I did mention this many pages back, but it is worth saying again. You can use a standard mapp gas bottle with a regular torch (no oxygen), and use the 56% Ag solder to braze brass to stainless or stainless to stainless. I'm talking about sanke keg type thicknesses and regular brass or stainless nipples. It's MUCH easier than messing about with flaring, soft solder, and the liquid flux. Not only that, but the joint will be stronger. The paste flux (such as handy flux) is much easier to deal with than the liquid HCl flux. I'm all for making the most of Home Depot stuff to get by with brewing stuff, but when you have a thread this long, with people trying all sorts of measures JUST to make a nipple securely attached to a keg with soft solder, why not just get a bottle of mapp and some 56% Ag and be done with it? You don't have to learn to TIG or oxyacetylene, and you can still call it diy (no paying welders), and it's just better than using 4% Ag soft solder.