Low Cost 24 Led Bike Light Project

Introduction: Low Cost 24 Led Bike Light Project

This is my first Instructable.
I ride my 10 year old boat anchor,
a big box store heavily modified Bike, year round in all types of weather, daily.
Particularly coming home at night from on a 26 mile trip.
I needed something to make me visibly from the back.
And being able to see ahead of me on the back-roads which I travel,
because there are no street lights on some sections for miles at a time.
This Tail and headlight that i built does the job, just fine for now.
So here it goes....

Parts list:

1-  Rayovac 6v Floating lantern flashlight found at Walmart for $3:50
1- Plastic bowl from Moon Sand/Dough container
2 - 6 Led flashlights $3.99 (used only one reflector and both switches from these)
12 - White Super bright Leds $5.99 for 100pcs 20 each color Led
12 - Red Super bright Leds
6 - 47 ohm 1/4 w resistors $2.29 for a pack of 25
6 - 56ohm 1/4w resistors $2.29 for a pack of 25
2 - Hard DVD covers (used a black case and white case form a Wii game for the plastic)
1 - Metal U-Bracket (Scavenged off of an old halogen spotlight)
4 - Small screws (Out of some previous electronics project)
2 - Washers
2 - Old style Shimano SIS shift lever mounts
6 - Bolts
4 - nuts
2 - Cords fora computer monitor for the wire
1- momentary push button normally close switch
Total cost all around $14

Electric or cordless Drill /with Small Drill bits assorted.
Dremel /with cut-off wheel.
Clear Silicone sealant.
Soldering Iron with Solder
Needle nose pliers
Phillips head screw driver
6mm Alan key for the bolts
Vice Grips
Electrical tape
Friction tape 

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Step 1: Dissemble and Parts Recon

Remove the black bezel from the lantern flashlight by unscrewing it.
Take the blue casing and battery as seen in the picture and set it aside.
You only going to use from the large flashlight is
the Black bezel the lens and the reflector.
Here is  the link for the flashlight that I used:
Take a small led flashlights head off and take out leds and the reflector
Push the switch out of the battery compartment, on the cheap Led flashlights they come out fairly easily.
Now you have your large and small reflectors one lens and one front bezel plus power switch.
The flat panel switch have a quarter inch tab on either side.
I put a very tiny, tiny hole in each tab and threaded a few strand of wire threw the holes then soldered them to the switch.
I wrapped both ends with electrical tape and then taped itto my handlebars
Repeats the same for the momentary push button switch that is attached to my brake lever.

Step 2: Things Laying Around

For this light casing i used a Mood Sand or Dough plastic container.
This bowls rim fits over the back of the black bezel of the flashlight about a quarter of and inch.
Took the reflector, light and lens out of the bezel and set it aside so that it won't get damaged during assembly.
Took the black bezel and the plastic bowl and put the two together
Then drilled four very tiny pilot holes for four screws to hold them together. 
Drilled out for four wires coming out of the back of the light.
One wire coming out is for the on/off of the headlight and taillight,.
One wire goes to a momentary push button switch
that is normally closed and is drilled tapped and threaded into
My rear brake level for the operation of the brake light.
(Here's the Instructable later for the brake level switch that I used)
Another wire runs along my top tube and back to my  to the taillight.
And the last  wire runs to the battery pack along the top tube that is located under the seat.
All of the connections are made inside the headlight. 

Step 3: The Head Light

Took the original light fixture off the back of the reflector,
after leaving it on. I test fitted everything with it on for clearances..
There is a small nipple that sticks out on the back of the large  reflector and needs to be cut off.
I used a Dremel with a cut off wheel to do this
Now this gives you a flat surface and a hole to work with.
Took the small reflector and glued in into the center of the large reflector.
Once in place, drilled six small holes around on the small reflector enough o fit the 5mm Leds.
lining the holes up with the ones inside of it.
Placed, 6 White Super bright leds in the small center reflector
and bent down the negative pins of the leds
and face them out ward in a circle pattern.
Then glued the leds in place.
Placed the six outer leds in the holes drilled in the large reflector
and bent the positive legs up
toward the negative pins of the other leds.
Wiring them in series. Soldered all of the center leds positives together
and adding a 4" wire to it.
Used six 47ohm resistors on the negative pins and soldered them.
Then Soldered small wires to connect all of the negatives together
in a circle around the reflector with a single 4" wire coming off of it.

Step 4: Mounting Hardware

I used a metal bracket i had laying around.
It was off of an old spotlight I had.
I drilled two holes in either end on the bottom for bolts
to place the mounting points on either side of my handlebar stem.
I use two clamps off of a set of old style Shimano SIS shifters.
I put two bolts into the clamp and attached the U-bracket to them.
The headlight assembly is held on with two bolts with two washers.
I used some vise grips to bend each side of the U-bracket
in a bit to get the right diameter of the headlight.
I used two small rubber washer between the bracket and the light
when bolting it in to prevent it from moving unwantingly.
The light does not move or adjust while riding.

Step 5: The Tail/brake Light

Used a red Clearance light, designed for 12v lighting
and to be used on a trailer, here is the link:
Pry off the lens from the case with a flat head screwdriver.
Push dow a small tap to slide out the existing light bulb fixture
Then I cut an oval out of white plastic that fits the inner diameter of the oval
with enough room to fit the red lens over it again.
Then cut a piece of black plastic from a DVD case cut this oval
for the back diameter of the casing.
Before i cut out the white plastic where the leds will be placed.
I used a straight edge and drew out lines evenly where the leds should go.
Then drilled out a line of 6 holes down the center of the white plastic oval
with three holes on either side of the center six.
Then center is going to be the brake light
and the six outer is going to make up the tail light function.
There is a quarter inch under the white plastic oval where it goes into the housing.
There only about a quarter of an inch between the led plate
and the casing so putting all 12 Leds and the four resistors
and soldering all in kinda of flat took the longest.
Used a red bike reflector seat post mount to hold this light on.
Drilled one small hole through the black plastic oval and through the white casing.
There was already a square cut out where the light bulb was which makes the second hole.
Added two nuts and two bolts to secure the casing, the black oval to the mount.
I added a strip of tape over the bolts on the inside to prevent any shorts.
Placed all 12 Red super bright leds into the holes in the
pattern I made in the white plastic oval and glued them in place.
I wired them three in series with four 56ohm resistors on the negative pins.
One the leds were mounted and wired,
I used computer power supply cord for this project. 
It has a black outer sheathing on it.
Inside it has three wires, One black, one green and one white.
Used the black as the ground wire.
The white wire for the center strip and the green wire for the outter leds.
Glued the led panel into the case let it dry
and snapped on the red reflector lens.
Sealed up a few small holes in the casing with silicone
and went around the edges with friction tape to hide the exposed white plastic.
Which later on I replaced the friction tape with electrical tape.

Step 6: Switch's and Power

The power switch is soldered to the end of one of the wires
and is just taped with friction tape to the left of my handlebars.
This turns on the tail light and headlight together.
The other switch is threaded into my rear brake lever mount.
And turns on the center strip of six leds on the taillight when ever my brake level is pulled.
The Instrucatable for this Switch:

The battery pack I am using is from a portable DVD player.
I did not take Pictures of this But,
It is a 7.4v Lithium -ion pack @1750mah.
I have it tucked under my seat using a  clip to connect the power.
I use the DVD player to charge the battery pack, when done using it
All 24 leds only draw 300mah,
I do not have a low battery indicator circuit on this setup, Yet
I charge it almost after every ride beyond 30 Miles or so.

This is far from Perfect but the way is ended up as far as design.
Leaves a ton of room for future improvement.
The head light can use a Cree Led in it and can fit a small heat sink on the back
Also the headlight can contain the constant current driver inside it.
The tail light can also host two Cree leds with a heat sink plate on the back.
The battery can be upgraded to a 2S2P Lipo or Lithium-ion battery pack
With a low battery indicator and overdraw circuit.
The wiring could be a bit thinner or at least the same diameter as my brake cables.
The headlight body is much bigger than most light But personally I like the flood light.

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