint all of the outside and inside faces.

Step 10: Hang the Shelf

Drill holes for the anchors, use a hammer or mallet to carefully drive them into the wall, and then secure your cleat to the wall. The angled edge of the cleat should point up.

Once the paint is dry and your wall cleat is ready you can enjoy your new shelf!

If you liked this project, you can find more inspiration and ideas on Instagram @mighty_maker.