Introduction: Simple Key Cabinet Using Old License Plate

About: Hobbyist in woodworking, metalworking and music. Basic knowledge in electronics.

Materials you need:

  • wood board
  • blinker (replace bulbe / LEDs with 3V blinking/flashing LEDs)
  • 3V battery (CD2032)
  • battery holder (for CD2032)
  • flashing LEDs (they have an integrated circuit that makes them blink - maybe this one work: )
  • some wires
  • analog tilt sensor (which we use as on/off switch - I used this one...but if you find any better, I would give it a shot: )
  • some hooks
  • hot glue
  • cableconnector

Machines you need:

  • hot glue gun(I like mine, as it has an adjustable temperature: )
  • battery drill
  • router
  • soldering iron
  • jigsaw

Step 1: Mark Your Pocket and Cut the Outer Border

We start drawing an rectangle on our plank which is 2-3cm smaller than our license plate on each side.

The board needs to be bigger than our license plate - that looks nicer ;)

I decided not tu use rectangular cuttings as buckled outlines makes it look more organic.

Ons side of the board I didnt cut yet, as I wanted to use this area to fix my board to the table using a bar clamp.

Step 2: Routing the Hidden Cabinet

Now the dirty part starts. Better use a dust mask ;)

Routing a layer you should take 5-10mm (0,2-0,4 inch) material away.

Be careful as a router is a really, really dangerous tool!

Use a bar clamp to fix your wood to the table!

Make sure the pocket if big enough for your keys (hold some different in position to check if it fits! My pocket could be a little bit higher...).

Inside the pocket you may wanna drill some mounting holes to mount the key cabinet to the wall.

Don't forget to replace the bulb/LED inside your blinkers with the new ones (our coin cell offers 3V - blinkers usually need 12V - so stock blinkers won't light...).

Step 3: Drill Mounting Holes and Mount Your Hooks

Now we need to drill holes for our blinkers.

As my threats have an outer diameter of 9mm, I decided to drill 8mm holes and try if it works. As it works well in my case there was no need to drill a bigger hole. Start with a smaller diameter as you would need to screw the blinker inside the wood - there's no space for a nut!

Now we need to mount our hooks.
As I didn't have hooks in the right size, I had to saw some screw rings (and file them to unsharpen the corners...).

Plave them in an even distance and mark where to place them.

Step 4: Where to Put the Cables?

Time to use some hot glue:
Place your cables on top of the hooks and use some hot glue to fix it in position.

I prefer using cable connectors between the license plate and our board as it's no big deal and makes everything way easier if I need to modify something later.

Step 5: Mounting the License Plate

It's time to mount our license plate.
Luckily mine has some holes - if yours doesn't just drill some ;)

As we're going to use it as front cover think twice where to mount your hoocs / screw rings. Placing it too low/high might result in annoying gabs below or above our license plate.

I'm using screw rings, which I first bended to an open hook with pliers and a bench vice. After screwing them into the wood I slipped the license plate in and used my pliers to bend the hook into a ring, again. That way the license plate won't slip off accidently.

Use screw rings that are big enough to move your license plate smoothly. Too small rings might result in sticking and bending if you wanna open yout key cabinet...

Step 6: Connecting the Battery and Sensor

Unfortunetly I didn't take any pictures of this while mounting.

I soldered the tilt sensor to one of the battery holder pins (I prefer the positive one - but in this case it soesn't matter which one) and connected the other wire as well.
Then I covered everything in hot glue to avoid any short circuits (you may use heat shrink tubes as well...but as we already hat out hot glue gun ready.. ;).

Then I figured out which direction turns the blinkers on and off and used some more hot glue to attach it to my license plate.