What I did though was to braze the brass ferule to the stainless insert. The ridged insert that takes the big bung just happened to be an exact match for the 2 inch brass ferrule. I brazed it with 55% silver solder. It is not as pretty a joint as I wanted but it took a lot of heat even with my biggest propane torch.

It is a very solid joint though.
The other joint was the 1.5 inch ferrule that I fitted where the tap goes on the cask. This is for a 5.5 kW element.
I was pleased with that joint. I forced a bit of 35 mm copper tube into a 1.5"/38 mm stainless ferrule. The inside bore of the ferrule is 35 mm so it was an exceptionally tight fit. I then soldered the copper tube to the ferrule with cupalloy 2207. This is a 4% silver solder specifically for soldering stainless steel. Then I hammered the short bit of copper tube into the tap bung on the cask and when the ferrule was flush with the stainless flange on the cask I soldered them together just to make sure.
That joint would probably be leak free without solder but it is absolutely leak free now.
The brewbuilder element passes through the 35 mm tube with ease.Statistics: Posted by Myles — Thu Feb 08, 2018 7:39 am
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