Bob, I wouldn't worry too much about the boiler, it has a pretty good safety-margin. I made mine, my first ever boiler. When I hydraulic tested it I misread my gauge, and took it up to 300psi instead of the 30 I was aiming for… Apart from a slightly distorted top it survived the experience, and has given good service ever since.
Edited By Bob Unitt 1 on 23/03/2020 14:20:23