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Steelworker Volume 02 - Building manual for how to work with steel | Next
Figure 2-87.—Correct and incorrect riveting. |
When you are joining sheet metal that is greater than
two thicknesses, remember that the shank of the rivet
should extend 1 1/2 times the diameter of the rivet.
This will give you adequate metal to form the head.
Rivet spacing is given on the blueprint or drawing
you are working from. If the spacing is not given,
space the rivets according to the service conditions the
seam must withstand. For example, if the seam must
be watertight, you will need more rivets per inch than
is required for a seam that does not have to be
watertight. No matter how far apart the rivets are, there
must be a distance of 2 1/2 times the rivet diameter
between the rivets and the edge of the sheet. This
distance is measured from the center of the rivet holes
to the edge of the sheet.
Figure 2-85.—Hand punch.
After you have determined the size and spacing of
the rivets, mark the location of the centers of the rivet
holes. Then make the holes by punching or by drilling.
If the holes are located near the edge of the sheet, a
hand punch, similar to the one shown in figure 2-85,
can be used to punch the holes. If the holes are farther
away from the edge, you can use a deep-threaded
punch (either hand operated or power driven) or you
can drill the holes. The hole must be slightly larger
than the diameter of the rivet to provide a slight
clearance.
Riveting involves three operations-drawing,
upsetting, and heading (fig. 2-86). A rivet set and a
riveting hammer are used to perform these operations.
The method for riveting sheet metal follows:
1. Select a rivet set that has a hole slightly larger
than the diameter of the rivet.
2. Insert the rivets in the holes and rest the sheets
to be joined on a stake or on a solid bench top with the
rivet heads against the stake or bench top.
3. Draw the sheets together by placing the
deep hole of the rivet set over the rivet and striking
the head of the set with a riveting hammer. Use a
light hammer for small rivets, a heavier hammer
for larger rivets.
4. When the sheets have been properly drawn
together, remove the rivet set. Strike the end of the rivet
LIGHTLY with the riveting hammer to upset the end of
the rivet. Do not strike too hard a blow, as this would
distort the metal around the rivet hole.
5. Place the heading die (dished part) of the
rivet set over the upset end of the rivet and form
the head. One or two hammer blows on the head of
the rivet set will be enough to form the head on the
rivet.
Figure 2-86.—Drawing, upsetting, and heading a rivet.
2-29
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