CASE 4: SHORT-TERM SCHEDULING

Stan's Furniture Refinishers has 7 items of furniture tosand first and then varnish using the sending and varnishingmachines, respectively. The items and their times on these twomachines are shown in the table:

                               Item                      Sanding time,hrs.              Varnishing time, hrs.

                               A                                            8                                             7

                               B                                            6                                            4  

                               C                                            5                                            8

                               D                                            8                                            12

                               E                                            10                                         14  

                               F                                            12                                          8             

                               G                                            4                                             6

               

Questions.

1. Using the Johnson’s rule, identify the optimalsequencing of these jobs. The jobs must go through the machines inthe same order starting with the sanding machine.

2. Identify the cumulative flow time for the initialsequencing and for the sequencing based on the Johnson’s rule.Provide the existing sequence chart and Johnson’s rulecharts.

3. Compare and explain your results.