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Fishbone Diagram Generator

Create interactive fishbone diagrams for systematic root cause analysis using the Ishikawa method for problem solving

Fishbone Diagram Generator

High Defect Rate in Electronic Assembly

Man (People)
Insufficient train...
Operator fatigue
Poor communication
Machine (Equ...
Temperature drift
Poor maintenance
Calibration issues
Material
Inconsistent quali...
Storage conditions
Supplier variabili...
Method (Proc...
Outdated procedure...
Process variation
Inadequate control...
Measurement
Gage repeatability
Inspection criteri...
Data collection er...
Mother Natur...
Humidity fluctuati...
Temperature variat...
Contamination

Man (People)

Machine (Equipment)

Material

Method (Process)

Measurement

Mother Nature (Environment)

🔍 Next Steps for Root Cause Analysis

Prioritize causes: Use data, voting, or impact assessment to identify the most likely causes

Investigate root causes: Use the “5 Whys” technique to dig deeper into each potential cause

Collect evidence: Gather data to support or refute each potential cause

Develop action plans: Create specific actions to address confirmed root causes

Monitor results: Track improvements after implementing corrective actions

Understanding Fishbone Diagrams

A fishbone diagram, also known as an Ishikawa diagram or cause-and-effect diagram, is a visual tool used to systematically identify and organize potential causes of a problem. Named after its fish-like appearance, it was developed by Kaoru Ishikawa in the 1960s.

The diagram helps teams brainstorm and categorize potential causes, making it easier to identify root causes and develop targeted solutions.

The 6M Categories for Manufacturing

Man (People)

  • • Training and skills
  • • Experience level
  • • Fatigue or stress
  • • Communication issues
  • • Supervision quality

Machine (Equipment)

  • • Equipment condition
  • • Maintenance status
  • • Calibration accuracy
  • • Age and wear
  • • Technology limitations

Material

  • • Quality of raw materials
  • • Supplier consistency
  • • Storage conditions
  • • Specifications compliance
  • • Contamination issues

Method (Process)

  • • Work procedures
  • • Process design
  • • Standard operating procedures
  • • Process controls
  • • Documentation quality

Measurement

  • • Measurement accuracy
  • • Gage repeatability
  • • Data collection methods
  • • Inspection procedures
  • • Statistical methods

Mother Nature (Environment)

  • • Temperature and humidity
  • • Lighting conditions
  • • Noise levels
  • • Cleanliness
  • • Weather conditions

How to Create an Effective Fishbone Diagram

Step-by-Step Process:

  1. 1Define the problem clearly and specifically
  2. 2Assemble a diverse brainstorming team
  3. 3Identify major cause categories (6Ms)
  4. 4Brainstorm potential causes for each category
  5. 5Ask “Why?” for each cause to find root causes
  6. 6Prioritize and investigate the most likely causes

Best Practices:

  • • Focus on causes, not symptoms
  • • Be specific and detailed in your causes
  • • Use data to support potential causes
  • • Include all team perspectives
  • • Keep the session focused and time-bound
  • • Follow up with action plans for root causes

Fishbone Diagram Applications

Manufacturing

  • • Product defect analysis
  • • Equipment failure investigation
  • • Process variation reduction
  • • Quality improvement projects

Service Industries

  • • Customer complaint analysis
  • • Service delivery problems
  • • Process improvement
  • • System failure analysis

Healthcare

  • • Patient safety incidents
  • • Medical error analysis
  • • Process standardization
  • • Quality of care issues

Real-World Example: High Defect Rate Analysis

Problem: 15% Defect Rate in Electronic Assembly

Key Causes Identified:
  • Machine: Soldering iron temperature drift
  • Material: Inconsistent solder paste quality
  • Method: Inadequate work instructions
  • Man: Insufficient operator training
  • Environment: Humidity fluctuations
  • Measurement: Inconsistent inspection criteria
Root Cause Analysis Results:
  • • Primary cause: Temperature control system failure
  • • Contributing factor: Operator training gap
  • • Environmental factor: HVAC system issues
  • • Process issue: Outdated work procedures

Result: Implemented temperature monitoring, updated training, and improved HVAC controls. Defect rate reduced to 2.1% within 30 days.

Frequently Asked Questions

How do I know when I’ve found the root cause?

A root cause typically has three characteristics: it can be controlled or influenced by the organization, it directly contributes to the problem when present, and addressing it prevents the problem from recurring. Use the “5 Whys” technique to dig deeper.

Can I modify the 6M categories for my industry?

Absolutely! While 6M works well for manufacturing, service industries often use 4P (Policies, Procedures, People, Plant/Technology) or 8P categories. The key is using categories that make sense for your specific context and problem type.

How many people should be involved in creating a fishbone diagram?

Ideal team size is 4-8 people with diverse perspectives and knowledge of the process. Include operators, supervisors, engineers, and quality personnel. Too many people can make the session unwieldy, while too few may miss important perspectives.