bender, called a hickey (fig. 5-40), and the one-shot
bender (fig. 5-41). The one-shot bender is normally
made for EMT, but some are made to be used for both
EMT and rigid. The one-shot bender was given this
name because a full 90-degree bend can be made with a
single motion. Conduit sizes up to 1-inch rigid or 1 1/4-
inch EMT can be bent without much trouble with
manual benders. Larger sizes are bent with mechanical
or hydraulic benders. Hydraulic benders will be
discussed at the second-class level.
Rigid Nonmetallic Conduit
Although a complete line of factory elbows (90, 45,
or 30 degree) are available, bending PVC conduit (1/2
through 2 inch) is accomplished easily with the use of a
PVC hot box. A PVC hot box is nothing more than a
heater, enclosed by metal having a mirror finish on the
inside with openings on each end. To bend PVC
conduit, place the conduit inside the hot box, turn the
switch on, rotate the conduit until it becomes flexible,
remove the conduit, and bend it to the desired shape.
The hot box is a heater. If you leave the
conduit in long enough, it will BURN. You
should use gloves when bending PVC.
Electrical Metallic Tubing (EMT)
Conduit bending is a precise art form. You will use
degrees, angles, measurements and prefigured
deductions for radiuses and shrinkage. Combine all
these calculations correctly and you will get a finished
AMOUNT OF TAKE-UP
FOR 90° BENDS
SIZE AND TYPE OF CONDUIT TAKE-UP
3/4" EMT OR 1/2" RIGID*
1" EMT OR 3/4 RIGID*
1 1/4" EMT OR 1" RIGID*
*IMC AND RIGID WILL BE THE SAME
Figure 5-41.One-shot hender.
product that is not only functional but pleasing to the
eye, and something to be proud of.
90 DEGREE BENDS.One of the most common
bends you will make in the field is the right-angle bend,
more commonly called a 90-degree bend, or just a 90.
Anyone can make a 90 in a stick of conduit and then cut
it off to make it fit the situation, but this practice wastes
time and material. The secret is to bend the conduit in
the right place so that you do not have to cut it. To
accomplish this, there are some things you have to
know. First, you need to know the distance from the end
of the conduit to the back of the 90. This distance is
called the stub-up. Second, the radius of the bend takes
up a part of the stub-up. This part is called the take-up.
The amount of take-up depends on the type and size of
conduit you are bending. (See table 5-2.)
Table 5-2.Conduit Take-up