Courui Big Head COPPER heat sink feeler. Let me hear your voice!

OK guys here is the latest. I shopped around on Etsy ( thanks for the link TomE) and found a seller who wills stamp us some relatively thick copper discs.

I asked if we could get 41mm diameter in a 12 gauge thickness.

The reason I asked for the 12G is its almost exactly the same thickness of the factory plate which we know has been proven to be the correct height with an MCPCB still on top of it. I belive copper in 12G should be .108" thick and the full thickness of the factory plate is .116"

I asked for the 41mm diameter because this is just narrow enough to pass the threads on the neck of the light.

My theory on it is that once it sits at the bottom there will be just enough play to get the emitter perfectly centered. This way we can reflow the MCPCBs to the sink for a direct thermal path.

Then we can just use the camera rings to hold the sink in. Best of all this means NO Twisting of the wires.



I have PM'd the seller to make sure about the true measurement of the 12G copper. I inqured about only 10 pieces and was able to get the special size. I will also ask if she will make an open listing on the site so if others are interested they can purchase. If they dont want to list them as singles I will order extra for other interested people.

Right now it looks like the cost per piece would be only about $2.50-$3.50 plus shipping.

What do you guys think?


Sounds good to me, that way people can choose wether or not to add any extra heatsinking on the back of the disc - if it’s ever needed.
At that thickness it would be fairly easily heated up with a torch and you could solder any extra copper lumps/sinks directly to it.
Plus it would keep the postage right down for international orders (like me :slight_smile: )
Oh, and here’s a photo of it screwed in (the ring) - and I don’t want to hear ANY comments about the duct tape…… :smiley:

Think we can also order smaller ones to add to the underside?

Sure, I dont see any reason why not. Personally I'm not really sure that is going to add any measurable amount of sinking. The walls of the neck of this light have really got some mass to them. I think the lightning quick transfer of the copper MCPCB and the plate are going to what is needed.

If gaining mass is something people are still interested in I can still offer the #4 option aluminum sink. I would think the larger aluminum sink or just the copper plate would be the 2 best options both for cost and effectiveness and function.

$2.50-$3.50 plus shipping??

Copper disk all the way!!

I just ordered a 10 pack and with shipping the cost was like $29.94.

I have asked her to make a public listing for the group. I also double checked to make sure the thickness was correct. She said they are 2.8mm thick ( .110").

If she puts it up so individual discs can be purchased I will post a link ( I cant imagine why she would not).

Sounds good.

What about an addidional chunk for the underside?
Should be around 34mm in diameter and 10mm high?

Ok, I heard back from the Etsy seller I mentioned. We seem to be having some communication issues, but I was able to get listings posted.

The batch I purchased was just under $30 for a ten pack. I asked here to make a listing so everyone else can purchase as well and she reposted the listing I got.

So I guess if anyone wants a ten pack here it is.

This item is unavailable - Etsy


I asked again if we could get an individual listing for them and she said we could. There is a quantity selection for multiple items but no break in price for buying extra this way :(

This item is unavailable - Etsy



If neither of these options is suitable I would be willing to make another order for the group in enough people want them.

How stupid am I??? I just took a look at those copper discs….for some reason I imagined they were parted off from a bar - I now see they are laser cut or punched out - I work right next door to a sheet metal factory! it didn’t even cross my mind.
Monday I’m going to see someone to see if it would be possible to make a few (or more). No promises. :wink: The good thing about working in an electrical wholesalers is you meet loads of people - I’m getting a bit matey with a guy from the anodising place over the road at the moment - if that works out happy days!

:arrow:

Cool! That's Laura on Etsy, who O-L has dealt with in the past. She's got a pretty good story for her biz in a very poor area of Mexico - helping local women make a living. O-L bought a supply of the larger size copper discs for heat sinks a while back, mostly in SRK's I believe.

Qty 4 for $10 is pretty good!

LOL. Sorry man. I've had to quote myself a time or two as well..

The 34mm diameter part should be no problem, its just that these pieces are stamped out of sheet metal so there is probly some limit to the thickness we can get. You could shoot her a message and see what the max thickness is. She did tell me at one point 10G would be no problem so who knows perhaps they can.

Here is chart to give an idea of the gauge thickness.

http://www.unc.edu/~rowlett/units/scales/sheetmetal.html


There is no measure that thick on the chart, but I am guessing if it exists you'd be looking for 000 or 0000 G to get a nearly .400" piece?




EDIT: MY bad all. Dont buy those copper discs I linked unless you have a lathe. The diameter is perfect but they are NOT flat. They have about the shape of a convex lens.

I was able to machine a flat surface for mounting the led to the top, and there is about a 1/16" lip on the bottom that is flat to transfer the heat to the neck.

If any one would like one of these with the top machined flat, I would sell them for $5 each with $2 US shipping and $6 world wide.

Again I do apologize I did not know those would be convex.


Haha….would you take a trade in? I received those discs last week. :stuck_out_tongue:

Oh boy.. I'm having similar problems from my regular source on Etsy, the "bopper". The copper rounds are typically convex like you describe (bump in on one side, bump out on the other). I would think maybe you could hammer them flat if you have a good setup for that? Hard, flat surface? Maybe the hammering though would creat more unevenness than you begin with? I've been sanding but it's tough to get them completely flat. A super vise maybe would do it for the small thinner ones?

Have you been assembled a courui with good results with the machined copper? Is it hard to focus? How does it work?

If it works I would gladly take one or two of the heatsinks.

Maybe sand the convex side a bit to get a good mm or 3mm wide contact patch and then solder a star on the convex side? Is it that bowed?

Sure I will work with you on that. Shoot me a pm with your offer.



I also attempted the hammer flat thing as I thought it would be best, but the disc size is so tight already that when you flatten it it becomes too large to get past the threads.



I have not had the opportunity yet. I actually sold both of the couruis I had. They sit "roughly" the height of the factory pill when its flipped over which was not hard to focus, so I'm thinking a little bit of tweaking is all that is needed.



Ya the bow is significant. Factory total height is 4.61mm and with a spot flattened wide enough to use the maxtoch 32mm mcpcb the height is 3.58mm. Just flattening a small area and trying to fill the gap in that bow with solder would be some trick :)

In related news, I need some copper for a pedestal to raise up a MCPCB to the height needed to focus well in a reflector made for a halogen bulb. I need somewhere between 1/2” to 3/4” total thickness I think. I’ll know when I put it together. The light is a cheapie spotlight with a 8” wide reflector, so extra width won’t hurt. The reason I’m posting this here is because I was thinking maybe someone would like to relieve themselves of some of these discs, and I could sandwich them together with solder. I’ll hammer them flat first, and sand it down smooth after soldering. I’d be happy to take several off your hands, because I could probably use them again sometime.

Meanwhile, if you have a bench grinder, a belt sander, or Dremel-style rotary tool and you’re determined to use these for what you bought them for, you could probably pound them flat and then grind the excess off from around the edges to make them still fit in the Courui.