But you know what REALLY annoys me? My Incandescent dynamo taillights and the amount of tiny little bulbs I've been through over the years! If there's one thing that everyone here on Instructables knows "If it can be made better with an LED, then what the HELL are you waiting for?"
This instructable was created for the 2013 bike competition, It basically substitutes the dynamo system with a closed unit LED system that is triggered using a magnetic switch so to completely maintain the original look, integrity and beauty of the taillight while providing the convenience of a long-life lithium-LED set-up.
I had been thinking about doing the conversion for a few months but the competition gave me the kick in the butt I needed, so here it is!
Strap in Retrophiles, your 1960 stylings are about to meet 21st century reliability!
Step 1: To Begin
Parts & Tools You'll Need
- Your original bike taillight
- 1 cheap LED bike light - One of the small ones, preferably red with a flashing function.
- 1 small Reed Switch - A type of magnetic switch, I salvaged one from an old cycle computer sensor, but any electronics store will have one.
- A small Neodymium Magnet.
- Some thin insulated wire - Again I salvaged some from the cycle computer, you don't need much, 30cm or so.
- Some decent Electrical or Gaffer Tape.
- A Soldering Iron, Solder and a Solder Sucker (If that's the way you roll).
- Willingness to part with tradition.
Find a comfortable place to work with your bike close at hand, Let's get started.
Step 2: Out With the Bulb...
Once the plastic cover is off, unscrew and remove the light bulb from within, if you want you can keep it to show your kids, one day.
As you can see there's STACKS of room inside these things. Keep in mind the general shape of your unit as we are going to have to eventually fit all our components inside, snuggly.
You can leave your bike alone now. Grab your LED stuff and crank up that soldering iron (Provided you know how to use one, careful now)
Step 3: ... and in With the New.
Start by removing the covering, on this particular light it's silicone and is easily removed with some wrangling, some similar lights that have a plastic outer shel and an elastic mount can be disassembled with a small screwdriver.
Step 4: Salvage.
Step 5: Desoldering the PCB
Start by noting where everything is situated, the orientation of the LEDs and the battery orientation.
Start to remove the LED assembly, this is the most difficult part as you may need to use a solder sucker to clear the PCB of all solder before the LEDs will budge, take it slowly and don't leave the soldering iron on the PCB for too long as you may dammage the board.
The existing momentary switch may have some tape covering it, you want to remove both the tape and the small piece of springy metal that forms the momentary switch so the terminals can be soldered to.
Step 6: Wiring
Solder the reed switch and the LED assembly to their dedicated wires.
Step 7: Add the Battery
Before sealing the battery assembly hold the wires on the correct battery terminals then touch your Neodymium magnet to the reed switch briefly and check the circuit works. If not; Double check you got the polarity of the batteries right, if it still doesn't work check your LEDs are wired correctly and failing that troubleshoot - check over your soldering work.
If she lights up, seal the batteris and the PCB snugly and neatly in gaffer or electrical tape
Step 8: Rough Fit
What you want to do is fold the wires so they poke into the bulb mount cavity, holding the LED assembly in place.
When you've shaped the wire satisfactorily use the old globe as a guide and wrap the wires to make a plug for the globe mount.
And that's it, grab your magnet and test it out but swiping it over the area where you placed the reed switch.
Step 10: Plans...
I'd love to develop a solar rechargeable version of this type of sealed light for my more modern bikes as a theft proof device, if anyone has any ideas on improvement I would love to hear them!
Thanks for checking out my instructable, Enjoy and happy converting!