Heatsink soldering/baking procedure

[triturbo]

I'm thinking about making my own heatsink and I think there was a topic, or at least a post about it, but I can't seem to find it. Maybe it was on a forum long lost? It would be nice if the knowledge can be summarized in one post, like it used to be. Thanks!

[GuitarG]

Most important ? Use low temp. soldering paste - lowest is Sn42/Bi58 Melting Point: 139°С. (I'm  pretty sure manufacturers use this exact compound).
Also best to use something like oven with temp. control - don't exceed 140-145 celsius degrees for both heatsink dissasembly and reassembly. And oven is best because of heatsink properties, you need to saturate (heat) every heatsink part for solder to melt and not damage fragile heatpipes.
Best way to clean old solder or prepare surface for soldering is to sand down using sand paper or flat metal file and wipe with isopropyl alcohol on tissue.
Make sure surfaces are flat as possible for best contact between surfaces. Solder is for mitigating air gaps and holding both surfaces. 

[Khenglish]

Toaster oven is best for soldering and desoldering. It's also good for cleaning off solder after disassembly. Just rub a paper towel on the heat pipes when the solder is wet. You just need to smooth out the old solder. No need to try removing it all.

 

When resoldering I find binder clips work well for pressure. Don't apply too much force with something like a vice or C-clamp. Heatpipes will crush in the middle, greatly impairing their function.

 

Heatpipes will start to expand over 145C. This can be helpful if you do accidentally partially crush one to restore it. They pop at around 210C.

 

Bending heatpipes without kinking them is very difficult. It's best to bend them when they're soldered to something to help keep them in shape. If they are unsoldered, it can also help to loosely fit them into a vice to prevent kinking. If they are already flattened you can't use a pipe bender, but you can use a bender if they are new and unflattened. I typically reuse flattened heatpipes.

 

No added flux is necessary. Whatever the paste has is fine.

[triturbo]

Thank you very much guys!