This article is from the Misc Bicycles FAQs, by various authors.
From: Arnie Berger <firstname.lastname@example.org>
This article is a bit wordy. One picture is worth 1000 words, but
pictures don't lend themselves to ASCII E-MAIL, so please bear with me.
The objective was to build a bright lighting system for bicycle
commuting. I already had a bike light that I built using an old 6V,
12 Watt sealed beam emergency light and a 6 volt rechargable battery.
This has served me well for 4 years of regular commuting. Then, our
work group was moved to a different facility and my lighting requirements
changed. The only safe and direct route was through a city park on a
dark trail with rocks and ruts. I solved one half of the problem by
buying a mountain bike. The other part of the problem was solved by this
I suggest that you read this very long article completely before
starting. If you don't understand something, write to me and I'll try to
elaborate. These plans carry no warranty, whatsoever. It only describes how
I built my bike light.
Also, several people have pointed out that that the cost of materials
is in the neighborhood of $100. This may or may not be true for you,
depending upon your "do-it-yourselfer index". I built this light because
I wasn't satisfied with what was commercially available and I was curious
about how good a homebrew light I could build. My personal investment was