The Thinking Part

For this assignment, I decided to make 5 Memory Boxes.

What is a Memory Box? Something I made up. The basic idea is it is a box you put on the wall next to a space you need to remember something. An example is ones keys by the front door. The box has hooks on the bottom that things can be attached to. When something is attached, a large LED on the top of the box turns on.


Initial sketches for memory box concepts
[ Left: Internals | Right: How It Works ]


  • 5 Jumbo LEDs
  • 10 Brass Screw Hooks
  • Solid Core Wire
  • 5 Key Rings
  • 1 8’ L x 4” W x H 2” Lumber
  • Wood Glue
  • Picture Frame Hooks
  • 5 Battery Button Holders
  • 10 3v Button Batteries


  • Miter Saw
  • Drill Press
  • Hot Glue Gun
  • Soldering Iron
  • C-clamps

The Process of Building

Boxes from Wood

To start, I needed to connect the two halves of wood to make a block that was 4’ long, 4” wide, and 4” tall. Using wood glue, I connected the two halves together. I held them tight with many c-clamps. I let it site for about 6-8 hours.

Wood being glued together. Held with c-clamps.
[ Gluing Wood Together ]

After the glue set, I needed to cut the lumber into cubes. I measured out 6, 4” blocks. I then used the miter saw to cut.

Miter saw with wood ready to cut.
[ Cutting Blocks from Lumber ]
6 cubes cut out of wood.
[ 6 Cut Blocks ]

Next, I needed to make space in the back of the blocks. This space is for the electronics and batteries. I used a forstner bit with the drill press to drill two holes into the back of each block. The holes went 2/3 into the blocks, and overlapped to create a bigger space.

Block of wood in clamp, secured to drill press. Two holes have been drilled.
[ Drilling Blocks ]
Five blocks with holes drilled into them.
[ Finished Drilling ]

I needed to be able to add an LED to the top of the box and two metal hooks to the bottom. To allow the wires to run from the components to the space I made, I drilled into the top and bottom of the box. On top I drilled a single hole in the center. On the bottom I drilled two holes.

Block in clamp sitting on drill press. Holes drilled in.
[ Left: Hook Holes | Right: LED Hole ]

The last thing I need to do to wood was round off the corners and then all the edges. I used the sanding wheel to do this. In attempt to make the angle on the corners the same, I used a jig to position the blocks at the same angle to the sanding wheel.

Jig lined up at an angle to sanding wheel.
[ Jig for Sanding Corners ]

It was time to add the electrical components and wire everything together.

Workstation setup. Includes, toolbox, laptop, iced coffee, soldering station, helping hands, and more.
[ My Setup ]

First, I made my 5 LEDs and 10 hooks. Each box required one LED and two hooks. I soldered solid core wire to the LED legs and to the screw ends of the hooks. I then wrapped the connections for the LEDs.

LEDs and hooks with solid core wire attached and wrapped with electrical tape.
[ Left: LEDs | Right: Hooks ]

I mounted the LED in the top hole of each box. I used hot glue on th inside of the space to hold the LED (I used painters tape to hold the LED in place until the hot glue dried). I then screwed the hooks into the two bottom holes. I added hot glue to this as well, just in case.

LEDs held down with painters tape so hot glue can dry.
[ Hot Glue Drying ]
LED and hooks in box. Held in place with hot glue.
[ LED and Hooks added ]

To allow the boxes to be hung on walls, I added a mount to the back of each box. They came with small nails to use.

5 boxes with wall hooks attached.
[ Wall Hooks ]

To power the boxes, I used two, 3v button batteries for a total of 6v. I soldered a button battery holder into the space, connecting the LEDs and the hooks. The hooks in this case act as switch.

To close the space I made, I found some thing wood on the junk shelf. I cut out rectangles and mounted them to the back of the box. I used one nail in the lower-left corner so I could open the box if I needed to. The backing rotates around the nail/

5 boxes with backings attached.
[ Backs Attached ]

To test it I put it on a wall and put a key ring across the two hooks.

Box in action.
[ Left: Box Off | Right: Box On ]

What I Made

Note saying "Build 4 more" is attached to memory box. The LED goes on.
[ Memory Box In Action ]