The manufacture of
auger bits is one of the oldest of the tool
industries in this country.
Great Planes Trading Company
Many of the factories have remained in the families of
their founders for generations and, as is usual in such
cases, radical improvements in either the product or the
processes of manufacture have been slow. The bit
described in this article has been improved, not by
adding anything to it but by taking something from it.
Some of the processes in its manufacture are different
from those generally used in bit making. Boring is only
whittling in a circle and just as one uses only one
blade with which to whittle so it is only necessary to
have one cutting blade on an auger bit. Likewise, it is
only necessary to have one scoring lip to cut off the
The steel used in the auger bits made by the W. A. Ives
Manufacturing Co., Wallingford, Conn., is made to its
own specifications using genuine Swedish pig as a base.
It has a slightly higher content of manganese than of
carbon, to give stiffness; while for the endurance of
cutting edges, a trace of tungsten is added.
The blanks for the bits are sheared from a flat bar of
suitable size, and after being heated the shanks are
drawn out and the squares formed in dies in high-speed
Bradley hammers as may be seen in Fig. 1.
Fig. 1 – Forging the shank.
Next, the blade is die forged in the same type of
hammer. In this operation, known as plating, the blade
is left thicker at the center than at the edges, the
shape being similar to that of a slitting or
This shape is not carried out to the extreme end, a
blank space about twice as long as the width of the
blade being left for drop forging the leader-screw blank
and scoring lip and to leave enough thickness of metal
for forming the cutting lip.
The appearance of this end after drop forging may be
seen in Fig. 2, in which A is the blank for the leader
screw, B the scoring lip and C the part from which the
cutting lip is upset.
Fig. 2 - The drop-forged head.
It will be noted that an unusually large flash is left
from the drop-forging operation. This is to ensure the
maximum compression of metal at the vital part of the
bit and to make certain that any accidental overheating
of the metal at the edges and the extreme end will not
affect the cutting parts. Trimming off the flash is done
in an ordinary punching machine provided with suitable
The appearance of the bit blank after it has gone
through the operations described is shown in Fig. 3.
Fig. 3 - Operation before twisting.
A is the blank as cut off by the shears; B has the shank
drawn out and the square formed; C shows the blade after
plating. Here the thickened center and the flat at the
end left for drop-forging may be seen. D shows the
result of the drop-forging operation, and E represents
the appearance after the flash has been trimmed.