5w LS size limits ?

I love small bright flashlights (yes like most of you guys ) and was wondering what would be the size limit for a 5w LS (running at full voltage/current specs.)

I have seen some great mods by CPF members, but most seem to be housed in fairly large bodied flashlights (4D-5D cell), a bit large for EDC.

Begging Section Starts Here

Would anyone be interested in building me a fairly small (lets say around Legend LX size) 5w (Cyan or Blue) flashlight ?
Brightness is more important than battery life, but if possible I would like at least 30-45 minutes of very bright light.

If you are interested, please give me a rough idea of the total price (would need to be shipped to the UK)

Payment by Paypal would be preferable, but would be happy to discuss other options.

Thanks

The smallest 5W LS flashlight that could be built with easy to get components will not be battery limited, but will be heat sink limited. 5W of heat in a small light simply has no where to go, and the light will get hot, and the LS junction even hotter.

Using 1/3AA NiCd cells, you could power a 5WLS in a 2AA maglight without any control circuitry at all. (Well, you might need a bit of resistance to protect the LS from the low internal resistance of the NiCd cells.) However you would need to be very careful with heat sinking to carry heat from the LS emitter, the light would quickly get _hot_.

I figure that a good machined copper heat sink attached to a set of 5 or 6AA cells is probably about the smallest you could go and have continuous operation capability.

-Jon

I have a Garrity 2AA stainless steel flashlight, which will hold 3 Lithium 123 batteries quite well. I have already made a cyan 5W pill for it. I plan to put the pill in this flashlight, using the 3 Lithiums. Probably use a little resistance. The problem will be to sink the heat. So I am designing a funny heat sink head for it. It's just for fun. It will work, and look very strange. Lithium batteries are a bit expensive, but if a person wants a small flashlight, putting out 120 lumens, this would be it.

I also have discovered that a 9V battery powers the 5 watt just fine. Short battery life? Yes. This could be the worlds brightest pocket light, at 120 lumens! Of course, I could only use it for short intermittent use. The only possible use would be just to WOW my friends. I was playing around with some different ideas of heat sink last night. Not a practical light, but fun.

Did you see my post on the cyan 5W LS modified Brinkmann LX? Direct drive from 6 volts, 960 lux, and uses a 1" acrylic ball for a lens.

Wayne J.
www.elektrolumens.com

Originally posted by ElektroLumens:
The only possible use would be just to WOW my friends.

Click to expand...

<font size="2" face="Verdana, Arial">Same here

Wayne J,

I would be very curious as to your findings using the stainless as a heat sink portion, if that is your plans. I have unwantingly stayed away from stainless as well as titanium as both metals are very poor thermal conductors. I use stainless in some clustered LED fixtures where heat is not as big of a problem; .6 watts in my 9 LED fixture. The Stainless housing gets to about 107 F but it seems to take a while getting there.....

- Don

Originally posted by McGizmo:
Wayne J,

I would be very curious as to your findings using the stainless as a heat sink portion, if that is your plans. I have unwantingly stayed away from stainless as well as titanium as both metals are very poor thermal conductors. I use stainless in some clustered LED fixtures where heat is not as big of a problem; .6 watts in my 9 LED fixture. The Stainless housing gets to about 107 F but it seems to take a while getting there.....

- Don

Click to expand...

<font size="2" face="Verdana, Arial">Like I had mentioned, I will be making a aluminum heat sink head. I realize stainless steel is a poor heat conductor. This flashlight probably would not be for prolonged use either, unless I make a giant aluminum head for it. As others have mentioned, heat sinking is the need, and size matters!

Wayne J.
www.elektrolumens.com

OK...I don't know much about modding, BUT...how about this for a sink....Copper flashing that is used for roof repairs. Cut a disc of it, space it with a small copper washer , then have another disc....repeat as necessary...instant copper fins.

Wayne J., your thoughts about the 9v option made me curious. Have you tried this yet? If so, did you use any resistance, since 9v is more than the 5W maximum? About how long would you suppose this would last?

Thanks!

Originally posted by Orion:
Wayne J., your thoughts about the 9v option made me curious. Have you tried this yet? If so, did you use any resistance, since 9v is more than the 5W maximum? About how long would you suppose this would last?

Thanks!

Click to expand...

<font size="2" face="Verdana, Arial">Yes, I have tried it, that's how I know it works. No resistance. Might last 5 minutes? This would only be for the WOW effect. Pull it out of your pocket, and light up the block, then put it back. There wouldn't be enough heat sink, so you couldn't use it more than a few seconds?

Wayne J.
www.elektrolumens.com

For heat problems you need lots of surface area. I don't know much about machining aluminum, but how hard would it be to make a tube with ridges/grooves that run the length of the tube? If these were fairly deep and circled the whole battery pack you would get around twice the surface area without adding a lot of bulk. It would also be a nice surface to grab without a sandpaper-like gnurl (assuming rounded corners) and would even have a small anti-roll effect.

Would something like this make a 2-3 CR123a sized 5W light feasible?

- Russ

My DD 5W cyan in Legend LX only gets to 97F max, and light output is still brighter than any 1-watt mod out there...

But to get the absolute brightest output from a 5W with minimal heat related damage, I would say that you'd need a big body, a Lou Ferrigno body, an Ah-nold body...

Originally posted by MR Bulk:
My DD 5W cyan in Legend LX only gets to 97F max, and light output is still brighter than any 1-watt mod out there...

But to get the absolute brightest output from a 5W with minimal heat related damage, I would say that you'd need a big body, a Lou Ferrigno body, an Ah-nold body...

Click to expand...

<font size="2" face="Verdana, Arial">So if I ever sell a 5D flashlight with a 5 watt LS, should it ba called "Ah-nold"? The 'Ah-nold' flashlight! How about "FerrignoLux ?" Maybe "ZillaLux?" Size matters!

Wayne J.
www.elektrolumens.com

Who is "Zilla"?

As in Godzilla, I think.

Hey, there's a good name for someone's light - Luxzilla..

Graham

Wayne --

Modzilla!

and for the cyan version, Modcylla!

Do what the computer weenies do when they want the ultimate thermal conductivity- Use a lump of silver.

Fill the head of your light with molten silver (let cool), machine the end, and mount the LS. Or just get a piece of silver and machine it, if you can't afford enough silver to fill a mag-lite's head....

So when is someone going to make a Tim Allen's 5w light? 20 5-watters, mounted on a copper block, with ball-lenses for all... and a backpack with a car-battery to run it, and a water-cooling system to keep the LS's cool. (is this an entry for the 'Stupid flashlight contest' yet?)

Can I just pop in and nag one more time to say that (Actual siver is different of course) using thigns like thermal epoxy is not a substitute for real and proper heat sinking, and that means a hunk of metal. LEDs are ever so slightly different, but with CPUs--the thinner the layer of thermal greese (Artic Silver ) the better.

yes- the best thermal goo/epoxy in the world sucks compared to a monolithic piece of aluminum/copper/silver. I just want a Star-trek replicator, so I can have a solid-diamond light to mount my 5w LS's to... Diamond is apparently nearly a superconductor of heat.

Has anyone done any real research on ablative materials? Do some searching about the composition of the space shuttle tiles and what they are made of, basically they are about 98% pure silica, i know most members here are into various degrees of technology and some are just starting but I do have an extensive background in certain areas such as welding and fabrication, mold and die making, machine shop and thermodynamics plus some engineering skills of electrodynamics and transfer rates of conductive materials, part of the list anyway.
I have some intentions of manufacturing some.180- .250" thick composition discs that are heat fused of sintered copper, alum, and silica that are workable and and still retain composition whithout being overly brittle. Rockwell hardness will be very low so its machineable. Process is simple, mixture is pured onto thick walled cylinder, machined plug is installed and whole thing is compressed under 20+ tons of pressure and heated to about 2200 deg. after it is removed its then sliced into discs, could do single die pieces if assembly line technique was desired. an old job of mine had such a heated die and platen. and old hydraulic cylinder is what i have in mind. perfectly round and heavy enough to compress, heating may be tricky with a torch and maybe all i need is about 500 deg. we will see.

xray
I could build you a small torch using a 5watt luxeon,Do you want any other realistic features?
I have a extended 5 watt fliklite ls that runs on 3 123 lithuims its ok but working on a brand new design for the 5 watt ls.
Be good to know your price limit.
Cheers fliker