you can sweat solder 3/8" copper fittings to 1/2" soft copper tubing...I made an immersion chiller out of a 50', 1/2" soft copper (refrigerant) tubing (I sometimes boil 10 gallon batches in keggles so I needed a larger chiller). Instead of futzing with a tube bender, I just soldered 3/8" ell's...