is drawn into the wood to prevent the bolt from turning as the nut is
tightened. A washer is used under the nut, but not under the head of
d. Toggle Bolts. Toggle bolts are used to fasten fixtures to
hollow walls. The two types of toggle bolts are the pivot type and
the springwing type. Both types have heads similar to those of
ordinary wood screws. Both come in various sizes.
(1) PivotType. The pivottype has a bentsteel channel with
the nut slightly offcenter so that one end of the channel is heavier
than the other (Figure 149). A hole is drilled into the hollow wall
or block. The heavy end of the nut drops down at a right angle to
the bolt when it is inserted into the hole. The nut will pull up
tight against the drywall or block as the bolt is tightened.
Pivot-type toggle bolt
(2) SpringWing Type. Springwing type toggle bolts are
made like the pivot type except that the wing is hinged
in the center. It is held open with a small spring and