SPC Factory Simulator: CNC Bore

Interactive SPC training simulator. Monitor a CNC lathe, detect out-of-control conditions, investigate factory logs, and find the root cause.

15 min readIntermediate

SPC Factory Simulator

Step into the shoes of a quality engineer. Can you catch the problem before bad parts ship?

You Are the Quality Engineer

It's 6:00 AM. You just clocked in for first shift at a CNC machining cell. You're responsible for monitoring bore diameter on a lathe that produces transmission housings. The night shift operator says everything ran fine, but you know better than to take anyone's word for it -- you check the data. Your control chart is your eyes on the process.

Today's Assignment

Your CNC lathe has been running stable, but something is about to change. A hidden process event will occur during your shift. Your job is to detect it on the control chart, stop production before bad parts ship, dig through the factory logs to find the root cause, and annotate the chart like a real quality engineer would.

Machine

CNC Lathe, Cell 14

Part

Transmission Housing Bore

Characteristic

Bore Inner Diameter

Unit

LSL 24.950 Target 25.000 USL 25.050

How This Simulator Works

Watch the Chart

A live X-mR control chart plots one measurement every few seconds. The process starts stable. Watch for trends, shifts, or rule violations.

Stop Production

When you see something wrong, hit the red STOP button. The longer you wait, the more bad parts ship and the lower your score.

Investigate the Logs

After stopping, 5 factory logs appear: Raw Material, Operator, Maintenance, Environment, and Tooling. The root cause is hidden in one of them. You must find it.

Annotate and Score

Select the root cause, mark the chart where the problem started, and write an annotation. You'll be scored on detection speed, investigation accuracy, and annotation quality.

Don't wait too long! If too many out-of-spec parts ship before you stop production, the scenario fails with a customer complaint. Just like real life.

The chart will begin plotting immediately. Stay alert.

Are you a trainer? View the answer key and facilitator guide

Try It Yourself

Want to check YOUR process capability? Paste your data into our free tool.

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