Multi-Color LED Fog Spreader




Introduction: Multi-Color LED Fog Spreader

This Instructable is my entry into the Halloween contest. If you like it, please remember to vote.

Fog machines are common equipment when it comes to Halloween, but they have their drawbacks. They shoot fog in only one stream, and the fog is limited to the color white. Now you will be armed with knowledge about how to create a fog spreader that has colors which you can change with the flip of a switch.

Step 1: Materials

For this you will need:

  • Fog machine.
  • 2 sections of PVC pipe.
  • PVC T fitting that fits your pipe
  • 12 bright red LED's
  • 12 bright blue LED's
  • 1 SPST (single pole, single throw) switch
  • 1 SPDT (single pole, double throw) switch
  • Soldering supplies
  • Wire (several yards)
  • Hot glue and hot glue gun
  • Drill with 1/2 in bit and 5 mm (or close) bit.
  • Epoxy
  • Cable ties
  • X-acto knife
  • Tape measure
  • Piece of scrap wood
  • Some sort of strong tape (Foil tape is recommended. This stuff is amazing)

The best place to find cheap LED's is on eBay. You can get 100 from China for under $10, including shipping.

Step 2: Prepare Pipe

First, remove the nozzle cap from the fog machine. If it does not come off, you will have to epoxy the finished rig to the fog machine once building is complete.

Epoxy the nozzle cap to the base of the T connector and allow to dry. (hint: use 5 min epoxy. it saves time)

Insert the 2 segments of pipe into the unused portions of the T piece. I didn't glue these but you may need to.

Use foil tape (or duct tape) to cover the ends of the pipes so the fog does not escape where we don't want it to.

Step 3: Drilling the Pipe

Start with everything on one side of the T, then move to the other and repeat.

First measure the total length of the pipe. Depending on how long of a pipe you have, the distance between holes and number of holes will vary. I used 3 holes on each side with about 8 inches between each, and a 2 inch offset form the end of the pipe and the T connector. Don't make too many holes because the fog will not spread out as it should. Generally 3 is a good number per side.

Mark the holes and drill them. But remember; measure twice, cut once.

Once the holes are drilled you may have excess plastic around the hole. I believe this is caused by my drill having low power so your results may be different. Use a X-acto knife to remove the excess plastic and make the hole clean.

If, like me, you used a spade drill bit, when drilling the hole was completed, the bit punctured the back side of your pipe, cover that hole with foil tape to prevent fog from escaping.

Step 4: Prepare LED's

For this step, do it once of the blue LED's and repeat it for the red LED's.

Mark and drill two 5 mm holes in the piece of scrap wood. The holes should be about 2 inches apart. This will be used as a LED soldering jig.

Take half of your LED's and separate them from the other half of the LED's. On the first half, bend the negative lead of the LED down to the right. This group of LED's will be called the "positives, because the positive lead is sticking up. For the other group, bend the positive lead down to the left. This group of LED's will be called "negatives," because the negative lead is sticking up.

Place a "positive" in the hole on the left side of your jig and a "negative" in the right hole on the jig.
Solder the bent leads to each other and repeat for the rest of the LED's.


Step 5: Attaching the LED's

Again, this step will need to be repeated for each color of LED. This step may seem inefficient, but I decided to add the second color after the first was complete. If you wish to do this differently, go for it, and let me know how it works.

Cut your wire so the positive and negative wires are staggered like in the first picture. Make sure that you have enough wire so the LED's will sit with one on either side of the hole in the pipe.

The pairs of LED's will be wired in parallel. Solder the two positive wires to the positive lead of the two LED's. Then solder the two negative wires to the negative lead of the LED's.

Tape the completed LED assemblies to the pipe on top of the holes in the pipe. Make sure the LED's are pointing outward, in the same direction of the hole. Then do the same for the rest of the LED assemblies.

Once all the LED's have been soldered to the wire and taped to the pipe, hot glue them to the pipe. I only tacked the LED's to the pipe so I can remove and reuse them later if necessary.

When repeating this step for the other set of LED's, tape them to the other side of the pipe.


After repeating, use cable ties to hold the wires in place.

Step 6: Wiring the Switches

First cut off the head of the AC adapter. Strip the wires and test which is positive using a multimeter or other method, usually it will be marked on the wire.

Wire and solder all the electric components according to the diagram. Note that the LED symbol on the diagram means all LED pairs, wired in parallel, of one color.

Regarding the number of LED's you should use, and what specifications your AC adapter will need, see the photo notes in the 3rd picture. If you have any questions about this step, post a comment or PM me, and I will try to reply quickly.

Step 7: Use

Check your wiring for shorts before testing this for the first time.

Once you are sure that your wiring is not faulty, attach the spreader to the nozzle of the fog machine using the piece that was taken from it in Step 2.

Fill your fog machine with fog fluid and plug it in.

Now plug in the AC adapter and flip the on switch. If things went according to plan, one color of LED's should light up. Flip the color selection switch and watch the other color of LED's turn on.

Wait for the fog machine to warm up and make some fog.

Amaze yourself and your friends with your awesome new toy.

Here is a video of it in action.

On Halloween, all the trick-or-treaters loved this. If you did too, please vote.

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    12 years ago on Introduction

    you should have it run through a fog chiller first so that the fog stays low to the ground, which makes for a very cool and creepy effect.
    nice job though.


    Tip 2 years ago

    You need to let a 1-3" gap called a fog gap between the fogger and the pipe. Otherwise, it won't work nearly as well and the fog will turn into liquid in the pipe, making a huge mess.


    11 years ago on Introduction

    This is just for all you folks looking for an easy and low cost solution to driving Led Projects!!

    I found this driver board awhile back and for the cost , I'm giving it a try. I 'm building a lightshow system for my Granddaughter for Christmas and needed a no-programing- required interface to bring it all together.
    What's nice about this device is that it is also programible via serial port and Hypertext terminal if later on she would like to gain direct
    control of her lighting system, so I'm also includeing a
    serial interface (RS 232) card and cable in the package with a programing lesson gift card (with myself as the instructor-lol).

    These two items are availible at the same website for $ 12usd.
    Oh, I almost forgot, this little gem of a driver is only $15 usd+shipping! Both the driver and the serial interface are fully assembiled
    and ready to go.

    To supply the lighting ,I also purchased a 5 meter 5050 smd rgb strip with 300 LEDs (or 60 Leds per meter )waterproof and fully addressable,
    and three 3watt ultra high intensity rgby/w modules, (to be used as wall washers) which are also compatable with these devices and can be
    chained to add as many more as you would like.

    While I'm waiting for this stuff to arrive from China, I'm building housings for all the different effects tI have designed into this system
    I'm reworking 2 ATX computer power supplys to give the system plenty
    of power and they should remain very reliable for years to come.

    Now for the good news! I'm making my first instructibale as I put this project together with lots of pictures and what I hope will be clearly explained narration.
    I'm hoping to finish all the editing and tweeking on that and getting it
    posted before the end of Feb. 2012. If I can borrow a good camcorder from one of my friends, I'll include a video or two
    of the finished project in operation.

    Hope the info about the hardware will help some of you solve your problems with building your Led projects.
    What follows is a link to Sure-Electronics LLc in Nanjing China and tech specs for the driver.

    Good Luck everyone and happy tinkering!!

    Emotec In Texas

    Audio Synchronized RGBW RGB LED Driver Demo Board

    Brief Introduction:

    DE-DD13111 is a LED driver with an audio synchronization mode that virtually
    eliminates the need for real-time software processing for LED lighting effects,
    especially for use with RGBY(W) LED lighting color displays (CD-001-xxx series) , but may also be used to drive LED arrays and LED strips of any length.
    In audio applications,your PC, MP3 player, CD, DVD or cell phone can be used as the audio source. Connected to the driver ,which is
    powered by DC12V, RGBY(W) LED lighting color displays
    will dynamically display the variation of the incoming audio signal.

    The audio input signal is filtered into four kinds of frequency: low, medium,
    medium-high and high, with each range of frequency assigned to a specific PWM driver. Four PWM outputs respectively control one of red, green
    blue and yellow LEDs. You can write commands via Hyper Terminal to
    specify LED color to a corresponding frequency of your choice and adjust the gain of each frequency to change LED intensity. LED intensity can also be
    controlled by duty cycle which is adjusted by the amplitude of the spectrum.
    In addition, either of the two on board jacks can be used for audio signal input or output.

    Definition of frequency:

    Low-- 150HZ
    Medium-- 600HZ
    Medium-high-- 3KHZ
    High-- 6KHZ


    Supply Voltage Input Sensitivity Operating Temperature Humidity Range
    Typ. 12vdc ±0.5vdc -10 to +60 degrees cel. 0-85% RH
    Max. 13.7vdc +75 degrees cel.
    Min. 11.5vdc -40 degrees cel.


    1.Cell Phones
    2.Portable MP3, CD, DVD, AAC players
    3.PC, PDA's


    1. Size: 78.00 (L) ×77.36 (W) ×18.70(H) ±0.2mm
    2. Four PWM outputs control four color LEDs
    3. Accesable via serial port and hypertext terminal to set the corresponding
    relationship of colors and frequency.
    4. Individual PWM gain setting can be configured 4 different ways.
    5. Gain of each of four frequency bands: default 10, adjustable from 1 to 50
    6. Default corresponding relationship of colors and frequency:
    Y/W - low frequency
    B - medium frequency
    G - medium-high frequency
    R - high frequency

    Min. 11.5vdc -40 degrees cel.

    audio driver.jpg

    14 years ago on Introduction

    where can i get cheap leds from china(what website)?


    Reply 14 years ago on Introduction

    I bought mine from eBay. Many sellers there ship from China. Do you plan on trying this project?


    Reply 14 years ago on Introduction

    possibly but right now i am looking for a cheap place to buy leds in bulk. would you mind telling me who the seller is on ebay?


    Reply 13 years ago on Introduction had the best prices on bulk LEDs when I last checked.


    Reply 14 years ago on Introduction

    I'm not really sure on my seller, but just search for LED's on eBay and sort by price lowest first. That should provide a good list with plenty of options for size, number, and color.


    Reply 14 years ago on Introduction

    Millicandelas. It is the brightness unit used for LED's. The higher Mcd the better.


    Reply 14 years ago on Introduction

    Yep, I've found that 5mm is the perfect size for most LED applications.


    Reply 14 years ago on Introduction

    i dont know what mcd to get do you know what yours are?


    Reply 14 years ago on Introduction

    It depends on how much money you want to spend, your application, and how bright you need/want them. Generally, the higher the Mcd, the brighter, and the more expensive.


    Reply 14 years ago on Introduction

    is a 15000mcd Green LED Super Bright good?


    Reply 14 years ago on Introduction

    i am kinda looking for a lower price what do you think the minimum mcd would be


    Reply 14 years ago on Introduction

    It depends on your application. If you need brighter LED's then shell out a little more for the higher Mcd's. If you don't need brightness then 4000-5000 Mcd can work. But again, the higher the Mcd, the brighter.


    Reply 14 years ago on Introduction

    Its often better to compare the power consumption of the leds (mw) as the mcd ratings are often grossly overstated