Ultra-powerful headlamp using LEDs?

[John Doe]

I am looking to make or buy an ultra-powerful head/helmet lamp for
nighttime in-line skating. It requires lots of light for safety
reasons and because skate wheels are small and tend to trip on
unseen things while zipping along.

Please feel free to correct, but (if you can find them) I suppose
three Cree XLamp XR-E 175 lumens LEDs would cost at least $50 by
themselves (what I paid for the Coleman 530 lumens LED spotlight
at Academy Sports and Outdoors). The spotlight includes all of the
necessary components, and I might end up dissecting the thing.
Hopefully the Sealed Lead Acid battery will work in a fanny pack,
otherwise maybe I will use a spare 14.4 V cordless drill battery
through a 12 V regulator. I suppose a NiCad battery is more
expensive but generally better than SLA. Lots of possibilities for
making a very high-powered helmet lamp. My first effort was using
a Brinkmann dual xenon. I probably should have used both lights
instead of cutting the dual reflector in half, but then there is
the runtime issue. Lots of heat too, and then replacement bulbs.

The Coleman LED spotlight is supposed to be 530 lumens with a long
run time. I am guessing that it does put out some bright light but
that it will be bluish. Anybody care to guess how long those LEDs
will last? From reading, I get the impression that good heat
sinking is important to high-power LED lifetime.

FWIW. I was also considering maybe trying to find a dimmable
compact fluorescent floodlight/spotlight and hook it up to my 36 V
lithium ion battery. But besides being somewhat difficult to find,
I do not know whether it would start up or how much light would be
emitted at 36 V. I use compact florescent lights at home and they
all look great to me.

Thanks.

 

[John Doe]

If you don't mind using compact fluorescent lights...would you
consider using a 12V battery + a 75 watt inverter to generate
110V?

That inverter is certainly light enough, maybe efficient enough. I
guess the question would be whether that adaptation would produce
a high power spotlight for normal use.

I've seen inverters like this for about $9 at Ross.
http://www.amazon.com/Kensington-33060-Portable-Power-Inverter/dp/B0000A55F6

Not dimmable though. Is that an absolute requirement?

No, I thought maybe the 36 V battery would be more likely to
work with a dimmable CFL (and produce lots of light).

 

[John Doe]

How about a flare suspended from a parachute?

Realistically, how easy will it be to see small blemishes in the
ground surface with a fast-moving light attached to a skater?

I use 140 mm front wheels.

http://www.flickr.com/photos/27532210@N04/3056505603/

Being able to see larger obstacles from a distance is important.
Getting a general idea of the terrain from a distance is also very
important. When in-line skating, familiarity with the terrain is
everything.

 

[Rich Webb]

I am looking to make or buy an ultra-powerful head/helmet lamp for
nighttime in-line skating. It requires lots of light for safety
reasons and because skate wheels are small and tend to trip on
unseen things while zipping along.

Try over at
http://www.4sevens.com/product_info.php?cPath=22&products_id=1774. The
Fenix lights have embedded DC-DC converters. I keep one now as my
toolbag light, one for general purpose around the house, and a smaller
AAA on the keychain. Not cheap but I've been happy with them.

 

[John Doe]

three Cree XLamp XR-E 175 lumens LEDs [in the] Coleman LED
spotlight

Very bright, almost normal white to my eyes. Extremely
concentrated/narrow beams with a very dim surrounding light.

The LED modules are surface mounted (looks like six contacts) on a
T-shaped circuit board. That circuit board is screwed onto a large
heatsink with white thermal paste/foam in between. The LED circuit
board has only two inputs, plus and minus. The heatsink is 3 1/2"
diameter x 3/8" thick.

To take the thing apart, just pop off the front and back parts of
the handle and unscrew.

 

[Michael Black]

They sell lots of headlamps in camping stores. I bought one from
Eastern Mountain Sports a few years ago. They made some that where
even brighter than the one I bought.... actually for walking the dogs
through the woods at night I find that even the lowest setting of the
head lamp is too bright. Once your eyes become dark adapted you don't
need much light to see.
Anyway, you could buy one of these.. and if not bright enough you
could buy several more. (Well that would look pretty funny.)

And once you start using a bright light, you're stuck with it. It ruins
your night vision, so anything out of the beam of light is invisible.
So another someone coming from a sidestreet without a light may not be
seen until they ram into you.

Traditionally, lights on bicycles have been to indicate presence. A red
on the back and a white on the front, so you are visible. It is about
relying on night vision to see properly.

Michael

 

[John Doe]

George Herold wrote:
And once you start using a bright light, you're stuck with it.
It ruins your night vision,

You are supposed to shine the light AWAY from you.

so anything out of the beam of light is invisible.
BWAAAAAHAHAHAHAAAAAA!!!

So another someone coming from a sidestreet without a light may
not be seen until they ram into you.

Hey there ET... Here on Earth, vehicles have reflectors. A light
does a very good job of lighting up reflectors. A light like the
one I am putting on my helmet will light up everything from here
to your planet.

Traditionally, lights on bicycles have been to indicate
presence. A red on the back and a white on the front, so you
are visible.
BWAAAAAHAHAHAHAAAAAA!!!

It is about relying on night vision to see properly.

Tell that one to millions of police officers here on earth, ET.

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