QC tools, cost-of-quality, and lean/JIT fundamentals.

Which QC tool typically ranks defects from most frequent to least frequent?

• Control chart

• 5 Whys

• Pareto chart

• Fishbone diagram

A main objective of linking QC data to cost data is to:

• Confuse operators with more numbers

• Justify ignoring quality in favor of speed

• Identify where defects cost the most money

• Eliminate the need for TQM or CI

In Lean, the term “8 Wastes” includes:

• Muda, Mura, Muri, Overload, Overproduction, Overthinking, Overemphasis, Overcontrol

• Overproduction, Waiting, Transport, Motion, Inventory, Overprocessing, Defects, Unused talent

• Duplicates, Reverse engineering, Logistical errors, Office mistakes, Redundancies, Sunk costs, Tolerances, Unstable processes

• Overload, Overwork, Overpay, Overstock, Overheat, Overtime, Overstuff, Overrun

Which statement about JIT is true?

• JIT requires large buffers to handle unpredictable defects

• JIT is a push system that builds inventory in advance

• JIT focuses on producing only when there’s demand (pull)

• JIT always produces higher defect rates

In a push system, one typical downside is:

• You can’t produce any items without a signal

• You need zero inventory on hand

• Large WIP accumulates if a downstream station is slower

• Defects are automatically prevented

If a station has a 5% defect rate in a push system:

• That station instantly fixes all defects before sending them on

• You might accumulate many defective items at downstream stations

• Defects have no effect on cost-of-poor-quality

• Operators will always detect them immediately

How does SPC help in a manufacturing process?

• Eliminates all variation permanently

• Randomly sorts production tasks

• Distinguishes normal variation from special cause

• Guarantees zero defects by design

A main purpose of 5 Whys is to:

• Quantify the cost of each defect

• Provide a final solution without analysis

• Rapidly do a mental check of all 8 wastes

• Drill down to the root cause by repeatedly asking why

If data shows “Solder bridging” causes 60% of rework cost:

• There’s no need to tackle it since it’s only one defect

• This is normal variation—ignore it

• It’s likely a top priority for improvement

• Add more WIP to cover the defect backlog

Flexible manufacturing systems typically:

• Require complex setup changes for each product variant

• Use automation/CNC to enable quick changeovers

• Cannot handle small batches or custom orders

• Avoid any form of standardization