How to make a copper heatsink without a lathe, as shown on SMALL SUN ZY-C10-S Aspheric *BEAMSHOTS ADDED* STOCK vs XM-L

LED Flashlights ā€“ General Info 18650 Flashlights
1

I recently received this light from Manafont:

http://www.manafont.com/product_info.php/small-sun-zyc10s-cree-q5-3mode-floodtothrow-led-flashlight-black-18650-p-8459

This aspheric-lens sporting thrower is a monster in stock form. It draws 1.46A at the tailcap on HI, which is quite a bit for the stock XR-E (EZ100 die.)

After my unfortunate discovery of the paper-thin heatsink on the UF-V4`recently, I wanted to peer inside this hard-driven light. SURPRISE ! There's a hollow pill !!!

Weighing in at a staggering 10 grams, the pill's lack of thermal mass will guarantee a dead XR-E soon enough.

Don't own a lathe? Here's a solution:

Next to the pill is a length of thick copper bare wire (~4.5mm), sourced at a local DIY retail store. (Menards)

I measured the interior dimensions of the pill, then cut the wire pieces slightly shorter to allow driver component clearance.

After a bit of sanding, the test fit revealed a nice symmetry.

I chose to use the setup as-is, without filling the gaps with smaller wire for simplicity's sake. You may choose to do so.

Below, you can see the original wire pass through holes:

After liberal application of Arctic Silver and overnight curing, this is the result:

I rolled silicone-infused parchment paper over tiny mandrels (toothpicks) to maintain the wire pass-through. After removal:

Next, comes the new emitter and driver. You may choose to re-use the originals, safe in the knowledge that you have a copper-cored pill that now weighs 39 grams !!


This method will work on most hollow pills, so have fun.



2

The KD 3040mA driver was electrically isolated with a new (to me) product. It's an enamel spray that is used to touch up motor windings or bare wire.

Next, the driver and LED installation.

3

Smart idea! I like how it turned out. Just a bit concerned how well it does transfer heat to the aluminum pill. There is still some room for improvement i guess. Perhaps using AS to stick the edges onto the pill would have an improved effect.

4

Chicago X, thanks for sharing.

Another possibility, if you don't have Arctic Silver kicking around, is to load the pill up with copper and solder. I did it on the stovetop, in a saucepan. (Key hint to those that want to maintain good relations with their spouse -- line the whole saucepan with aluminum foil, so the flux splatters don't make permanent marks. Don't ask me how I know.)

One problem is that the surface tension of the solder tends to make a big ball, rather than a nice flat surface, so I dropped in a copper disk and let the excess solder flow over the edge while pushing the copper down and letting it cool. I ended up re-heating it (but you could probably do it in one step) and then slurping up the excess solder with a solder sucker. A little bit of finishing with a sharp chisel and sandpaper, and I had a tidy flat surface to mount an emitter on.

5

great idea - I'll be trying some variation of this soon. this light is really a must have if you like zoomies.

6

Nice job!

I did something very similar using a copper end cap from the hardware store and filling it with copper wire as well. I went one step further and filled the gaps with solder. It's one helluva chunk of copper/solder. I've had it sitting around for a while, but think I've come up with a great mod for it.

Details to follow....

7

Good idea, but if you feel that is a bad dissipated light, most other zoomies are worse than that, many have the led star "in the air" being in contact with metal just on the edges.

8

I'm not certain about the temperature range that would be encountered on a heat sink, but I'm curious about filling a pill with something like Wood's metal or a similar alloy for additional heat sinking...

Wood's metal has a melting point of 70oC/158oF. Other similiar alloys can be found with higher/lower melting temperatures.

9

There is a TON of Arctic Silver inside, adhering the copper to the flat disc of metal upon which the emitter rests. Each piece of Cu was coated to ensure good heat transfer to the next piece. The AS you see on the surface is not necessary, as it is a result of the epoxy being pushed out of the pill.

As others have mentioned, solder also works well. I use a liberal application of flux to ensure solder penetration, and have had little problem with solder migration doing so.

10

What about using Alumiweld? JohnnyMac gave me the idea of filling a pill with Alumiweld in another thread. For those in the US, Alumiweld is available at Harbor Freight. I'm not sure how it turns out cost-wise.

-Garry

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their page states the thermal conductivity - ~40% of aluminum's

cost isn't bad - about double what I paid for silver bearing solder at home depot

I've been thinking about buying copper powder and mixing it w/ solder paste

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Even better, why not use the best of both worlds? Personally I like Eā€™s idea of packing it with copper wire. Pack it tight enough then heat it with a torch and fill all the air space with solder or Alumiweld. Solid pill with better thermal conduction than pressing in thermal paste/epoxy. Just redrill the holes for the wiring to pass through.

13

Aluminum repair rods won't work for that, used like that. You'd have to fill the hole with molten rods, then dip copper into it. Not a big problem, I'd guss, but it can't be done the other way around, like suggested.

Molten aluminum repair rods have EXTREME surface tension. See video.

http://www.youtube.com/watch?v=w2rlkfhhQs8&feature=related

Viktor

14

How about running wires first and tamping aluminum/copper foil in the void?

15

I would be afraid of air pockets with that method.

16

The purpose of the thread was to show a method that could be done without lathe or fire.

With a torch, the copper+solder method works well (as others have noted, above):

Before on the right, after on the left. :)

17

Thanks Chicago X! Thanks to you I had to swing by Lowes Home Depot on my way home from work and pick up 4' of #4 AWG solid copper wire! You're such a bad influence on me! Such an encourager/enabler!

-Garry

(Just kidding of course, and I'm truly thankful for the idea!)

18

I was certain of the purpose, since you OWN a freaking lathe ;)

I might add - a vise or at least vise grips. Alternatively, I guess you could set it on a stone or something (to melt in solder).

I did try a making 'coil of foil' (copper) and you can get most of the air out (w/ a hammer and vise!), but it is expensive and labor intensive vs. heavy gauge wire like Chicago_X did...

19

Update in the first reply.

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I just found another reason for using this method - a pill that can't be removed from a light (and you don't want to turn the light orange :) )