The needle is one of the smallest parts of the machine but
is probably the most important. It is the source of the perfect
stitch and also the most aggravation. The use of the
correct type and size of needle is most important in
proper operation of a sewing machine. Improper needles
will cause a machine to produce poor stitching and may
damage the material, or the machine might not sew at all.
Using the wrong needle can also damage the machine.
Figure 6-73 shows the parts of a needle. Without getting
into the advanced aspects of needle technology, there are
a few simple things for the rigger to know.
1. There are three types of points—round, diamond,
and twist. Round is used for cloth as it separates the
fibers of the cloth as it passes through. The diamond
is used for leather as it cuts the material.
2. Each type of needle has a number to identify its size.
A typical description would be “16 x 95, size 20”.
The 16 is the size or diameter of the shank. The 95 is
the length and also describes the type of point. Odd
numbers denote round points and even, diamond
points. The size 20 is the diameter of the shaft.
3. The rigger should always follow the instructions in
the operator’s manual for the proper needle, installation,