Build LED Glow Tubing

I love LED's and am always looking to use them in new ways. Especially for cool effects. I found a great way to couple a blue LED into 1/4 inch tubing. Then by filling the tubing with fluorescent liquid, a glow tube can be created. It took a little experimentation to get right and ended up being very simple. Here is what you will need:

1. Quarter inch clear Tygon tubing (Lowe's or Home depot carries it)
2. Ultra bright blue LEDs (5mm, clear lens, narrow beam i.e. 12-15 degrees)
3. A small plastic squirt bottle similar to a condiment dispensing bottle 
4. a Fluorescent Highlighter (Available at most office supply stores)

Step 1 Preparing the Florescent Dye

The first step is to prepare the dye. Take the back off of the fluorescent highlighter. You can ether pry the ink reservoir out. It is an absorbent cylinder soaked in the dye. My first try at this I pulled it out and used a lot of the dye. I put about a teaspoon into the plastic squeeze bottle. This was way to much. It causes the light to be used quickly and not travel far down the tubing.

What ended up working best and is easiest it to place the end of the highlighter over the mouth of the squeeze bottle and let the water absorb some of the die

Comments

[sinepo]

are these normal led or gree led?

[DJJules]

They are blue LED's. I also tried UV but the blue worked better

Jules

[Attmos]

i love this idea. i used this concept in something i made, thanks for the inspiration. i posted it if you want to take a look.

have fun

[DJJules]

Thanks! I just got a couple ten watt Blue LED emitters that I am hoping to have time to get to for this one on steroids. Check it out here: http://www.dealextreme.com/p/10w-180lm-445-447nm-blue-light-led-emitter-9-11v-100875

Jules

[Oimi]

Is there a better way of securing the batteries so they can be added and removed easier? I would be looking to swing these about for light painting but would be worried the battery would fly out as well.

[DJJules]

If you solder wires to the LED, you can run them back to a battery in your pocket and only sing the tubing part. Also if you use a nine volt battery, you need to add a 200-300 ohm resistor in series.

Have fun!

Jules

[plmqaz1243]

Oops. I didn't read the next page yet.

[plmqaz1243]

Couldn't you use UV Leds?

[jconner3]

ok ill be hounest im lighting up my deadmau5 helmet and i cant figure out the resistor i need to wire 12 white leds too what even portable power sorce i need i need help i have a on off switch 12 white leds and the toobing

[DJJules]

If you are using a white led each one drops about 3.5 volts and you want about 20ma to each so you need a resistor that would be (your supply voltage -3.5) divided by .020 amps. In a nut shell 200-330 ohms for 10-12 volts and about 75-100 ohms for 5-6 volts.

Post a pic when you are finished!

Jules

[jconner3]

soo what battery should i use

[Jack Corsair]

so for the blue color you used what?

[ZeroXL91]

Come to think of it, couldn't you use use EL Wire to illuminate the water? It would be so much brighter!

[Xiero]

If your using UV led's, have you considered using tide detergent? I work on a tech crew and we have these 18" UV cannons that we shine at a wall which we painted with tide. the effects are pretty sweet. The only problems i forsee is coming up with a diluted solution that doesnt creat suds...

[douks]

who can send me The PDF Format of this Project please

[Huntman00]

How long it the tube in the last and second to last pic on step 5????????

[CaseBoy]

how long is the biggest one?

[DJJules]

about 18" but the glow isn't even across the tube, it falls off away from the LED

Jules

[CaseBoy]

so how long can the tube be without the glow dimming?

[scorpenzy]

How do you manage the color, by the LEDs or the hilighter itself? And how do you make a red tube? Last thing, how long can you make the tube while still looking neon?

[DJJules]

The tubes as I built them are using florescent dye that glows yellow/green with blue light exciting the dye. I did try a ultra bright red LED in cloudy water (add a pinch of Corn Starch to a cup of water) and it works. The light intensity falls off as you move away form the LED so it isnt as effective as a neon tube.

[phevtron]

made one which is ''dancing'' to the beats

[kumiko]

This sounds like a great idea in creating the leggings part of this costume:
http://vocaloid.wikia.com/wiki/Piko_Utatane

It might even be possible to attach tubes in a cross shape, but I can't be sure.

Have you tried blue highlighters with blue LEDs?

[ilpug]

could you use the button cell batteries taken from inside AA batteries to power this?

[G-Nugget]

I've been experimenting with these tubes for use around the edge of a clock I'm making with an acrylic face. I am using 3/16" internal diameter tubing and been successful with getting the LEDs a few millimeters into the tube and sealing with silicone.

I found a solution that is a very pale yellow without light but glows very well when lit. The problem that I'm having is that the dye appears to be disappearing. The tubes go from glowing green to eventually being all blue with no fluorescence over a period of usually a couple of days. I noticed that the pictures here show the tubes being mostly blue; is that just the camera? I tried exposing the tubes to UV from a strong black light for days, heating the tubes, and just letting them sit for a while, but the fluorescence only disappears when lit by the LEDs in the ends. I haven't been able to rig something up to expose the tubes to external LEDs. I'm out of ideas for what would cause the dye to decay. Am I doing something wrong or is this normal?

[DJJules]

Mine still are working. What type of Highlighter did you use? I had a challenge coming up with the correct amount of dye. I first squeezed the highlighter liquid into my squirt bottle but it was too strong at first. I am going to go back and try mixing some rubbing alcohol in there to prevent any mildew/mold. fluorescent compounds do not lose their ability to floresce after time.

[G-Nugget]

I'm using a highlighter I had laying around at home. it's just a basic yellow fluorescent highlighter. I have been adjusting the solution and when I first noticed that the tubes were losing the color I added more and it stayed for longer. I'm going to add some more and make another and see if that helps more.

I know it sounds crazy, but the the fluorescence disappears from the ends first, then moves towards the middle. I can't say anything for sure about the mix chemically, but it definitely doesn't fluoresce and doesn't become more concentrated in the areas that still do. The ends are very well sealed and nothing has leaked out. I'm going to take some pictures tonight so what is happening is easier to understand.

[G-Nugget]

pictures: http://s264.photobucket.com/albums/ii173/GNugget0/projects/

Both tubes were made identically and the only difference is that I have had tube 2 lit on the LEDs for about four days and tube 1 for about one day.

[DJJules]

OK, I did a little research and interestingly, the absorption for Fluorescein is close to a Blue LED which is very cool. It is added to bubble levels which make the liquid brighter and show up green. But, it is dissolved in Alcohol when they do that. So, gimmie a couple days and I will try to make a tube that is 50-50 isopropyl alcohol and water.

Jules

[G-Nugget]

I originally tried adding some isopropyl alcohol to the mix, but for a reason that I don't remember, I decided that just water worked better.

[DJJules]

Wow, I wonder if the flourescent material is settling out in the tube? I had one that before I sealed it I touched the end of the highlighter to and it had a distinct difference in glow level. Let me do a little research on this. The stuff that makes it glow is called flourescein check it out here

http://en.wikipedia.org/wiki/Fluorescein

I wonder if the solution is stratifying?

Jules

[ilpug]

best solution: use mineral oil and put in a bit of rubbing alcohol, then add your highlighter stuff and proceed.

[kumiko]

What does the mineral oil and rubbing alcohol do?
Where do you suggest adding the mineral oil, in the alcohol/highlighter/water solution?

[erfror]

If you wrap aluminium foil around the ends (up the size of the LED), and then tape it, you will have a mirror effect at the ends and the light will go more into the tube. Just like gosugenji said.

[Kegtapper]

Several suggestions:
Diluted Mountain Dew in water will create that same effect as the dayglo marker. (its the phosphorus in the soda that causes the glow under blacklight)

Also if you 'frost' the tube it will glow like neon.
-- How to frost the tube?
a fine grain sandpaper (depending on materials surface)
or hold over a cleaning tank that uses freon and rotate it in the vapors

I've experimented with the tubes 10 years ago.


Good Luck

[WRIF101rocks]

I've been trying to make this using hot melt sticks but the light never made it far. These look great and just the color I was looking for! I had one question though. In the pictures it showed a yellow highlighter used for the florescent liquid. When you used blue leds, does it look more yellow than blue in person?

[DJJules]

The yellow highlighter is fluorescent.The blue LED excites the yellow and it looks greenish like a glow stick. Make sure that the highlighter is s fluorescent one. Office Depot etc carries them.

Jules

[gosugenji]

You should tape the ends with the led's so you dont have so much light bleed. Electrical tapes works wonders well for this.

[nh4x4Jeep]

How about the solution that they use for Liquid Cooling CPU's?
They have fluorescent, and UV reactive dyes. They are non-conductive and also have anti-microbial properties.
Just one of ta thousand sites: http://tinyurl.com/2ugtgez

[DJJules]

Yea, there are several things I want to try here. I would love to match the index of refraction of the tubing and have slight amount of non clarity in the solution to scatter the light. I tried this with a super bright RED led and corn starch (just a tiny pinch) it works but the corn starch settles out.