Copper and a Gloabwin?

[Daedlus]

I'm looking to improve the cooling capabilities of the heatsink that I have. I have looked at picking up an all copper gloabalwin, but I was thinking that I could just solder a copper plate to the bottom of my current HS. I have no soldering iron, and I want as much contact as possible, so I was thinking of cutting the plate to size (large enough to use the mounting holes on my A7V133 instead of clips), and then heating the bugger up on the stovetop, and then just applying the solder to the join that way. Any advice (first time)?

Just to give an Idea, I have a Gloabwin on the board now, and my T-bird is cooking at 52C

 

[outhouse]

its not a bad idea and i love tweaking and making my own mods but this time I think your better off getting an all copper HSF as thats the whole idea of copper that it dissipates heat better and this is also true for the cooling fins of the all copper HSF. Copper cooling fins are better then aluminum ones.

 

[Kryten]

outhouse (May 20, 2001 05:14 p.m.):
its not a bad idea and i love tweaking and making my own mods but this time I think your better off getting an all copper HSF as thats the whole idea of copper that it dissipates heat better and this is also true for the cooling fins of the all copper HSF. Copper cooling fins are better then aluminum ones.

I agree with outhouse all copper will cool better, BTW some globalwin already have the copper base attached to the ally HS, maybe you could try your attachment method on a copper one?

 

[Megahurtz]

Pop for the Cak-38, and experiment with older stuff. I too like to hack up hardware, but unless you can silver solder..completely with almost absolute perfection, you're likely to hinder cooling.

I think that two correctly lapped surfaces..mechanically fastened together ala Noise Control Silverado would be more feasible, and may yield better results.

T

 

[William]

when you start to heat copper, it starts to oxidize, ruining its capibilities. Just go for the CAK38, its not too expensive, and will give better results. But, if you do this we want pictures and results. I shall be very interested if you do this!

 

[Daedlus]

Okay,I've decided to start nice and easy.

I'm going to attach an aluminum foot to a KWi Platinum (Clone of a thermaltake). I've yanked the mounting clip and the plate of aluminum that held it on. I'm going to grind an lap the foot until smooth, and then heat the footplate, put the KWi on top where I want to make the weld, and then depend on capillary action to get the solder where it needs to go.

I am doing all of this as an experiment, as my T-Bird is currently cooking at 52c. I'll post some pics if I can get a hold of a camera.

 

[Hoot]

Forgive me for not understanding you intentions completely, but are you going to try to solder copper to aluminum? What solder are you going to use to accomplish this?

Hoot

 

[Daedlus]

I must admit, it has been about 12 years since I have even touched a soldering iron.

Is copper not compatible with aluminum? I know that they have a different melting point, but that seems moot, as all I need to do is heat the plates up until the solder melts. I would be using flux to prep the plates.

I have seen other posts that seem to suggest the use of thermal epoxy as the joining material. For sure it is easier to work with, but does it interfere with thermal transfer between the things it connects?

 

[Hoot]

Okay, I did understand you right. As far as I know, there is no solder that will bond with aluminum and copper. There is aluminum solder, such as "Wonder Rod" and there are plenty of solders for copper, but never the twains shall meet. Bonding the two surfaces together with a thermal epoxy, such as Arctic Silver Epoxy is about as good as you will be able to do. With enough clamping pressure, you should be able to get the interface barrier down to a minimum, but it will still represent a thermally resistive junction between the two metals. Don't get me wrong, that is a common procedure for copper base heatsinks with aluminun fins. As a matter of fact, most dual metal heatsinks do not use any thermal interface material. They just clamp the two together and rivet them, screw them, or rely on the friction of a press fit. The bottom line is, even though it would make for an excellent project, it won't "Set the world on fire" in terms of performance. I, myself, have taken an all aluminum heatsink (FOP-32) and merged it with a 1/4 inch copper plate on the bottom. The copper plate, being almost twice as thermally conductive as aluminum, helps spread the heat across the entire baseplate. The best improvement I ever obtained was on the order of 2C. I'd say the best performance comes from an all copper HSF, followed distantly by a dual metal and then an all aluminum. Forget silver. It's just not that much better than copper to warrant the additional cost and difficulty obtaining machining stock.

Hoot