Introduction: $5 DIY | 12v Small LED Bunk or Storage Light

By
About: I'm a Nerd and a garage inventor. My dad used to say, "There he goes...off to 'The Lair' to invent something. Try not to burn the house down, OK?" I am a Graphic Designer & Illustrator from the South. I love…

This is an article describing the process I used to build a couple of wooden LED bunk lights for my friend's houseboat. I designed these myself. I also built and installed them without assistance, so it's an easy project. You will also see photos and video of a black-stained, RGB LED Bunk Light I built for my son's bunk bed at home. This is truly a versatile project.
The "Small LED Bunk Light" is designed to run off of a 12V battery, but you may use any 12V DC source that can handle the power requirement. The battery I use is a standard marine deep cycle 12V battery that I have set aside strictly for the purpose of running this light. It is recharged daily by a small solar charger.
Depending on the type of LED strips you use, this unit will consume only 2 to <7 Watts of power. This light also produces significantly more lumens per Watt than the previous bulbs and fixtures that were installed. Additionally, the "run-time" from the battery is longer and the lighting is visually more pleasing. This has been my experience, yours will vary based on your build & parts list.

—►WHY ARE THESE LIGHTS SO AWESOME? I spent only $5 building each one!

  • These lights are very tough, maintenance-free, inexpensive,and can be made from scrap material - mostly.
  • The build requires a minimum of tools and parts to complete.
  • You get to choose which color LED's you want to use.
  • You can also vary the design of the fixture.
  • You get to make it any size you want and paint it any color you like.
  • Best of all, you can make this with a family member or friend.

—► If you like what I've made and it inspires you then please vote for me and share your project photos!

♦SEE MORE! If you would like to see the larger version of this project which is used as a houseboat cabin light, click HERE.


►DESIGN & BUILD NOTES:

You should be able to build one of these with scrap or inexpensive wood and tools you may already have on-hand. Of course, if you choose to use premium hardwoods then you can expect that the results will be absolutely fantastic. If you don't have a table saw then just use a regular handsaw. As long as the blade makes a cut wide enough to hold your plastic lens you will be fine. My primary investments on this project were the switch and the LED strip lights (just over $4.49).

►WHERE ELSE CAN YOU USE THESE LIGHTS?

Anywhere you have a 12V DC battery or 12V DC Power. This will work great in car trunks, bid-rig truck bunks, boats, R.V.'s, storage areas, work areas, laundry rooms or as general purpose bunk bed lighting. They are great since they are tough and need no maintenance. This lighting unit design gives you the opportunity to redesign it to fit your tastes, needs and budget.
With an A/C adapter as power, I have some of these working well on my son’s bunk bed at home. Two long versions of these lights (with no installed power switch) are also being used as landscape lighting along the fence in my yard where I park my car at night. Their power source is a simple ATX Power Supply located indoors. You can also scavenge sufficiently decent power supplies from set-top entertainment equipment, corporate networking equipment, mini-pc's..etc.

As I mention in a comment below, 120v to 12v adapters will work nicely but they need to be rated high enough to cover the power requirements of your light. Be sure to review the datasheet provided by the LED manufacturer for power requirements per meter.


►WHAT WAS MY NEED FOR THIS LIGHTING?

I designed these for a friend of mine to help him update his house boat with a higher quality bunk bed reading light. It features a high-quality switch as well as 85,000-hour warm white SMD5050 LED strips to nearly eliminate maintenance. Many of the 5W and 10W bayonet light bulbs used in marine lighting (deck lights, bunk bed lights, bathrooms and kitchens..etc.) are cheap --which is good-- but they will drain a battery in just a couple of hours and they also have to be replaced regularly.

...Let’s begin!

Step 1: THE PARTS LIST (What You Will Most Likely Need)

My light fixture on the outside dimensions measured ~ 6" x 16". You can build this to any size, but if you do, keep in mind that your measurements will differ from what is listed below.

►WHAT YOU WILL MOST LIKELY NEED:
  • A board for the back of the fixture (about 16" long, 6" wide, 1/2" or 1" thick) - flooring will do
  • 4 smaller pieces of 1" x 2" for sidewalls (two pieces: 16"L x 1"W x 2"H; two pieces: 6"L x 1"W x 2"H)  - diagram coming soon to simplify explanation
  • 1 Push-Button ON/OFF Switch from RadioShackTM (SPST Push On-Push Off Switch; Model:275-011 | Catalog #: 275-011)
  • Hook-up Wire
  • ~2’ length of Warm White LED Strip Lights (300 LED count, 5050 SMD chips, 12-Volt, NON-Waterproof) --- a 16' roll is $16 on ebay 
  • Plexiglass, acrylic sheeting or a fluorescent lighting lens (scavenged or from home improvement store)
  • Drill& wood cutting bits & screw driving bit
  • 10 screws (8 screws for fixture assembly; 2 for mounting)
  • Stain or paint
  • Wood glue liquid nails, or silicone (optional)
  • Krylon Clear Coat or polyurethane finish (optional, but really nice)
  • Metal ruler or straight-edge
  • Permanent marker
  • Soldering Iron & Solder (very little needed)

Step 2: HOW BIG DOES IT NEED TO BE? - Taking a Measurement

My need was for a small light. It measures approximately 6" x 16".
Measure where you need your bunk/utility light to go and write that measurement down.
This will be used to cut a backing plank to the dimensions you recorded.

Step 3: CUT THE WOOD PIECES TO SIZE: 1 BACKING BOARD, 4 SIDEWALL PIECES

Trim your wooden plank or board to match the measured size. This is the backing board of the fixture and will be the exact size of your light.  I used a piece of flooring that was 1" thick x 6" wide and 16" long (after I squared the sides).

Now we need to prepare some small pieces of wood to use as sidewalls to build up a box-type fixture.
So, cut wood for the four sidewall pieces. I ripped a spare 1x4 in half lengthwise to get 1" wide x 2" thick sticks. 

I then ran these pieces through a tablesaw with the blade raised ¼” to cut a groove near one side for the lens to slide into (see the photo image above). You can see three small pieces of wood with grooves in them--these are my test pieces for setting up the depth and location of the cut which will ultimately hold the plastic lens.

Using a chopsaw, I cut the side pieces to the length needed, making sure the ends were on a 45 degree cut so that the four boards fit together making a rectangle.

►►You should now have:

  • 1 board for the backing panel - (16" long, 6" wide, 1/2" or 1" thick)

  • 4 smaller pieces of 1" x 2" for sidewalls - (two pieces: 16"L x 1"W x 2"H; two pieces: 6"L x 1"W x 2"H)

Together, they will form a box-shaped light fixture. I will try to upload a diagram for these pieces and how they go together soon, but I think it might be obvious from the photos.


Step 4: SAND THE WOOD AND ASSEMBLE THE FIXTURE

Pre-drill holes for your screws in the backing board. Use two per sidewall, but leave one short side alone (no holes).

Assemble the box with three of the sidewalls (1 short side and the 2 long ones) and screw them together. It may be necessary for you to use wood glue or sealant between the joints if this will be used near water or moisture. I used 1.2” brass screws.

At this point, there should be one short sidewall left off.  It will NOT screw into the backing board. It will be attached via two screws that go into the neighboring sidewalls. For my lights, the right side was used as my "removable service access panel". 

Drill two holes (one on each end) in the remaining sidewall.This panel is to be removable so that we can install the fixture and install a lens.

Leave this side off for now. It gets installed only AFTER we mount the fixture and insert the lens.

Step 5: DRILL a HOLE AND INSTALL THE POWER SWITCH

Drill a hole and install the power switch. I used epoxy to secure it and to make it moisture resistant.  The 12v push-button switch goes into a sidewall of the light fixture.  Make sure to install it on one of the three sidewalls already assembled.

⇒Be sure to use a properly rated switch to handle your power requirements!

NOTE: I found it best to solder 6” wire leads onto the two connectors of the push-button switch first, otherwise it’s a tight fit later on when you need to connect the wiring internally. 

Step 6: INSTALL LED STRIPS & APPLY EPOXY TO SECURE IT; SOLDER POWER CONNECTIONS

After cutting two lengths of led strip lighting, remove backing tape and adhere the strips to the inside of the box-like fixture.

Apply epoxy in a few areas to secure. DO NOT cover the power terminal pads on the ends until you have wired it for power.

Using a soldering iron, connect the positive (+) of one strip to the positive (+) of the strip next to it. Do the same for the ground (–) connectors. You should now have two strips connected together on one end ONLY.

Connect one wire from the installed switch to the remaining positive (+) connector pad on the LED strip lighting.

Using a length of wire (~1 foot) connect a wire to the ground (-) of the led strip lighting.

Drill a hole in the light fixture backing board to allow you to run the power wires out to your power source. Run the two remaining wires (+ from switch, ground from LED strip) through the hole and apply silicone sealant.

⇒IMPORTANT SAFETY NOTE: In this photo, I have all wires of one color.  Normally, I use Red for Positive (+) and Black or white for Ground/Negative(-).   DO NOT GET THE ORIENTATION WRONG WHEN YOU CONNECT THE UNIT TO POWER.  ALWAYS DOUBLE CHECK YOUR WORK! See wiring diagram at end of the article for info on how to connect to the primary power supply voltage.

Step 7: POWER TEST | LED Lighting

Temporarily connect the unit to 12v of power to see if the strips light properly.

For this, you can use: a 12v battery, 2x 6v batteries in series, or a 12v adapter for household current

If the unit lights, then proceed. Otherwise, check the wiring.  Always observe proper electrical safety procedures and always use a fuse for direct current devices!

—►VIDEO NOTES: I am attaching some videos for the black RGB Bunk Light I made for underneath my son's raised bunk bed. The videos were recorded while I tested some RGB LED strips with a remote.  I've not installed the lens or polished the wood finish yet, but it's getting there.
     These videos aren't great quality and are provided as-is for further explanation of how you can customize this lighting project to your needs. You can see that you have choices other than white lights. Also noticeable are the stylish grooves on the exterior of the fixture made by a table saw.


 

Step 8: PREPARE & CUT a LENS COVER; PERFORM a TEST FIT

Using a metal ruler and permanent marker, draw a rectangle on the plastic lens sheet.
This lens will need to be precisely cut to fit inside the grooves you made in the fixture. Be sure to measure length and width for the lens from "groove-to-groove" on the fixture.

Cut this out with a plastic cutting tool or a rotary tool with a cut-off disc. If you have a laser cutting system then you'll have a perfect cut, with no burrs or nicks in the plastic/acrylic. Your work time on this task will be significantly less as well.

Slide it into the fixture to test-fit it.  Using a torch or gas flame, carefully and only quickly, heat the edges to remove any sharp pieces. As the heat hits the plastic, the sharp edges will melt a little and become dull.  Do not keep the flame in one place, always keep it moving. This step is optional.

Step 9: PAINT/STAIN & SEAL THE FIXTURE

Remove the lens first.

I put a bevel on the walls of my light fixture to make it look nicer and to be more kid-friendly. You can do this with a sander or some sandpaper.

Paint and seal the fixture to your liking.Do not apply paint to the led strips or electrical connectors. Those parts may be sealed with rubber compound or crystal clear epoxy for safety and to prevent moisture damage.

Step 10: Install the Lighting Fixture; Install Lens Cover & Sidewall

This light is designed to be connected as mentioned here:

12v Battery (+)  →  FUSE →  FIXTURE (+)
12v Battery (-) →→→→→→→ FIXTURE (-)
 
Or
 
12v Battery (+)  -→ FUSE → LED PWM Dimming Unit → FIXTURE (+)
12v Battery (-) →→→→→→  LED PWM Dimming Unit → FIXTURE (-)

►A picture with a wiring diagram is included. Please ask for help if you have questions.
 
Find a suitable spot to attach or secure the fixture. I screwed mine directly to studs above each bunk bed. Screws can be used inside the fixture, just be sure to avoid any area with the LED strips.

Connect power leads to those coming in from your source battery (SEE ABOVE DIAGRAM or INCLUDED WIRING DIAGRAM PHOTO). Use solder to secure the connections or you can use wire nuts and electrical tape. I prefer to solder all of my connections and wrap generously with 3M vinyl tape. Now push the slack from the connected lead wires through the hole in the fixture and back into the wall.

Install the lens cover, by sliding the plastic or acrylic sheet into the grooves.

Screw on the sidewall panel.

Enjoy!

Thanks for your time and please share your photos if you attempt to make a bunk light!


BUILD NOTES: A laser cutting system would help this project a great deal. I could have executed a much more creative design and could have used premium metal, stone or wooden materials. A 3D printer would also allow something more fascinating than a simple "box-type" fixture as well. This is a great, durable little light for very little investment. I'm quite satisfied with the way it turned out.   If you have access to any of these other resources, don't forget to feature awesome engravings of various vector art, text or pattern designs on the sides or lens.  You could also have simple text labels, warning info, power ratings..etc engraved.