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Battery "free" bike light.

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  Step up and get your own "dynamo hum"...(FZ).  All jokes aside, its a simple dynamo light mounted to a Planet Bike light bracket.  On about 6 cranks I get 20 to 25 minutes of light.
  There is a 3.6 volt NiMH rechargeable battery that comes in the light.  SO, by free I refer to your out of pocket cost on batteries.

 
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Step 1: Material

1. dynamo light....Harbor Freight, 2 for $8.
2. quick release light strap...most have a screw to change the mounting base, this is a Planet Bike
3. super glue
4. fingernail polish remover........or acetone

Step 2: Light base

Remove the screw and discard the top thin portion.

Step 3: Level base

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Use a knife to take any high points off of the base.

Step 4: Break light down

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Take the 4 screws out of light.
Be cautious not to let any gears or gear shafts to fall out.

Step 5: "drill" hole for screw

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Using a hole punch I twist and push a hole through the plastic, working from both sides.

Step 6: Prep for glue

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Using the fingernail polish remover, I clean both surfaces.

Step 7: Glue

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1. I put glue on the base only.
2. Screw light cover to base.

Step 8: Put it back together

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Once glue is dry, put your 4 screws back in and your done.

Step 9: Get rolling and give it a crank!

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The law (here in Arizona) says you need a forward facing light visible from 200 yards.  This covers that and I only need a rear red reflector.  So, I'm now battery free!
crapsoup1 year ago
i like it. This is going on my bike very soon
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onrust (author)  crapsoup1 year ago
back @ you man!
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Celt4 years ago
No no no, you see, its a dynamo-charged rechargeable battery, so you do not need to replace them.  Just crank the dynamo to recharge the internal batteries.  This is pretty cool, now imagine if you attached a cable from the dynamo to your wheel!  (hands free charging)!!
Ganoderma Celt4 years ago
Yeah, then you just have a normal light like found on about every bike. 
Celt Ganoderma4 years ago
but the battery lasts soooo much longer.
randomray4 years ago
Good instructable . Good not to have to worry about your batteries dieing on your ride . I do recommend having a cheap red blinky light for the rear it be seen much better then a reflector . In the same vein lights or reflectors on pedals make you much easier to see also .
602poop4 years ago
NICE, anything not to purchase batteries!
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XOIIO4 years ago
Yeah, um these do have batteries, they just recharge.
onrust (author)  XOIIO4 years ago
Are you positive?  I was told it was a capacitor.
Of course I may be wrong, and that's cool.
XOIIO onrust4 years ago
Yes, I've taken apart 10 or so of that kind of light. Each of them had lithium ion button cells.
onrust (author)  XOIIO4 years ago
Yes, you are correct. 
Since it was featured,  I'm not going to edit it.

XOIIO onrust4 years ago
It doesn't bother me if you edit it or not, I just like solving little misunderstandings and helping people understand how things work. 
onrust (author)  XOIIO4 years ago
  I thank you because I learned more about it......I went ahead and edited it anyways because it was wrong.  I'm also new here and thought I could not edit once it had been featured.
  Stay on point, please.  I WILL do more stupid stuff in "public"!
TheZuke!4 years ago
Awww!
I was hoping it would charge via the pedals or wheels...
rimar20004 years ago
Anyway, with or without battery, is an excellent instructable. And if there are  batteries, but they are loaded by hand, are welcome.
hold it
so this is a "Battery free bike light"
with a Battery in it ??????
onrust (author)  thelastonekills4 years ago
I'm no tech, but I do believe that the dynamo charges a capacitor.
In the picture you can see it in blue shrink  wrap. 
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XOIIO onrust4 years ago
Why would they shrink wrap a capacitor? I bet that you can see a line sticking up from one end to the other, which is a wire underneath. I can almost guarantee that if you rip/cut that open there will be button cell batteries.
i agree, i know he probably means no batteries needed to be inserted, and i understand that that doesnt fit in the title, but its also kind of deceiving...

but its a nice idea, nice instructable, and it works pretty good i think ;)
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