An Idea for a heat sink to replace H3 bulb with LED

Norm

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Making a heat sink to replace a H3 bulb would give us access to cheap hosts, for instance million candle power lantern type host, making it possible to have an LED run at maximum current and still have long runtimes because of the extra room for batteries and the advantage of a larger reflector.
I've just started to think about this, so all suggestions are welcome.
I don't even know if the reflector in one of the lights is suitable for LED.
Here is what I have in mind.
The heat sink would be retained in the reflector by the earth screw. The reflector I have is metal so there should be no problem with heat sinking.
Any suggestions welcome, If someone decides to make one, please make two :)

My idea would require a heat sink something like the picture, no dimensions at the moment but I could add them if someone is interested in having a go at making it. I don't have a lathe

pic1fe3.jpg


Same picture with the bulb overlaid to give an idea of relationship of the bulb placement to the heat sink.

pic2zd2.jpg


This is the sort of thing I had in mind. But with a broader base for extra heat sinking.

PICT0199.jpg

From this thread http://www.cpfmarketplace.com/mp/showthread.php?t=141994
Thanks AW I hope you don't mind me using your picture as an example.
 
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Keep in mind that you would want your LED to be at the same level as the filament in the glass capsule for proper focus... Otherwise, it looks/sounds like a decent idea!
 
and don't forget about heat dissipation. moving heat away from the led is just the first step. :)
 
Sorry to say, but in all the reflectors I tried Leds in, they have to be placed WAY other than where the filament was - much less inserted.
 
Perhaps a prototype with a threaded post for the LED would be the best way of determining the best focus point. I'm going to have a go using a piece of 6mm aluminium cut out with a hole saw and a brass bolt for the LED post, using two nuts I'll be able to move the LED position, it might be best for any heat sink to be made this way, so as to allow for adjustment for any reflector. If someone could machine something in aluminium that would be perfect.
Norm
 
Making a heat sink to replace a H3 bulb would give us access to cheap hosts, for instance million candle power lantern type host, making it possible to have an LED run at maximum current and still have long runtimes because of the extra room for batteries and the advantage of a larger reflector.
I've just started to think about this, so all suggestions are welcome.
I don't even know if the reflector in one of the lights is suitable for LED.
Here is what I have in mind.
The heat sink would be retained in the reflector by the earth screw. The reflector I have is metal so there should be no problem with heat sinking.
Any suggestions welcome, If someone decides to make one, please make two :)

My idea would require a heat sink something like the picture, no dimensions at the moment but I could add them if someone is interested in having a go at making it. I don't have a lathe

Same picture with the bulb overlaid to give an idea of relationship of the bulb placement to the heat sink.

This is the sort of thing I had in mind. But with a broader base for extra heat sinking.

PICT0199.jpg

From this thread http://www.cpfmarketplace.com/mp/showthread.php?t=141994
Thanks AW I hope you don't mind me using your picture as an example.

Good idea. In fact it was such a good idea that I tried that over a year ago. You can see the hand made prototype heatsink I created in my old post:

http://candlepowerforums.com/vb/showthread.php?t=123003

Final design:
IMG_5861.JPG



It does work, but the reflector totally sucked with an LED source :( . If you were to try it with a different reflector you would probably get different (hopefully better) results ;)

Will
 
Thanks Will, just goes to prove that there is no such thing as an original idea, very interested in what you've done in your thread, it is exactly what I had in mind except I wanted to leave a larger disk at the back of the reflector for heat sinking. How well did the one you made handle the heat from the LED?
Interestingly the bulbs must have some variance in the the position of the filament the bulb I have only measures .63" where yours looks like it was .80"
Thanks Norm
 
Thanks Will, just goes to prove that there is no such thing as an original idea, very interested in what you've done in your thread, it is exactly what I had in mind except I wanted to leave a larger disk at the back of the reflector for heat sinking. How well did the one you made handle the heat from the LED?
Interestingly the bulbs must have some variance in the the position of the filament the bulb I have only measures .63" where yours looks like it was .80"
Thanks Norm

Norm - I don't mean to discourage you - You still have a new/novel idea with the larger heatsink; mine was something slightly different trying to replace the actual bulb ;)

As to the height, I actually found out by experimentation that I had to move the module back in order to get best focus, so yes, .63" or even less would be nice. The problem is trying to use a reflector designed for the bulb to work well with an LED that has a different light radiation pattern :D

Will
 
Not discouraged at all Will, just interested to see the work you had done.
Norm
 

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