Planning a practical garment-factory experiment

Learning objectives

• Explain the purpose of planning a practical garment-factory experiment in a garment-factory improvement project.
• Apply the described method to a representative shop-floor situation.
• Recognize the common mistakes and how to avoid them.

Concept

A practical DOE plan joins statistical design with safety, production, material, measurement, and operational controls.

Include purpose, hypotheses, factors/ranges, response, sample size, random order, blocks, replication, material lots, gauge readiness, hold/release rules, safety, stop criteria, data sheet, and approvals.

Deviations must be recorded and never silently replaced by convenient runs.

Variables, units, and assumptions

Temperature (°C), pressure (kPa), dwell (s); bond strength (N/cm).

Gauge repeatable, panels representative of lot, operators trained.

Free-spreadsheet workflow

Free spreadsheet: list all runs, assign random order with RAND(), block by lot, execute, record Y and deviations.

Interpretation and limitations

Compare effect estimates to replicate SD to judge significance and practical importance.

Findings valid only within tested ranges and lot conditions.

Garment-factory example

Test fusing temperature, pressure, and dwell time using panels blocked by fabric lot, with bond strength and appearance responses.

Method

1. Confirm MSA.
2. Complete risk review.
3. Generate run sheet.
4. Label specimens.
5. Brief the team.
6. Execute randomized runs.
7. Log deviations.
8. Preserve samples.

Common mistakes

• Letting operators choose run order.
• Altering settings outside approved limits without documentation.