one of my clients found a Ted Williams lantern in very rough shape-- he had the vent re coated with enamel by IPE and asked me to save the font. the nickel was nasty so I stripped and renickeled, but the challenge was the rusted out steel bottom of the font. Soaked the font in Evaporust for 48 hours-- gave it a coat of tin== took the bottom of a donor font from a lantern that had to many issues to save. tinned and soldered the bottom of that- laid it in place-- heated until solder flowed to make the joint-- made an air-tite seal but as always with this type of repair I give it a Caswell Tank Sealer treatment--