An experiment on a surface-finishing operation of an overhead cam block
auxiliary drive shaft was reported by Sirvanci and Durmaz (1993). The following is an adaptation of the original experiment. The part had a target value
of 75 𝜇m. The three experimental factors were type of insert (A), speed in
rpm (B), and feed rate in millimeters per minute (C). A 23 design was used;
the (−,+) levels for the factors are (#5023, #5074) for A, (800, 1000) for B,
and (50, 80) for C. The surface roughness of each part was measured by a
Surtronic-3 device. The design and data for the drive shaft experiment are
displayed in Table 4.17. The current setting for the surface-finishing process
is insert type #5023, 780 rpm, and 60 mm/min.
(a) Analyze the experiment for both location and dispersion effects by using
appropriate methods presented in this chapter.
(b) Make recommendations on the optimal factor settings for location and
dispersion effects. Is it appropriate to use the two-step procedure?