[Illustration]
The simplest problem for a first weld is a flat iron
ring. This drawing shows a ring 3 ins. in diameter on the inside and 5
ins. on the outside.
_Stock:_ Flat piece of iron 13-1/2 × 1 × 3/16 ins.
_Directions:_ The making of this ring involves the processes of
bending and welding. Before the bending is done the two ends are upset
and made about 1-1/16 in. thicker than they were, for about 1 in.
back from either end. To do the upsetting, place the hot end on the
anvil vertically and strike on the cold end with the hammer until the
required thickness is obtained. If the end which is being upset was not
heated more than 1-1/2 in., it will probably upset without bending. If
heated more than this the probabilities are that it will bend during
the process. If it does so, it should be laid upon the anvil and the
bend hammered out. When the desired thickness has been obtained scarf
the ends as shown in the drawing, using the round end or peen of the
hammer to do so. (See scarfing.)
Do the same to the other end, putting the scarf on the opposite side to
the first one. Now heat the piece, about half its length, quite hot.
Place it upon the thickest part of the horn of the anvil, strike upon
the end that projects beyond the anvil, and bend it into a ring. The
scarfs, being opposite, will now fit and come together. (See drawing.)
Bend over till the two edges lap. This gives plenty of material where
the joint comes, to allow for the waste of the material from the high
welding heat and also that needed for the hammering of the metal during
the welding. The upsetting is done to allow for this waste, and to
give opportunity to reduce the pieces to the required thickness. All
welds should be a trifle large at the joint. The driving down edgewise
on the horn of the anvil bends the material, but prevents one shaping
it to its proper dimensions. That is why in flattening down the weld
care must be taken not to widen the iron at that place so that it is
too thin. A few trials will make this perfectly clear. A finish on the
iron depends upon how skilfully one can use the hammer without unduly
marking the metal.