While standing on this
heavy piece the metal may be upset by striking down on the end with a heavy
hammer or the sledge. If a bend appears while upsetting, it should be
straightened by hammering back into shape on the anvil face.
Light blows affect the metal for only a short distance from the point of
striking, but heavy blows tend to swell the metal more equally through its
entire length. In driving rivets that should fill the holes, heavy blows
should be struck, but to shape the end of a rivet or to make a head on a
rod, light blows should be used.
The part of the piece that is heated most will upset the most.
To punch a hole through metal, use a tool steel punch with its end slightly
tapering to a size a little smaller than the hole to be punched. The end of
the punch must be square across and never pointed or rounded.
First drive the punch part way through from one side and then turn the work
over. When you turn it over, notice where the bulge appears and in that way
locate the hole and drive the punch through from the second side. This
makes a cleaner and more even hole than to drive completely through from
one side. When the punch is driven in from the second side, the place to be
punched through should be laid over the spud hole in the tail of the anvil
and the piece driven out of the work.
Work when hot is larger than it will be after cooling. This must be
remembered when fitting parts or trouble will result.
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