One of the best places to hide things is in plain sight right? So what better place to hide stuff than a smoke detector? It's inconspicuous, everyone's got one, and as it turns out, you can fit quite a bit in there. While disassembling a broken smoke detector for parts, I was surprised at how easily I was left with an empty shell that I could take apart and re-assemble with no tools at all. I realized it would be an amazing hiding place!

DISCLAIMER: Do not go without a working smoke detector just so you can hide things inside yours! You'd probably be better off adding a dummy smoke detector to a room that doesn't already have one.

This is my first instructable, so I hope it is as easy to understand as all of the great instructables I've read up to this point, that I am using for guidance. Any feedback or criticism is welcomed, as are upgrades or modifications.

Step 1: Tools and Planning

Smoke detectors come in all shapes and sizes, so it is very unlikely yours will look like mine. You'll have to decide based on what model you're working with, how you will go about storing things inside. Mine ended up being a bowl suspended from the ceiling. I decided to cut a hole in the top so I could twist it from its ceiling mount to access the stash. Having one that swings open may or may not be easier to work with.

Tools: Any variations of cutting tools should work fine. I found the plastic to be extremely soft. A Dremel would have probably been a good idea, but since I don't have one I had to improvise. Besides that, all I needed was some hot glue, and a small screwdriver for prying the plastic tabs apart.

Step 2: Disassembly

The first thing I needed to do was get inside the smoke detector to pull out all the guts. This was easily done by prying the plastic tabs with a small screwdriver. Be careful because they clearly aren't meant to be opened very many times, I broke a few in the process.

After removing the circuit board and the black plastic divider I had 3 parts to work with. The flat spiky piece that attaches to the ceiling mount, the top section with the battery door, and the bottom section that's most visible when the smoke detector is attached to the ceiling.

Step 3: Cover Up the Holes

Because I didn't want anyone to be able to see inside the slots in the plastic, I cut a piece of the black plastic divider and glued it over the slots so anyone who might happen to look up would hopefully just assume the black was darkness.

Step 4: Clean Up the Insides

There were a lot of plastic pieces on the inside that divided the main storage area into smaller compartments. I snipped off these parts so I'd have more space to hold larger items.

Step 5: Cut a Hole and Glue It Together

Since the top part of the smoke detector is the part that attaches to the ceiling, I wanted to keep the connectors in tact. However, this didn't allow easy access to the compartment so I decided to cut a hole. I ended up drilling through the plastic and snipping through what was left. (Again, a Dremel probably would have worked better) Then I filed the edges and glued the top and middle parts together and clipped the bottom on with its plastic tabs.

Step 6: See What Will Fit Inside!

I was surprised at what fit in there. I decided to keep the door working, a few pieces of velcro on a usb drive would allow you to get to it quickly without pulling the whole thing down.

Now I can use this to hide a bag of blue crystals, or a second cell phone from my wife. (Come on, it's way cooler than a ceiling tile)

Step 7: Test It Out!

Nope, doesn't detect smoke anymore.

I was curious as to how much my new secret compartment would hold. So I tested it using a common international measuring unit: the peanut. It measured in at over 1 cup, and it probably could have held a few more.

Other ideas:
Adding an led light to the smoke detector for authenticity.
Removing more of the plastic to fit something larger, without having to slide it under.

Thanks for reading my first instructable, if you liked it please vote for me in the Secret Doors and Compartments contest!