My dad used that stuff back in the 1940s the tin was bought in the 1930s like yours. He built several radios and lots of electrical gadgetry using the same iron you describe, an 'ingot' of copper on a steel rod, 2 mins in a gas jet and it solderd anything . I could never get it to work!!Glengrant said:Ah, found my uncle's soldering flux. I was wrong about the Fryolux Soldapaste, that's much more modern stuff. No the stuff he used was "Fluxite" as shown here. During the war he built ships, and if he used this stuff and his red hot iron, those ships will still be afloat.
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