# JCB Cab Quality Engineering Training

By James Levin

Topic: Engineering

[Open the interactive Jig](https://ask.jig.com/j/hEJ8z65srGSg)

## Guide

### 1. A glass room built to protect

This is the operator's cab of a JCB backhoe loader: the room where a driver works all day\. Its steel frame is built to protect the driver if the machine rolls over or something falls on it\. Every cab must be right before it leaves the factory\. Drag to look around\.

The frame is tested to the roll\-over standard ISO 3471 \(ROPS\) and the falling\-object standard ISO 3449 \(FOPS\)\.

### 2. Many teams, one cab

A cab is built from parts made by many companies: glass, seats, wiring and more\. Supplier quality engineers check those companies\. Manufacturing engineers plan how the cab is built, production teams build it, and quality and warranty teams make sure it stays right\.

Glowing parts come from outside suppliers; the yellow frame and roof are welded and painted in\-house in this example\.

### 3. ISIR: the first\-sample report card

Before a supplier sends parts for real, it sends a few first samples\. Every numbered size on the drawing is measured and written in an Initial Sample Inspection Report, or ISIR\. Press the button to measure a sample door glass\.

One edge is outside its tolerance, the allowed range, so this sample is rejected until the supplier fixes its process\.

### 4. Built right on the line

Production teams follow a plan for every cab\. Key features, such as the even gap around the door, are checked on every cab with simple gauges\. Steady results mean the process is under control\.

A control plan lists what is checked, how often and with which tool\.

### 5. The water test finds a leak

Every cab passes through a spray booth that soaks it like a heavy storm\. Inspectors look inside for any drip\. Press the button to start the rain and watch the top of the door\.

When a fault is found, suspect cabs are held back first so none reach a customer\. This is called containment\.

### 6. 8D: contain, then find why

The team solves the leak with 8D, eight steps for solving problems\. They form a team, describe the problem, contain suspect cabs, and ask why until they reach the root cause: a door seal with a lip too short to close the gap\.

Asking why five times helps a team look past the first easy answer\.

### 7. Fix it, prove it, prevent it

A taller seal with a longer lip fixes the cause, and repeat water tests prove it works\. The team then updates drawings, checks and training so the leak cannot come back, and thanks everyone who helped\.

Lessons go into the FMEA, a list of what could go wrong and how it is prevented\.

### 8. Listening to the field

Warranty teams track problems customers report after machines start work\. Each bar is one month of leak claims\. Compare the months with and without the fix to see how the real world confirms it\.

These are example numbers for training, not real JCB data\.

### 9. Quality is a loop

Inspect, measure, solve and learn: each finding makes the next cab better\. This never\-ending loop is called continuous improvement\. Take one more look around the finished cab\.

Many small improvements, made every day, add up to fewer defects and safer, more comfortable cabs\.