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Flashing shoelaces... flexible light pipe material?

Hi. Hallowe'en is approaching, so when I heard about these flashing-LED shoelaces I ordered a pair from Amazon.com to see how they worked, and to possibly incorporate into a door decoration.

The "laces" are some sort of solid clear plastic material, approximately

1/10" in diameter. They are "rubbery" -- there is some stretch if you pull the ends, but it seems limited -- and lack any noticeable odor.

The laces plug into two sides of a small black plastic module containing what I assume is a coin cell and a couple of LEDs. The laces conduct enough light that you can see some effect with only one end plugged in, but with both ends plugged in the laces glow noticeably brighter.

( Which naturally makes one wonder what will happen when one pumps some serious photons through this stuff. )

I like the effect -- there's lots of side-emission, so they're like low-voltage EL wire -- but I want to buy some lengths of the lace material itself and can't find any details on what it is.

Can anyone offer any suggestions on what kind of plastic the laces might be made of? And where one might find this stuff in longer lengths?

Here's the specific product, though there seems to be a lot of it on eBay and Alibaba as well:

and here's a writeup with further details:

Hands-On With The LED Light Up Shoelaces

Any hints or clues will be appreciated.

Frank McKenney

--
  Scientists are people of very dissimilar temperaments doing different 
  things in very different ways.  Among scientists are collectors, 
  classifiers and compulsive tidiers-up; many are detectives by 
  temperament and many are explorers; some are artists and others 
  artisans.  There are poet-scientists and philosopher-scientists and 
  even a few mystics. ... and most people who are in fact scientists 
  could easily have been something else instead. 

                -- Peter Medawar, "Hypothesis and Imagination"
Reply to
Frnak McKenney
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Er, cheap optic fibre?

Reply to
tabbypurr

[...]
[...]

Wonderful suggestion!

I tried exactly those search terms and turned up A Clew: I needed the word "sideglow" (alt: "side-emitting"). A search on:

cheap fiber optic cable solid side glow

turned up all sorts of stuff ranging from $1.50/ft for 1/10-1/8" upwards. I even spotted some 12mm (1/2") cable, bit it was just a _bit_ more expensive.

Nothing in the $0.25/ft range, though. Sigh.

Thanks for getting me moving again.

Frank

--
  "Light thinks it travels faster than anything but it is wrong. 
   No matter how fast light travels, it finds the darkness has 
   always got there first, and is waiting for it." 
                             -- Terry Pratchett
Reply to
Frnak McKenney

If you want cheaper, a fibre optic lamp.

NT

Reply to
tabbypurr

Thanks. I had thought about that, but my impression was that those -- like fiber-optic cable used for data-transfer -- were designed to reduce emission ("losses") from the sides of the cable. Even the unjacketed stuff.

Me, I want to use my "fiber" for illumination and decoration rather than signal transfer. I don't want to minimize side-emissions -- I want them to be as large as possible. Whatever this "lace" material is, it seems to do that fairly well, though I haven't tried lighting it up with a 3W LED yet.

Am I missing something?

Frank

--
  I don?t make jokes.  I just watch the government and report the 
  facts.                     -- Will Rogers
Reply to
Frnak McKenney

Use EL wire. It's the same tech as in ancient backlights but in coax form. Something in the vicinity of 90VAC at 1KHz stimulates an electroluminescent pigment in the inner insulation.

--
I will not see posts from astraweb, theremailer, dizum, or google 
because they host Usenet flooders.
Reply to
Kevin McMurtrie

Hi, Kevin.

I've looked at EL wire before, but it has some limitations:

1) Not so cheap -- roughly $1/ft from Sparkfun 2) Single color 3) Difficult to cut and use in pieces. 4) Requires HV well above what's normally available from micro- controller port pins.

On the other hand, it seems to maintain a consistent, even glow, where "light pipes" tend to be brighter at the (LED) ends.

As far as I can tell, side-emitting "light pipe" doesn't care what light source you use to illuminate it or what color it is.

But thank you for mentioning it. It turns out that one can build one's own EL wire given some Secret Goop (phosphor): twist two pieces of magnet wire together, coat it with SecretGoop, and apply power:

Making EL Wire Step by Step

And I like the _idea_ of EL "tattoos", though I'm not certain I'd want to use one myself:

WTF: These Temporary Tattoos LIGHT UP On Your Skin!

While looking for that I ran across some interesting efforts at making LED-based "glow wire" (be sure to read the comments):

How to Make LED Glow Sticks

Who'd have thought that clear hot-glue sticks can serve as light pipes?

Or clear flexible (fishtank) tubing filled with...

- Salt? - Water with a drop of milk? - Petroluem jelly / Vaseline? - Silicone sealant? - Mineral spirits? - Highlighter ink? - Clear hair gel?

Ahhh. Too many things to try, not enough time. Or, as Hedley Lamarr (Harvey Korman) so succintly put in in "Blazing Saddles":

"My mind is a raging torrent, flooded with rivulets of thought cascading into a waterfall of creative alternatives!"

Barely two weeks before Hallowe'en...

Frank

--
  My father ... drilled into me from an early age that if someone says 
  something is impossible, that just means it will take a bit longer 
  to achieve, and that the only failure in working with equipment is 
  if it fatally electrocutes you. 
                     -- Seth Horowitz / The Universal Sense
Reply to
Frnak McKenney

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