Conduit Bending

The Cosecant of the angle times the off-set desired is equal to the distance between the bends. First bend must be exact and last bend must make all level

There is a chart in trigonometry called the:
        Natural Trigonometric Functions 
        
        This is where the multiplier for the distance between the bends 
of an off-set comes from. It is the cosecant of the angle.

The cosecant of 15 degrees is 3.89
The cosecant of 30 degrees is 2
The cosecant of 45 degrees is 1.4


        If you will try to stay with these three angles, they will be
easy to remember and all your conduit off-sets can be made to match.
If you have need of another degree of angle (which you probably will),
then you can find the cosecant for that angle in many charts and on many
conduit benders. Remember, the cosecant is the multiplier for the  
distance between the bends of an off-set.

        Notice that the multiplier for a 30 degree angle is 2; A 30 degree
angle works out very well in most of your off-sets. If you need more
distance between the marks, use a 15 degree angle.
If you need to make a closer off-set, use a 45 degree angle.

        I referred to the marks. The marks are the marks on the conduit 
between the bends of an off-set. If you want to make a 6 inch off-set,
then the distance between the marks for a 30 degree angle would be 12
inches. Put the first mark where you want the front of the bending shoe,
and the second mark would be 12 inches away. The actual bend will be
about 1/2 the take-up, so remember that in matching your bends to the 
same location.

        When you make your first bends on any bender, check the actual
angle that the bend is. Some benders are mechanical, and you count the
number of pumps. Some are hydraulic with degrees of angle marked on them.
Regardless of the type, find the actual angle at the marked bender or
the pumps. Use a protractor angle finder. The reason I say this is,
that if you want a 6 inch off-set, and you mark the conduit for a 30 
degree angle, and the actual angle is only 28 degrees, then the off-set
will not be 6 inches, check the angle, if you want a 6 inch
off-set with 12 inches between the marks, you must have a 30 degree
angle. 

                             Front of shoe
                                 |
                              ======
                  Mark           |
                   |            Mark
        =========

	When making an off-set there is a measurement for the length of
conduit called take-up. This take-up is the distance lost from making
the off-set. The amount of this off-set take-up, is dependant upon the
angle used and height of the off-set, add the amount to length of conduit
run to compensate for the loss.

		10 degrees= 1/16 th inch
		22 1/2 deg= 3/16 th inch
		30 degrees= 1/4 inch
		45 degrees= 3/8 inch
		60 degrees= 1/2 inch
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