I like the Stay Brite and a more active flux.

I'd lay lengths of Stay Bright aside the joint, adhered with a fillet of flux,
and heat the whole job in the oven.

Preferably, you can block up the metal and support it flat, weight the tubing
into contact with fire bricks, and just heat soak it at the reccommended
liquidus using an oven thermometer to go maybe 15 degrees over so it won't take
forever. You can shield the work from the infrared of an electric oven to
prevent overheating.

The more active flux must be hand brushed with hot water until spotless, or it
will corrode.

You can pull the lengths of solder to straighten them, then snip and handle
carefully. You can also tack the ends of each to the tank before putting it all
into the oven.

I have and recommend The Aluminum Association's Aluminum Soldering Handbook.


Yours,

Doug Goncz ( ftp://users.aol.com/DGoncz/ )

Read about my physics project at NVCC:
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