Just picked up this 413E. Finally a copper tank! Here it is next to the 425b that I'm reconditioning. We used this stove throughout my childhood and most of my adult life and I had no idea how really small it was!
True, but they may be copper braised. When I was cleaning the mixing chamber I discovered copper on the seam. And yeah, My 425b tank has a lot of the copper paint worn off to the steel.
My 425 has the Everdure tank circa 1940-1945 still in very mintish condition. Those tanks are great! Ron