You have to Solder wires BEFORE on the heatsink otherwise it pulls the heat away. like it should .
Well, that's one explanation....
Were you high when you wrote that? bongsmilie
Do not be taken in by the "green light is not used myth"
Better, but 63/37 is ideal. It has the lowest melt temp and no plastic state. Make sure the core is rosin flux and not acid flux. Acid...
Watts are not relevant - only the current going through the wire is relevant to wire size choice.
Forget that lead free shit, it is a total pain in the ass to use. Get some 63/37 tin/lead rosin core solder.
Why on earth would you be using 4 AWG? That's rated for like 100 amps.... all you need is 18 AWG.
Yes, regular extension cords will work.
The ground is not needed for operation, but is necessary for safety. Power cord from a computer power supply will be plenty big enough....
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