A homemade LED headlight for a bicycle dynamo (hub generator).

Assembly methods:

There are four pieces for the lens/LED assembly:
* lens (L2 OPTX 6 degree spot beam)
* adapter (small piece of aluminum that makes the lens fit into the body of the headlight)
* LED (you can see the edge of the star there)
* heat sink.

The lens is held in place super glue to both the LED and adapter ring. The heat sink is epoxied to the LED using heat conductive epoxy.

The tail cap threads on with 24 TPI threads (cut on the lathe).

The lens assembly is a tight fit and stuck in place with thermal grease. I had to use a sharp knife to pry them apart. It would probably be easier to make the tail cap stuck in place the same way.