## ASK AN EDUCATOR! “Can EL wire be used as guitar strings?”

Can EL wire be used as guitar strings?

If we look at a cross-section of EL wire you see that is core is made of copper:

According to Dan Ports Electroluminescent Wire paper, the core of his double core wire was ~22 gauge, or 0.64mm. If we look at a comparison of standard steel and nylon guitar string sizes, we can deduce if the tensile strength of the el wire could withstand tuning:

Steel (Regular Light):
E – 0.254mm
B – 0.3302mm
G – 0.4318mm
D – 0.6604mm (wound)
A – 0.9144mm (wound)
E – 1.1684mm (wound)

Acoustic (Light):
E – 0.3048mm
B – 0.5334mm
G – 0.635mm (wound)
D – 0.8128mm (wound)
A – 1.0668mm (wound)
E – 1.3462mm (wound)

Now we need to figure out what the tension exerted on the strings during tuning is. Liutaio Mottola has a great string tension calculator that should get us in the ballpark.

Using Liutaio’s calculator and D’Addario’s string tension guide, it looks like for a steel stringed guitar you will have a max of 19.5 lbs and 7.08 lbs for the nylon acoustic.

Now if we look at the copper, with an approximate UTS of 220 MPa or ~32000 PSI, and use Liutaio’s calculator stating S = UTS * Pi * (D/2)^2, we get a breaking stregth of:

S = 32000PSI * 3.14 * (0.0253in/2)^2
S = ~16.10 lbs

So from our deduction, it looks like you could use EL wire to string an acoustic guitar, and certainly warrants further testing. Some of the hurdles you are going to run into is dealing with the elasticity and spring properties of copper. There is a reason copper is onto used for modern guitar strings. Also, winding on the tuning posts, which could be overcome by soldering the ends to piano wire, and stringing the piano wire through the post. Finally, electronic interference with the pickups. But this shouldn’t be a big problem if you are using a raw acoustic

I am going to try and pick up some as well for my acoustic and give it a try. If the copper can maintain tune, you certainly would have a wicked looking guitar, or at least great show piece!

Alternatively, Dr. Strings has black light active strings which give the same effect with less hackery, but where’s the fun in that?

I hope this answers you question, and good luck with the idea!

Don’t forget, everyone is invited to ask a question!

“Ask an Educator” questions are answered by Adam Kemp, a high school teacher who has been teaching courses in Energy Systems, Systems Engineering, Robotics and Prototyping since 2005.

Filed under: educators — by akemp, posted April 27, 2012 at 1:10 pm

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1. Simple to test — somebody who has a length of EL wire should string it across a soundbox with two bridges, hang a weight on one end, wire it up and twang away.

I’m thinking that problem one would be whether the outer sleeves are tough enough to survive hours of strumming.

If somebody built EL wire with an inner core of coppor over steel instead of pure copper that might help the acoustic properties.

Comment by Mel — April 27, 2012 @ 2:41 pm

2. You will also run into the problem of the phosphor coating breaking apart from vibration, and the thin outer conductor coming into contact with the inner conductor.

The phosphor coating is brittle and becomes even more brittle when it is abused, bent, moved repeatedly. It will most definetly be damaged at the very ends where it is bound to the posts. That is where you will run into continual issues with the two conductors touching from damaged phosphor.

The manufacturer of the wire needs to develop a guitar string type, which has a polymer type phosphor coating that acts more like plastic, rather than crystal.

The EL WIRE needs a re-design for this to work.
I had this idea 2 years ago.

Comment by Tech — April 28, 2012 @ 9:50 am

3. Oh, and also. The double core wire is dual strands of wire twined together, which is then coated with phosphor, and then the thin hair like wire is spiral wound around that.

The image shown IS NOT THE DOUBLE CORE WIRE.

The double core wire is literally two wires in the center instead of one.

So all the above calculations need to be adjusted for that.

El-wire does come in different core sizes also.

But every type will still be a problem in a guitar due to severe vibrations of the delicate crystal phosphor.

Comment by Tech — April 28, 2012 @ 9:57 am

4. Oh and also, if you just BURN the plastic coating with a lighter, about 1/2 inch in from the cut end, you can yank off the plastic nicely, cleanly, no worries about knife splicing, or pulling the fine thin wires.

Years of working with the wire, I learned that having a candle to get the plastic melting hot, then gently, and eaisly, pull the plastic coating off with a pliers, works best.

Comment by Tech — April 28, 2012 @ 10:04 am