Phone Jack Secret Compartment




Introduction: Phone Jack Secret Compartment

About: There are some things you should just NEVER do.....

Phone Jack Secret Compartment

Hiding behind that mild-mannered phone jack could be a treasure trove kept safe in your own secret compartment.

This instructable will show you how to make a nifty hiding place that slides easily into the wall and pops out with the twist of your wrist.

Super fast to load and super fast to get into!

I thought that a wall box might be a good place to hide things but unscrewing a cover plate was too tedious for me. I don't know why, it just seemed like if I was going to make a secret hiding place it had to have special features or somehow be 'cool'; with just a little bit of James Bond in it (Enter hidden latches!).

I thought about using an electrical outlet but didn't want to have a non-functional outlet and dealing with the electrical wires in the wall seemed a bit too much (doable but not what I wanted to tackle right now), so I settled on the telephone jack.

This design has an enclosed storage space with a flip-top lid. The lid has these little tabs that extend on either side so that the lid stays under the bracket (box) frame, so the lid could not pop up inside the wall and get the storage box caught in the wall.

I always have my little swiss army knife on me so it was a natural to use the nail file on it to actuate the release mechanism.

I thought about where to locate the spring loaded latches (catches); side or top. I ultimately decided on the top and bottom as it seemed easier to fit the mechanism in and 3D printing the vertical slot kept it smoother. I tried three different release mechanisms, one with the top and bottom latches being tied together with cloth so that when the nail file was pressed straight in it would deflect the cloth forward and pull the latches inward. It did not work. Too tight of an angle on the cloth to get the latches to move much. My second attempt was to create fancy semicircular openings in the overlapping latches but it was overly complicated and it would not always actuate both latches. So I settled on the present design where twisting the nail file pulls the latches inward and moving the file up or down makes sure both latches get released, even if not at the same time. It works quite well as evidenced in the video.

Step 1: Materials and Tools


1 - Single-Gang Non-Metallic Low-Voltage Old-Work Bracket

1 - Telephone Wall Jack

2 - 4-40 1/4" Machine Screw

(Or use #4 3/8" sheet metal screws from Home Depot - Watch the sharp points that remain exposed)

2 - Small Compression Spring 0.3 x 0.5" (7.5 x 14mm)*

2 - Medium Compression Spring 0.5 x 0.6" (12.75 x 15.5mm)*

*The springs noted above can be found in this spring assortment.

3D Printed Parts:



Short Latch

Long Latch


Dry Wall Saw

Utility Knife

Glue Gun and Glue Stick

Standard and Phillips Screwdrivers

Sand Paper


Ruler, Level, Lineman Pliers (Not Shown)

Step 2: Print the Box, Lid, and Latches

The 4 printed parts were printed in PLA (200C hot end, 50C build plate).

Attached are .stl files for the following parts.

Main Box (Printed with supports)**

Box Lid

Long Latch

Short Latch (Printed with supports)

**The square indentations for the springs make it a pain to remove the support materials - sorry about that. I have considered making the square spring cutouts go completely through the front of the body, which might aid in clearing out the support material.

Step 3: Assemble Latches

Start by making sure the top and bottom vertical slots are clear of debris. The latches should be able to slide freely with no resistance. Make sure the spring cut outs are also cleaned out. The bottom one is especially hard to remove the support material from.

Install the long latch in the top slot. The angled edge faces the hole in the wall (Away from the phone jack plate - I had posted a section view that had them oriented incorrectly - I have fixed that now). Install the short latch into the bottom slot.

There is a long and short latch because the insertion spot ('neutral position') of the nail file has to be below horizontal. The amount of play of the nail file in the phone jack opening is from horizontal downward. So the 'neutral' starting position is below horizontal and the nail file can be moved up or down from that position.

The small compression springs are inserted with the spring being slipped over the tap in the latch and the bottom of the spring being pushed into the cutout until it is seated.

See the 5 photos taken of one of my yellow preliminary prints that only printed part of the box so that the latches were easy to experiment with and the springs easy to install.

Test the latches by holding the phone jack to the box and inserting the flat bar (swiss army knife nail file) horizontal. Turning the flat vertical should pull in the bottom latch. Then push down on the bar and it should pull in the top latch.

Step 4: Assemble Box

Fit the box lid onto the box and secure it in place with the two 4-40 1/4" machine screws.

There is a tab (possibly strain relief loop) on the terminal block of the phone jack that must be cut away (it gets in the way!). Some additional material needs to be removed in the hole by the spring contact wires. The hole needs to be enlarged slightly so that the flat thin object can turn (i.e., swiss army knife nail file).

Rough up the surface of the back of the phone jack plate. It's nylon so it can be difficult to glue to it. A search of the web seemed to support using hot glue as one of the better choices to glue the box and plate together.

Apply the hot glue and firmly press and hold the box and plate together. Add the medium springs over the plate mounting holes to pop the box out of the wall when it is unlatched.

Add decorative mounting screws by cutting off the heads of the mounting screws and hot gluing them in place.

Step 5: Install Your Phone Jack Mounting Ring (Box)

Test fit the assembled box/plate combination on the low voltage bracket (wall box). You want to make sure the latches work, especially unlatching so that you don't get your box stuck in the wall!

Find a convenient location for your phone jack. You may want to use a stud finder to check on the location of nearby studs so you don't try to install it where it cannot go.

Locate the bracket where you want your phone jack to be and mark its location with a pencil. They have some nice holes in the corners of the bracket to facilitate this. Once you get the corners marked you can connect the dots and have the hole outlined.

Use the drywall saw to cut out the opening. Slide the bracket into the opening and tighten the screws in the corners. This moves the clamps into place and tightens the against the backside of the drywall.

Step 6: Slide the Box Into the Wall

Slide the box into the opening in the bracket. It should slide freely and snap into place with some firm pressure.

Step 7: Unlock the Hiding Place

Unlock the box by inserting a flat, thin object; like a nail file on a swiss army knife; into the phone jack at a slight downward angle. The latches are designed for this size of thin object. You can modify the latches to work with other size objects. (Swiss Army Knife Nail File: ~1mm x 6.4mm x 40mm).

The object (nail file) is inserted and twisted from horizontal to vertical (unlatches the bottom latch), then handle lifted upward (unlatches the top latch). The box should pop out of the wall.

There you have it -- your own secret hiding place where no one would expect.


P.S. The phone jack can actually be used for a phone if you want to wire it up. There is a hole in the bottom rear of the box for the phone cable.

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    Reply 1 year ago



    Question 3 years ago

    Bonjour où peut-on trouver cette prise téléphonique si quelqu'un pourrait me dire je serais intéressé en attente de votre réponse je vous remercie à tous cordialement


    Answer 3 years ago


    4 years ago on Step 7

    A good idea. Better than those fake outlet ones sold on Amazon.

    I'd prefer an fake outlet opened by plugging the metal file into the hot slot, however, as it might give someone who attempts to open up every outlet in the house a good shock :P


    Reply 4 years ago

    I like that idea! Thanks for the suggestion.


    5 years ago

    Nice design, thanks


    5 years ago

    You're a pro! What a great use for 3D printing. The spring loaded clip mechanism is really well done.


    Reply 5 years ago

    Thank you! Very high praise coming from someone with your background.

    It was a challenge to figure something out to discretely actuate the latches. It took 3 different concepts and multiple iterations to get it right. I'm fairly new to 3D printing and have found it a very empowering and creative tool. Nothing quite like having an idea and then holding it in your hand!