To accurately layout sections, such as halves or quarter
sections onto a pipe, use a length of paper cut to the exact
length of the pipe circumference, or mark it at that point.

     In the above example, the pipe will be divided into four
equal parts. To do this, take the paper and fold it precisely in
half, and then fold again. You will have a paper that looks
like the cash register tape strip at the top of the drawing,
with three fold creases in it.

     When wrapped around the pipe, it divides the pipe into
four equal measurements of 12.56" each. Transfer the
crease marks onto the pipe. It helps to place a line on the
paper at each crease so that it can be easily seen. You must
also have a centerline on the pipe to begin with for a start-
ing point.