Offset Bend in a Bar
Often offsets must be forged in hinges, door-bolt receptacles, wall
hangers & straps that join boards of different thickness and so on. to
forge an offset bend, proceed as follows:
Heat the portion of the bar to be offset to yellow hot and place the bar
on the cut-off table so that a portion overhangs the table. Fasten the
cold part to the anvil with a hold-down tool.
Place a set-hammer or flatter on the hot
overhanging part and using a 4-pound hammer, strike it with one or two
heavy blows. This offsets that portion accurately and simply. To increase
or decrease the amount of offset or jog, build up the anvil face or
cut-off table with plates of various thickness.
Another method of offsetting is to use a jig, as
illustrated, which allows you to shape the piece without using the anvil.
Clamp the jig in the vise. Hold the cold section of the bar with tongs and
place the hot part in the jig slot. Hammer successively each side of the
offset 90 degrees, flush against the jig's side, to complete the offset.
Next, reheat and true it up by squeezing the
whole assembly between the jaws of the vise ( assuming your vise is heavy
and strong enough to exert the needed pressure).
Still another way of offsetting is simply to
place the combined jig and heated bar, held together with Visegrip pliers,
on the anvil face, and hammer all down into proper alignment.
Bending an offset in a rod or bar can also be
quickly and easily done in specially made bending forks placed in the
anvil's hardy hole (see illustration) These forks are designed in a verity
of shapes to solve a wide range of bending problems. Heated sections of
rods and bars held in the appropriate fork can easily be twisted in this
system. But your anvil must be firmly bolted down on a well-anchored wood
stump or strong base and the fork must fit snugly in the hardy hole.
Additional tuning up is usually needed with hammer and anvil or in vise