Tinning is a crystalline, silvery metallic element obtained chiefly from cassiterite and having two notable allotropic forms. It is the process of thinly coating sheets of wrought iron or steel with tin, and the resulting product is known as tinplate. Tin is a metallic element, occurring in cassiterite, that has several allotropes; the ordinary malleable silvery-white metal slowly changes below 13.2°C to a grey powder. The term is also widely used for the different processes of coating a metal with solder before soldering. The proper use and care of the soldering tip will increase soldering production and decrease solder joint failure.
Tinning the tip means covering the tip with a layer of solder. It is most often used to prevent rust, but is also commonly applied to the ends of stranded wire used as electrical conductors to prevent oxidation, and to keep them from fraying or unraveling when used in various wire connectors like twist-ons, binding posts, or terminal blocks, where stray strands can cause a short circuit. Most modern soldering tips are composed of a copper core (copper conducts heat excellently) encased with nickel-plated iron to repel solder.
While once more widely used, the primary use of tinplate now is the manufacture of tin cans. Tinning the tip extends the life of the tip by preventing oxidation and corrosion, but it also causes the solder wire to melt and flow more easily over the parts you are joining, making the overall soldering process go smoothly. Formerly, tinplate was used for cheap pots, pans, and other holloware. It is used extensively in alloys, esp bronze and pewter, and as a noncorroding coating for steel. This kind of holloware was also known as tinware and the people who made it were tinplate workers.
Tinning is the act or technique of coating with tin. The untinned sheets employed in the manufacture are known as black plates. A major application for tin is in tinplate for food canning. They are now made of steel, either Bessemer steel or open-hearth. The old hot-dipping method is little used, having been replaced by continuous electrolytic tinning of sheet steel.
Tinplate was consumed in enormous quantities for the manufacture of the tin cans in which preserved meat, fish, fruit, biscuits, cigarettes, and numerous other products are packed, and also for the household utensils of various kinds made by the tinsmith. It is the application of a thin layer of soft solder to the ends of wires before soldering them.
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