Heatsink for D-cell Maglights???

Would like to mount a ls in the body of a D-cell Maglight. What is the best/easiest way to make a heatsink that fits in the top of the Mag body?

Since entire flashlight is metal and it is always connected to the negative battery terminal, why not tie Luxeon heat-sink with the LED's negative terminal?

My assumption is that if there is a path for the electrons to pass, then the same path can be travelled by the heated molecules

Seriously, would few of our esteemed resident thermodynamic gurus (Doug and/or Wayne etc) point out the flaws in my reasoning?

Thanks,
- Vikas

- Vikas

Originally posted by Ben H:
Would like to mount a ls in the body of a D-cell Maglight. What is the best/easiest way to make a heatsink that fits in the top of the Mag body?

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<font size="2" face="Verdana, Arial">Vise. Hacksaw. File. Agony.

Wayne J.

Say it ain't so!!!

Vise. Hacksaw (blood). File (sweat). Agony (tears).???? A labor of love or insanity.....I can't decide.

Anybody have any luck cutting aluminum plate with a hole saw?

Thanks,
Ben

Heck yeah. You have to use caution when cutting as the mandrel is not used. The piece needs to be well clamped to the drill press table.

Originally posted by Ben H:
Say it ain't so!!!

Vise. Hacksaw (blood). File (sweat). Agony (tears).???? A labor of love or insanity.....I can't decide.

Anybody have any luck cutting aluminum plate with a hole saw?

Thanks,
Ben

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<font size="2" face="Verdana, Arial">I have tried that. The problem is that you need to have the disc within .001 to .002 of the size of the flashlight body.

I have a machinest cut me the discs, for my other flashlights, but Mag is a size of it's own. I did have discs made for the Mag, when I was modifying them.

When I do it by hand, I draw a cirle on the aluminum plate. Then I secure it in the vise, and cut out the disc, very crudely, with the hack saw. Then I file it, compare, file, compare, until I get it just right, so it fits snug into the opening.

I also grind off all the anodizing on the inside of the flashlight body near the opening, so the aluminum disc contacts bare aluminum, for better heat sinking.

Another method, if that seem insane (it is), is to make the disc about the size of the body opening, and mix up some epoxy with heat sink grease, and epoxy it onto the end of the flashlight. This works too. I don't know if it transfers the heat as well, though.

Another option is to buy a lathe.

Enjoy!

Wayne J.
www.elektrolumens.com

Originally posted by lambda:
Ben,

I have some nice round heatsinks for Mag mods. Check out http://lambda10.tripod.com/3dmag.htm for a write up of the mod and pictures of the heatsink.

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<font size="2" face="Verdana, Arial">Oh yeah, I remember those. I have a few of them too. I never really used them though, but I'm sure they work great. Hey, that's where I got the idea from in the first place!

Wayne J.
www.elektrolumens.com

Ben,

I have some nice round heatsinks for Mag mods. Check out http://lambda10.tripod.com/3dmag.htm for a write up of the mod and pictures of the heatsink.

Originally posted by lambda:
Ben,

I have some nice round heatsinks for Mag mods. Check out http://lambda10.tripod.com/3dmag.htm

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<font size="2" face="Verdana, Arial">I must say that these sinks that lambda has are wonderful...

Thanks for all the input! I'm having a local job shop quote some Al discs for me. If the price isn't outrageous I'll get some from them. I tried the hole saw last night....the disc was undersized about 1/16". So close yet so far away.

Lambda: Your heatsinks look great! Do you still want $3 for your heatsinks?

Originally posted by Ben H:
Thanks for all the input! I'm having a local job shop quote some Al discs for me. If the price isn't outrageous I'll get some from them. I tried the hole saw last night....the disc was undersized about 1/16". So close yet so far away.

Lambda: Your heatsinks look great! Do you still want $3 for your heatsinks?

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<font size="2" face="Verdana, Arial">Until you get a machinest to do the work for you, you could try cutting it with a hack saw. It's not as hard as it sounds. Draw the circle on the aluminun, and then begin cutting off pieces. When you get it close to the size, then you begin to use a metal file to shape the disc. Aluminum is soft and cuts and files quite easily. At first it would take me about 30 minutes, but now I can do it in about 10 to 15 minutes. Chamfer the edge that presses into the flashlight, to help it go in easier.

I break out the glass of a light bulb, and solder wires onto the bulb base, and then put it into the bulb holder. In the heat sink is a hole to pass the wires. If you use a Luxeon Star w/o, drill the holes, and bolt it on. Solder the wires. You can either enlarge the hole of the Mag reflector, or just leave it out.

With that setup, you should be able to go direct drive, from even 3 'D' cells, without any overheating problems. However, if you put in 1 ohm resistance, the battery life almost doubles. A slightly less bright light.

Wayne J.
www.elektrolumens.com

Ben you would do better to email lambda instead of catching him here... some times he is sooo busy modding that he dosent' always catch every post. Mike

Originally posted by Bushman:
Ben you would do better to email lambda instead of catching him here... some times he is sooo busy modding that he dosent' always catch every post. Mike

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<font size="2" face="Verdana, Arial">Sometimes I make it hear to read also!

Yes, I still have some of the heatsinks left; 2 for $3 including rubber tire and shipping.

I have a lathe. (rather, my dad does) Perhaps I should say "I have access to a lathe."

On Monday I'll hopefully be able to stick it in the garage and put the 120v motor on it. Nice quick-change gearbox for the feeder, too. Huge 72" bed on it. Little bit overkill for making heatsinks. For my 5w-LS mod I'll likely make a heatsink-plate out of a 0.75" chunk of Al I have, and thread a hole thru the center, for a threaded aluminum rod that the Emmitter will be mounted to. Prototyping is fun.

I want to thank you all for your great input. Last night I made my first heatsink out of 1/4" Al!!! It took a LONG time, but the results were better than expected. I used ElektroLumen's recommended tooling: hacksaw, file, and a little Dremel mixed in. I'm thinking this 1/4" heatsink should keep my ls at a very comfortable temp.

Lambda, I'm sending you an email.

Originally posted by Ben H:
I want to thank you all for your great input. Last night I made my first heatsink out of 1/4" Al!!! It took a LONG time, but the results were better than expected. I used ElektroLumen's recommended tooling: hacksaw, file, and a little Dremel mixed in. I'm thinking this 1/4" heatsink should keep my ls at a very comfortable temp.

Lambda, I'm sending you an email.

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<font size="2" face="Verdana, Arial">Hey Ben,

Nice job! Lot's of work, huh?

I use the same method of madness to make heat sinks to use in my Brinkmann 3AA mods. (Not really doing anymore.)

In a few weeks I'll have in the first load of StarLux's from the manufacturer. I'll be so busy assembling these, I doubt I'll have much time to cut out heat sinks.

Wayne J.
www.elektrolumens.com

Hi Wayne,

I took a different approach with my Brinkmann 3 AA mods. I only had a ls on the hex pad, so I rounded off the corners until it fit in the head. I sanded one side of a copper penny smooth and put all that in the head with some thermal compound. I glued the head to the body with some thermal epoxy, and the thing works great.

Did you use a ls emitter with the heatsink attached to the body of the flashlight?

It's a bummer we all aren't neighbors......if we combined all the knowledge, skill, and resources we could have one sweet flashlight company!!!!

I pray your StarLux's go together much faster than my 3D Mag is going to!

Have a great weekend!
Ben

Hey- how 'bout we all move to The middle of nowhere, and start a town w/o streetlights....

If I can get the lathe running, I might be able to crank out 3 kinds of D-cell Mag sinks- oversized (you file down to exact for YOUR mag), undersized (get my epoxy, ma!), and 'pound-in' (tight enough to require removal of finish inside mag-barrel, and a medium-large hammer).

PsycoBob[Q2],

I've played with that idea in the past, but found that Maglites varied too much from unit to unit to get the proper fit from a universal size. You can get close, but it just wasn't close enough to be reliable for all the production runs they've made over the years.

Originally posted by Ben H:
Hi Wayne,

I took a different approach with my Brinkmann 3 AA mods. I only had a ls on the hex pad, so I rounded off the corners until it fit in the head. I sanded one side of a copper penny smooth and put all that in the head with some thermal compound. I glued the head to the body with some thermal epoxy, and the thing works great.

Did you use a ls emitter with the heatsink attached to the body of the flashlight?

It's a bummer we all aren't neighbors......if we combined all the knowledge, skill, and resources we could have one sweet flashlight company!!!!

I pray your StarLux's go together much faster than my 3D Mag is going to!

Have a great weekend!
Ben

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<font size="2" face="Verdana, Arial">I make a heat sink which fits on the end, and epoxy it to the body with heat sink epoxy. I use 1/8" thick aluminum. I drill holes through it for the wires, which I push into the electrical contact holes. I epoxy the emitter on, and then solder the wires. A lot of work! With the Lambertian high domes, the stock reflector focuses the light quite well, but the reflector must be modified to work.

Wayne J.
www.elektrolumens.com