Converting Violin Bows to Light Sabres


#1

Hi,
I am a Violin and Viola teacher. My students showed me a clip of young violinists playing with ‘Light Sabre’ Bows and being a Star Wars fan it was irresistible to me so I am now planning my Christmas Concert around the Star Wars repertoire with appropriate weaponry, sorry bows. (with a great story about my students escaping a Hutt and battling storm troopers with their bows)
This is the general idea.


The very helpful James has suggested this:
https://littlebirdelectronics.com.au/products/el-wire-coin-cell-mini-inverter connected to EL wire.
I’m wanting to figure out everything I need to make 15 bow transforming kits.
My Questions are: (I am very out of depth here so these may be very silly - apologies in advance)
Do I need to order additional mating connectors?
There will be soldering be involved, yes? I can probably get my friendly tech elves to do it if required. Although they might prefer if your elves offer that service?
I will be buying the wire in the 2 something metre lengths and cutting to the 50cm lengths.
I also need about 20 cms of regular wire (non light up) to run from where the EL wire finishes (the silver bit in the pic) and down past the hand to the battery pack. (the El wire will be attached to the bow stick most of the way up the bow from there. I am hoping super sticky double sided tape will keep it on.
Cheers
Cathy


#2

If you want to cut the EL wire into segments to use then you will need to do some soldering, same goes for adding additional length to the wire.
There is an instructabe here on how to do that: http://www.instructables.com/id/How-to-Solder-EL-Electroluminescent-Wire/
LittleBird doesn’t currently have any of the connectors available so given your time crunch i would just solder them straight on and skip the connectors. But if you can find them elsewhere they are JST SM connectors.

One last note, you need to make sure to heatshrink or tape the wires well once they are soldered as EL uses reasonably high voltages and it could short itself if too close together. It also gives a hell of a sting.


#3

Thank you James :slight_smile:
I will show my elves and get to ordering asap


#4

oh and what do i need to order for the non light up bit of the wiring?


#5

Looks like fun.

The non-light up bit of the wiring can be a conventional hookup wire with suitable insulation thickness. Since the voltage of the inverter is between 90V and 120V AC, any wire sold in Australia with a 240V AC rating will be fine. It’s kinda hard to find wire with a lesser rating here, although there’s lots of wire with no rating. Black outer would be best, so it doesn’t show up in performance.

If you have longer segments of EL wire than you need, you might also double them up on part of the bow (e.g. two metres in four runs over 50cm), for extra brightness.

For child safety, have your elves check each bow before it is activated for a concert, to check for damage since it was last assembled.

Another idea is to assemble onto a thin strip of perspex, and attach with clips or wire ties before performance.

The performance you link to looks like they were using LEDs and not EL wire. In particular for the yellow bow; spots can be seen. You should be able to get more light flux from LEDs, at lower safer voltage. The performers had cables between their hand and their sleeve, but not on the floor, so there was some sort of power pack in a pocket.

Hope that helps!


#6

Hi, Thank you that is very helpful indeed. Our biggest concern is weight so we are hoping the wire won’t interfere with the bow balance too much. Will make sure the elves check the bows.
I’ll sure our efforts once we are done!


#7

Shouldn’t interfere with balance much, if you keep the same mass on both ends of the bow.

It’s not just balance, it’s also the inertia due to mass on the back of the bow, the glare, and the flickering caused by movement in visual field.

(If they can play blindfolded, they’ve learned based on hearing, touch and proprioception alone, and should be able to tune out the visuals and concentrate on the conductor.)

For particularly young students, with good hearing near the ultrasonic range, they might hear a whistle from the EL wire inverter.

Your students will adapt to the changed conditions with a bit of practice, especially as they want to do it. :smile:


#8

I hope so! They can play by memory and I get them to play with their eyes closed as well. My plan is to place the wire on the front/a little towards the top rather than having it facing them so hopefully it won’t go straight into their eyes. They are pretty excited!
I wondered about the whistle - I had read about that. There will be 15 or so playing plus the accompaniment so I’m hoping that won’t be too distracting. They might hear it at home in their practise. I’ll let you know :slight_smile:


#9

Hi
sorry another question:
If we use EL tape instead of EL wire in 50cm lengths will this inverter - EL wire 2xAA pocket inverter (part number: DF-FIT0229) - run that length of tape?
Thinking the tape might give a more light sabre effect.


#10

EL tape and EL wire are similar in behaviour. You’re right, the tape might give a greater effect; because it will occupy a larger visual space. It will also depend on the lighting at performance. The information for DF-FIT0229 says it will run 2.5m of wire for about 8 to 10 hours, presumably on alkaline batteries. So it should run 50cm of wire for longer. Running time for tape may be different. Test with a time lapse camera app on a phone.


#11

How did I miss this post! So how did it all work out?


#12

Really well! We used EL wire, the elves did some fancy soldering and we ran it back to a battery pack on their waist. I have a videoclip of the kids playing while Vader and a Jedi battle it out in the foreground but I can’t upload it.

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#13

This one has more of the kids


#14

And the costumes, neat. Looks like they had lots of fun! Well done.