Pickle saved the day! Following my misshap with the steel washer in the old pickle (see comment on previous post) a further week in fresh pickle reversed the copper deposition.
Also the silver solder finally flowed. The improvement was down to using more flux and using a bigger burner to get the temperature up quicker.
The finished job may look a little messy to the more experienced practitioners out there, but to me it looks lovely as it’s my first sucessful boiler build 🙂
Now I like to say it held pressure on its first test, but that would be a fib. Two of the bushes leaked when I tested it initially at 10 psi immersed in a bucket of water. The answer? MORE SOLDER.
It has now been tested to 30 psi and not so much as a nano bubble escaped – phew