Soldering Aluminium Sheet 3mm Thick

Soldering Aluminium Sheet 3mm Thick

Grade/Spec: 1050A H14 - a commercial purity alloy giving excellent corrosion resistance. It is Ideal for welding, bending and moulding. It is also suitable for painting.

I have a sheet of this aluminium sheet, roughly 50cm x 40cm

I want to try soldering one of these LEDs http://www.ebay.co.uk/itm/161109303192 to it, hopefully via 4 small dots of solder one dot in each corner.. after putting a little heatsink compound behind the LED

I understand a pre-clean with stainless steel wire wool, and the use of a fairly harsh acidic flux may be neccessary along with a very specific grade of solder.. but most sites talk also about preheating the aluminium with a gas torch.. I'm a little worried about damaging the LED with too much heat.

Could a fairly decent high power electric iron with moderate preheating of the aluminium do the job? I guess pre-tinning of the aluminium sheet at the 4 target points too?

The safe alternative would be to drill and tap the aluminium sheet and affix the LED with small screws, but this would spoil the appearance of the reverse side of the sheet and that's something I'm trying to avoid.

Alternatively, anybody have any good ideas for securely affixing one of these LEDs to the aluminium sheet, ensuring good heat transfer, without the use of solder? Does something like a good double sided sticky back heat conductive heatsink tape exist?

I saw for instance http://www.ebay.co.uk/itm/350933892948 which looks great but, firstly I don't know how sticky its would be or how long lived, and secondly the listing does hedge it's bets a bit saying that if you used it for a CPU, you'd fry it. So I don't know how good it'd actually be, had no experience of it.

They talk about "thermal epoxy"? http://www.ebay.co.uk/itm/271180279856 ?

The whole shebang is going to become a lid for a fishtank.

That's it, finished editing.. sorry about all the changes if you were reading whilst I was half answering my own question. Advice from the experienced still very much sought & appreciated.

 

This guy makes a nice job of it but, he's using more of an open flame than I'd be comfy with



Shows it's possible though

bit more info

http://www.superiorflux.com/aluminum_soldering_flux.html
http://www.superiorflux.com/aluminum_flux_cored_wire.html

I'm kinda intrigued about the arctic silver epoxy. Would that stick well to the ally?