LED Heatsink 10W?

[BigBrother]

I drilled and tapped the heatsink for M3 setscrews, and then used 1200grit waterpaper on a finishing block to smooth it off after relieving the threads around 0.5mm. Heatsink compound then used in a thin film between the 2 surfaces, and tighten the screws to the right torque.

The centre slug is aluminium, and the whole thing is an extrusion. Some have a copper pad fused to the base to improve thermal contact, but nothing there is terribly hard to drill. Very soft metal does bind the bit though, I always use cutting paste or oil on the drill bits, and a drill press. Better quality drills are also good, the ones that you buy cheap in a OHL store are not the best quality.

I didn't know the exact bolt size/name and (possibly) flung and obliterated one of the LEDs while trying to make a suitable hole. as for the heatsink... it's a VERY thick copper-like ally slug then. Seems like copper from the CPU contact point to under the fan to me! the ally is extruded but the copper feels milled/cut to size after being mashed in. (sorry if none of this makes sense, I'm tired)

[SeanB]

The manufacturer machines the recess for the copper heat spreader, then the spreader is either stir welded or pressed in to fit.Then the top and bottom are surface milled to make it smooth, and the cuts for the fan clips are cut in the side. This operation will leave residual stress in the copper slug, so it will need a press, as well as a sharp bit and a lubricant during drilling holes in it.

[M. András]

without coolant or a drill press the thick base of this extrusion what i bought for experimenting with leds are pretty hard to drill the tiny chips what the drill made are mostly stuck in the flutes and i couldnt remove them even by scrapping it. btw im proud of myself to make perfectly straight holes with a 18v skill coldress drill

[SeanB]

Coolant can be anything from plain oil, grease, cutting wax or soluble oil. In a pinch I have used liquid soap, butter or margarine and hand moisturiser. Basically anything that is either slippery or oily.

[M. András]

So what coolant do you use? How do you inject them? With a cordless ...

read pls before you post. i wrote without coolant

[SeanB]

All you need to have is a liquid that can transfer heat, and which can be carried to the cutting edge of the bit, while not boiling and not causing a build up of shavings. Even drilling in a pool of water works well enough, though it can be messy. If you are unlucky the cutting fluid will be your blood if you either have not held the workpiece with a holder, or it comes loose and whips around.

Working at an angle or upside down best is cutting paste or grease, as it will stick to the surface.

[BigBrother]

my current thoughts are that a 40mm ally cube with fins inside would be my best solution for the time. I could jam a 40mm fan on it and it'd work out... I hope. Can't think of what the right term for such a configuration of extrusion would be.

[BigBrother]

my current thoughts are that a 40mm ally cube with fins inside would be my best solution for the time. I could jam a 40mm fan on it and it'd work out... I hope. Can't think of what the right term for such a configuration of extrusion would be.

How about this? http://www.aliexpress.com/product-fm/505102468-1pc-10W-Watt-LED-Aluminium-Heatsink-Round-wholesalers.html
or this?
http://www.dealextreme.com/p/high-performance-dc-brushless-cooling-fan-for-for-pc-video-card-8946

I was thinking that with a hollow 40mm cube, I could attach a 40mm computer fan and have it blow through which would be enough for cooling. since it's a cube, the LED would be on one side, the fan blowing through the heatsink, some 15W AC DC ally-cased brick on the heatsink as well and I could rig the A19/E27 base for the socket. it'd probably be better if I had a diagram in 3D or the likes.

edit: the fins would likely be thinner or better spaced... or less fins but moreorless this:

the corner squares would be for screws and the misaligned huge, bulky lines going across the center would be the fins.

[BigBrother]

Basically, I'm looking for this:


but in a single piece alumun(i)um square tube with the fins inside so that no one part is heavy and it all has the same strength all around and it's 40mmx40mmx40mm.

[westfw]

"Fins inside" is not a very functional shape for a heatsink...  (All the radiative power of a solid block of metal, without the thermal conductivity!  Where were you going to attach the LED?)

The closest I see is apparently called a "corn bulb heatsink":
http://www.ivineng.com/upload/image/corn-bulb-heatsink%20led%20corn%20light%20extrusion%20aluminium%20heat%20radiator_lit.jpg

(of course, you could attach a "skin" to the outside of any extrusion with a regular outside profile, which is a lot of them...)

[westfw]

I gotta say that the whole LED lighting market has resulted in some pretty cool-looking heatsinks.  Almost artistic!

[BigBrother]

this is a generic aluminum heatsink:

Just imagine instead of the fins being in the open, it was closed. having 4 sides (or 3 minimum) would be needed so I could fashion the socket screw on it so I could actually use it like a bulb. If I can't manage to fashion the socket screw on the opposite side of the LED then it would have to be rigged with a lipped, round, hollow base to fit it in the cone's retention ring that would normally be around a light bulb. (this thing) the whole idea, again, of having the fins inside is so it's more compact, regardless of thermal dissipation- that's why the fan is there, to expel any retained heat.

[T4P]

If you want decent closed air heatsinking round spiral or circular heatsinks are best especially with a fan
The square ones are meant to have natural air flowing over it ...

[BigBrother]

while I was angrily pouting about being unable to find exactly what I want without custom ordering several meters and paying for cuts, I notice the a19/e27 base is a few millimeters smaller than the intel's fan's label! crazy, eh?





caution: bright red. for those who do not like red... I'm sorry.

I used seal-all quick-dry adhesive. it seems to have a really good bond between the screw base and fan housing.
Still no buck driver yet. Not sure where I could place it on this configuration...

Since I'm in an apologetic mood, I apologize to anyone who may have been offended by my earlier posts, if anyone was.  Some things have been going on when I made those posts that had placed me in a terrible mood.

[BigBrother]

I bought some of these, 10 to be exact and I thought they'd be a bit bigger... but I was wrong. they also want 20V. 

used a 3k resistor and awesome test... setup.

[BigBrother]

how do I tell if I cooked an LED? I finally got myself a heatgun and an MCPCB from led-mounting-bases.com but I have a feeling I cooked the LEDs... or botched the solder job somehow. ...it is ebay solder paste.

[M. András]

its pretty easy it wont light up or parts of the die wont light up as the die fried or the bond wires, killed an uv led this way what i tried to remount properly to the star pcb fried 1 of the dies from the 4 then killed another 2 with too much voltage from without current limitation last 1 still works but the brightness significantly reduced and its not good for the purpose what it meant to fulfill

[Psi]

Ok, i've not read this thread in a while but... Is that a large mains capacitor you're using for current limit so you can run the LED from the mains direct?
Interesting..

Edit: ahh, its just a holder, never mind. I thought you might be using a capacitor mains powersupply.

[T4P]

The dies are usually big enough for you to look through, any signs of heat damage (they are sensitive to heat!) will be clear, you can even see it on the phosphor(the plasticky thing on top of the die, for the XM-L it's very soft but careful not to damage them)
With such a massive nozzle it's easy to toast the LED, i think you should better go and grab a 858D instead.
Good for paint-stripping but hot air soldering NOT.