*CANNING IN TIN cont'd
After exhausting, the cans are removed from the sterilizer and the vent
hold is closed. The cans are returned to the sterilizer and sterilized,
following the time-table given on page 2. At
the end of the sterilization period remove cans and plunge immediately into
cold water. Do not stack cans closely until cold.
After packing, label each can by writing the name of
contents on the side. If intended for sale affix a label just before
shipping. Do not allow paste to touch the can, as it will cause the tin to
rust. The label should be large enough to encircle the can and overlap at
the edges. Put the paste on one of the overlapping edges and draw label
tightly around can, pasting the two edges together.
To seal, wipe top of can clean and dry and then put the cap
in place, applying flux carefully to the groove. Do not allow the flux to
enter can, as it is poisonous. Hold the cap in place with the center rod and
lower the hot capping iron squarely and firmly on the solder rim of the cap,
or melt a little solder in the groove by holding the solder wire against the
lower part of the capping steel.
Revolve the iron to melt the solder and seal the can. Lift the capping iron
wit a sudden twist, holding the center rod in place. When solder has
hardened remove center rod.
To tip, dry top of can and apply flux to the hole in the
center of the cap. Hold the solder in the left hand, brush it with the hot
tipping iron so only a bead will drop and close hole.
The steels must be kept clean and well coated with solder. To do
this, if capping steel is rusty, clean with a file, brick or emery paper. To
tin the capping steel heat and dip in flux, then heat again until red hot
and dip in sal ammoniac and solder until well coated. Sal ammoniac is made
by mixing equal parts of dry sal ammoniac with solder chips. Coat the
tipping copper in same way.
Flux is made as follows: To muriatic acid add strips of zinc until
no more will dissolve. Strain through a cloth and when ready to use add an
equal quantity of water. Flux which is used for tinning the tools should not
be used for soldering.