Introduction: Colour Changing USB Light
Here is a light made from a plastic bottle, fishing line, an old USB cable and a slow colour change RGB LED.
The nylon thread (fishing line) does not have quite the same effect as real optical fibres. There is more light signal degradation along its length so it doesn't have the same bright point at the end of the fibre. Although the diffusion of light along its length still looks kind of neat.
I included an optical fibre that I plucked from my Christmas tree as a comparison.
Step 1: Materials:
- small plastic bottle
- nylon fishing line or jewelry thread
- usb cable
- 5mm RGB slow colour change LED (I got mine on eBay) and a resistor
- spout from a cooking oil bottle
- clear drying glue and clear packing tape
- twist ties
- plastic bottle with desired circumference (see step 4)
- paint brushes
- soldering iron
- glue gun and glue
- ruler and measuring tape
- something sharp to use to poke a hole in the plastic bottle.
Step 2: Preparing the Base
- Remove label and adhesive from your plastic bottle, if you have trouble getting it off you can try a product like Goo Gone.
- Near the bottom of the bottle poke a hole through the plastic for the USB cable to fit through (from my pictures you can see that I made the hole after I painted -that was not a good idea because I had to go back and touch up the paint).
- Paint the bottle, I chose black because I didn't want any light from the LED to seep out the bottle. Apply several coats if necessary.
Step 3: Preparing the Light
- Cut off the extraneous end of the USB cable with pliers.
- Peal back insulation, exposing the wires underneath. Cut off the green and white wires.
- Removing the plastic casing at the ends of the red and black wires.
- If you are just using one LED, solder the red wire to one end of the resistor.
- Solder the other end of the resistor to the positive leg of the LED (this is the longer leg).
- Solder the ground leg of the LED (this is the shorter leg) to the black wire.
- Test it out -plug your cable into computer to make sure it works
- Trim off excess wire and wrap it up with electrical tape.
Step 4: Preparing the Fibre
- Tape one end of the nylon thread/fishing line to the container.
- Wrap thread around bottle, many times, don't worry if some of the treads overlap the length doesn't need to be exact.
- Cut across the length of the threads (see image below), hold the bundle together with twist ties.
- Repeat until you have a large enough bundle of nylon thread, I did it 3 times.
Nylon tends to hold it shape when cool, this is referred to as line memory. So when it is wrapped tightly around a spool and waiting for you to wander into a store and buy it, it will take on the shape of the spool. So rather then having a nice straight thread/fishing line it comes out in curls. I had this problem with my jewelry thread, to remedy this; place the bundle in a shallow bowl and pour boiling water over it. Allow the water to cool. The nylon will become straight.
Trimming and gluing the bundle
Use several twist ties along the length of the bundle to keep all of the threads together
- take the bundle of nylon threads and cut in half, so that they are approximately 10cm in length now.
- take one end of the bundle and try to line up all of the threads as best as you can. With scissors trim off about 1/4-1/2cm so that the end is even.
- pour glue into a small cap (I used the cap from the water bottle) and dip in the end of the bundle that you just cut. Allow excess glue to drip off.
- Take a strip (~2cm in length) of packaging tape and wrap it tightly around the glued end of the bundle.
- Allow the glue to dry, then trim off any excess tape so that one edge of the tape is flush with the end of the bundle.
Step 5: Putting It All Together
- Use a twist tie to hold the nylon bundle of thread in place with the taped end in the spout (or lid, if that is what you are using), apply glue with a glue gun around the bundle, fill in the gaps and make sure it is secure.
- Paint the over the area you glued.
- Drop some pebbles into the base of your light. When it starts to get full, manoeuvre your light into place. Make sure it centred and just under where the nylon bundle will be.
- Fill the bottle the rest of the way up (~3/4full) with the pebbles to keep the light in place.
- Place spout/lid on the base and plug into computer, dim the lights in the room and enjoy the pretty colours.