Figure 4. Pliers in a TK-105/G.
so a wrench can be used to give greater leverage to the screwdriver. Some have blades with specialized
tips. For instance, some tips have a square cross section, some a flattened "8" or butterfly-shaped cross
section, some a hexagonal cross section, some a square cross section, and some a nearly oval-shaped
cross section. Some screwdrivers lack the usual wooden or plastic handle, and are offset so as to allow
working in a narrow space and still allow enough twist to be applied to the screwhead or bolthead.
However, as figure 5 shows, the typical tool kit for the electronic equipment repairman contains an
assortment of flat tip and Phillips' cross tip screwdrivers. In figure 5, items A thru E are flat tip
screwdrivers; items F and G, cross tip, Phillips' No. 2 size and No. 1 size respectively.
c. Wrenches: With a wrench, you can apply much more leverage or torque to a bolt or a nut then
you can with the ordinary straight-shank screwdriver. A good mechanic knows his wrenches and how to
use them. He never uses any wrench as a hammer. He always selects the right wrench for a particular
task. Whenever he has to tighten a nut or a bolt, he uses a wrench of sufficient length for applying
enough torque or leverage to tighten it as much as necessary, but not too much. With a wrench that's too
long for the task, a 'heavy-handed" mechanic may overtorque something, with embarrassing results such
as a cracked casting, a bolt with its head snapped off, a bolt broken in two, a nut with stripped threads, or
a nut that has pulled a bolt in two. On the other hand, a wrench not long enough for the task may create
several bad situations. If the mechanic desires to loosen a tight nut or bolt, for instance, and his wrench is
too short, he may not be able to apply enough torque to even budge the nut or bolt. If he has to tighten or
fasten the nut or bolt, and his wrench is too short, the result may be that the nut or bolt
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