Intro: Custom Thin-walled Wood Boxes
I needed a custom small wood box, but the craft store boxes were expensive, poorly hinged, and not quite the size I wanted. Here is an instructable to knock out boxes that can be stained, painted, or decoupaged to your hearts delight.
Step 1: Materials
Here are the tools and materials needed:
3mm Baltic Birch plywood
1/4" square wood strips
Power chop saw with 60-80 tooth carbide blade
Thin blade razor saw like X-Acto extra fine razor saw
Low tack masking tape like 3M blue tape
Wood glue like Titebond II
stain or paint
Figure out your outside dimensions. Be sure to add the width of a saw cut to the height if you will be sawing off the top to make a lid. Cutting the lid after gluing the box makes everything line up great.
Step 2: Cutting Pieces
I needed 5 sided boxes with reinforced corners. All of the inside corners are mitered at 45 degrees. I found that carefully cutting the pieces on my power chop saw made them uniform sized with nice sharp edges that I could either leave or round off with a little sandpaper. I was making a half dozen boxes so I made sure to plot out my work carefully. Tape with the names 'top' 'front' will help. If you are confused by the cuts below, put tape on each side marked 'cut 1' 'cut 2' to help. DO NOT SAW OFF YOUR FINGERS!
The key to this method is to cut the pieces a little large then use a stop block on the chop saw to get the pieces exactly the right size.
1. Cut the pieces oversized but nice and square. I ripped them on my table saw then sliced them up on the chop saw. Use a really good blade for minimum chipout. Hold each piece tight to the fence and tight to the stop blocks so your cuts are true.
2. Follow the cut diagram in the second photo and make Cut 1 as a 45 degree bevel cut. It is on the oversized stock so just make sure you aren't cutting off too much and cut it as shown in the third photo. All of the pieces get a Cut 1. Keep your fingers out of the way.
3. Cut 2 is also unmeasured. It is at right angles to Cut 1. All of the pieces get a Cut 2.
4. Cut 3 is the first measured cut. It sets the width of the box and goes through the front, top, and back. Set a stop bock as shown in the fourth and fifth picture with a thick square scrap piece and a strong clamp. This will make all three pieces identical width. Cutting a scrap piece first and measuring it will get you very high accuracy.
5. Cut 4 may be the trickiest. It sets the length (front to back) of the box and goes through the left, top, and right. Set the stop block at the length and test on a scrap piece. Cut the final bevel on the top piece and correct sides of the left and right. Don't feel bad, I messed this one up too until I drew up my cut diagram.
6. Cut 5 sets the height of the box. It is a 90 degree cut so move your chop saw back to 90. It goes through the front, back, left, and right. If you are making a 6 sided box, you need to make two 'top's and cut a 45 degree bevel for Cut 5.
7. The box is pretty strong, but I wanted reinforced corners so cut your 1/4" stock so it will fit inside the box. I just cut them with my X-Acto razor saw. Cutting them on the chop saw will just make the cutoff disappear in a blink. You can use triangle profile reinforcement pieces if people will be looking inside and you need reinforcement.
Step 3: Assembly
1. Lay out your box with a strip of blue masking tape holding the top to the sides flat as shown in the photo. The tape acts like a hinge so you can glue and fold, then when the glue dries remove the tape and you have a nice clean corner without glue squeezeout showing.
2. Flip over the assembly and put glue in all the bevel faces. Use the glue sparingly so it doesn't squirt out all over. I like to use a toothpick or acid brush to spread it.
3. Corner by corner fold up the sides and tape them together. spread glue on the reinforcing pieces and put them in. They stayed in place for me when I gave them a firm press, no tape needed.
4. Let it dry completely. Patience!
Step 4: Cut the Lid
I wanted a removable lid so I cut it on the table saw. I set the saw just to cut through the plywood but leave the reinforcements behind then sawed through them with my X-Acto razor saw. You could do the same thing on the chop saw rotating it for each cut.
Step 5: Finish
After a light sanding to remove any glue and small splinters and knock off sharp edges, it is ready for paint or stain or decoupage! We wanted a tiny packing box effect so it was painted with flat acrylic paints.