Manufacture of Tinned Ware
As tin will not adhere to the steel unless the surface is perfectly free from
dirt, the steel is subjected to a long cleaning process.
It is first immersed in hot, dilute sulphuric acid and
then washed, heated, and passed through polished iron rollers to give it a
well-polished surface; it is annealed again, immersed once more in dilute sulphuric
acid, re-washed, and scoured with sand. At the end of this process the sheet
is clean and bright.
Next, each sheet is put into a pot of melted tallow, where it is left until
it is completely coated. After this the plates are plunged into a bath of melted
tin, in which they remain from three to five minutes.
After cooling they are polished with bran.
The best tin plate is dipped twice; this is called "block tin", or "retinned
ware".
The articles are drawn on dies or seamed from "blanks" (see Cutting Dies).
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