EEVblog Electronics Community Forum
Electronics => Beginners => Topic started by: pfleenor on December 14, 2018, 07:59:41 pm
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I'm planning to build a wooden & epoxy lamp similar to this https://www.pinterest.com/pin/71705819045683574/ (https://www.pinterest.com/pin/71705819045683574/)
There are tons of youtube videos of builds but no one mentions if heat of the light is a factor and I'm having a hard time figuring it out.
There won't be any holes in the wood for ventilation. Would something like this work to embed beneath the epoxy?
https://www.ebay.com/itm/Original-CREE-10W-XML-L2-Warm-White-LED-Chip-Base-For-Flashlight-Torch-Light/152933793046?hash=item239b907d16:m:meS570C_z-EvE71_T3eo5kQ:rk:36:pf:0&var=452699757422 (https://www.ebay.com/itm/Original-CREE-10W-XML-L2-Warm-White-LED-Chip-Base-For-Flashlight-Torch-Light/152933793046?hash=item239b907d16:m:meS570C_z-EvE71_T3eo5kQ:rk:36:pf:0&var=452699757422)
If not what low-heat led light could I safely use?
Thanks
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I'm planning to build a wooden & epoxy lamp similar to this https://www.pinterest.com/pin/71705819045683574/ (https://www.pinterest.com/pin/71705819045683574/)
There are tons of youtube videos of builds but no one mentions if heat of the light is a factor and I'm having a hard time figuring it out.
There won't be any holes in the wood for ventilation. Would something like this work to embed beneath the epoxy?
https://www.ebay.com/itm/Original-CREE-10W-XML-L2-Warm-White-LED-Chip-Base-For-Flashlight-Torch-Light/152933793046?hash=item239b907d16:m:meS570C_z-EvE71_T3eo5kQ:rk:36:pf:0&var=452699757422 (https://www.ebay.com/itm/Original-CREE-10W-XML-L2-Warm-White-LED-Chip-Base-For-Flashlight-Torch-Light/152933793046?hash=item239b907d16:m:meS570C_z-EvE71_T3eo5kQ:rk:36:pf:0&var=452699757422)
If not what low-heat led light could I safely use?
Thanks
I do not believe there is a safety issue because the Cree only dissipates 10 watts. However, if the resin does not move the heat away from the LED, it will kill itself over time. So success or failure depends in part on the thermal conductivity of the resin.
That is my SWAG at your question.
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I've seen plenty of wood light fixtures using old fashioned scorching hot incandescent lamps so you'll be fine. The LED will fail long before it approaches the char point of wood.
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Getting heat away from the LED is going to be a key factor for the long term survival of the LED. Even a 1W LED produces enough heat to self destruct in a relatively short time. You will need the LED mounted on a heatsink whatever you do. The LED you linked to is already mounted on a thermally conducting plate - but it really needs a way for the heat to escape. Mounting to a larger heatsink is usual - which is what the slots are for.
You don't necessarily need air flow inside the fixture, but it would be good if there was a way for the heat to be taken away from the LED. A big strip of metal to extend the heatsink mass will help and if it can find its way to the outside air, then that would be very beneficial. Perhaps you could make it a feature. If a large enough area in itself, it may not need to be finned - because that's all the fins do: increase the surface area to the ambient air.
You are spot on with asking this question, though. Heat is the number one issue with electronics.
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Thanks for the replies. I could surely incorporate a way for heat to get out/dissipate. I'll see what I can come up with.
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Run the LED at a lower voltage and its likely to stay much cooler and last a lot longer right there. Derating them a small amount makes a huge difference in their useful life span.