and pneumatic hammer riveting methods. Rivet sets are
Ball peen hammers are made in different weights,
available to fit every size and shape of rivet head. The
usually 4, 6, 8, and 12 ounces and 1, 1 1/2, and
ordinary handset is made of 1/2-inch diameter carbon
2 pounds. For most work, a 1 1/2-pound and a 12-ounce
steel about 6 inches long. It is knurled to prevent
hammer will suffice.
slipping in the hand. Only the face of the set is hardened
MALLETS.--A mallet is a soft-faced hammer.
and polished. Sets for the oval-head rivets (universal,
Mallets are constructed with heads made of brass, lead,
round, and brazier) are recessed (or cupped) to fit the
tightly rolled strips of rawhide, plastic, or plastic with a
rivet head. When you select a rivet set, be sure that it
lead core for added weight.
will provide the proper clearance between the set and
A plastic mallet, similar to the one shown in figure
the sides of the rivet head and between the surfaces of
4-1, is the type normally found in the AM's toolbox.
the metal and the set. Flush or flat sets are used for
The weight of the plastic head may range from a few
countersunk and flat-head rivets. To set flush rivets
ounces to a few pounds; however, the size of the plastic
properly, the flush sets should be at least 1 inch in
mallet is measured across the diameter of the face. The
diameter.
plastic mallet may be used for straightening thin sheet
Special sets, called "draw" sets, are used to "draw
ducting or for installing clamps.
up" the sheets being riveted in order to eliminate any
opening between them before the rivet is bucked. Each
Rotary Rivet Cutters
draw set has a hole 1/32 of an inch larger than the
diameter of the rivet shank for which it was made.
In case you cannot obtain rivets of the required
Sometimes, especially in hand-working tools, the draw
length, rotary rivet cutters may be used to cut longer
set and the rivet header are incorporated into one tool.
rivets to the desired length. See figure 4-2. When you
The header consists of a hole sufficiently shallow for
use the rotary rivet cutter, insert the rivet part way into
the set to expand the driven rivet "bucktail" and form a
the correct diameter hole. Place the required number of
head on it when a hammer strikes the set. Figure 4-3
shims (shown as staggered, notched strips in the
shows a rectangular-shaped hand set that combines the
illustration) under the head and squeeze the handles.
draw and header sets and a flush set used with a
The compound action from the handles rotates the two
pneumatic hammer.
discs in opposite directions. The rotation of the discs
shears the rivet smoothly to give the correct length (as
Sets used with pneumatic hammers (rivet guns) are
determined by the number of shims inserted under the
provided in many sizes and shapes to fit the type and
head). When you are using the larger cutter holes, place
location of the rivet. These sets are the same as the hand
one of the tool handles in a vise, insert the rivet in the
rivet sets except that the shank is shaped to fit into the
hole, and shear it by pulling the free handle. If this tool
rivet gun. The sets are made of high-grade carbon tool
is not available, diagonal-cutting pliers can be used as
steel and are heat-treated to provide the necessary
an emergency cutter, although the sheared edges will
strength and wear resistance. The tip or head of the rivet
not be as smooth and even as when they are cut with the
set should be kept smooth and highly polished to
rotary rivet cutter.
prevent marring of rivet heads.
Rivet Set
A rivet set is a tool equipped with a die for driving a
particular type of rivet. Rivet sets are used in both hand
Figure 4-3.--Rivet sets.
Figure 4-2.--Rotary rivet cutter.
4-2
