HOW TO QUICKLY MULTIPLY SKILLED WORKERS
TRAINING WITHIN INDUSTRY
The lens-grinder problem - TWI Job Instruction
Many operations are highly dependent on operator skill, so companies’ ability to increase capacity quickly is often constrained by how quickly additional operators can be trained. Training within Industry’s Job Instruction program (TWI JI) was developed to shorten the time for skills-acquisition so people can quickly learn to do a job correctly, safely and conscientiously at the required pace.
This case study is a great illustration of how Training within Industry can dramatically shorten training times for highly skilled or hard to learn work. It describes how the United States TWI Service managed to multiply production capacity in just a few months for a highly-skilled operation that had previously required several years to master.
The problem - long skills learning-curves - and ‘key’ insights how to solve it
In 1940, shortly after it was created, the Training within Industry Service received its first assignment.
There were serious concerns about shortages in different types of skilled work, including lens grinders and polishers. In the summer of 1940 there was an urgent requirement for an additional 350 properly qualified lens grinders to support arms production. The problem was, however, that mastering the lens-grinding art at the time required five years or more.
When the Training within Industry team set out to study the work, it found that lens grinding involved twenty operations. Up to this time it had been assumed that a lens grinder had to master all twenty operations to be qualified to work, but the team found that only a few of them involved precision work. Many aspects of the supposedly difficult work turned out to be relatively simple and easy. The team proposed to train new lens grinders in the fourteen easier operations and concentrate the limited pool of existing lens grinders on the most advanced aspects of precision optics.
This required production specifications and intensive training. Each or these fourteen tasks was analysed and broken down by an experienced worker. The team discovered that for each operation a few critical points determined whether the whole operation was successful. It was possible to isolate and explain these critical points: they were the keys to good work and good lenses, and were soon referred to as ‘key points’, which soon became a central concept in TWI Job Instruction - the most well known of the Training within Industry programs.
How to pass on skills…
Once the method of lens grinding had been broken down and understood, the team gave careful consideration to how the lens-grinding operation, with its key points, could be passed on. The TWI Service team initially recommended a 7-Step Method, originally developed by C.R.Allen and enhanced by the addition of key points:
Show him how to do it
Explain key points
Let him watch you do it again
Let him do the simple parts of the job
Help him do the whole job
Let him do the whole job - but watch him
Put him on his own
During the war, the instruction method was further refined, ending up with the 4 Step Method of TWI Job Instruction we know today.
… and how it doesn’t work
In November 1940 these steps were published in a bulletin, Helping the Experienced Worker to Break in a Man on a New Job that highlighted the value of key points, taking small instruction steps one at a time, and proposed a good method of instruction.
By providing this information, the TWI Service team expected plants to be able to go ahead on their own, break down their own skilled jobs and multiply their key workers. However, they quickly learnt that just stating principles and steps was not enough. Plants needed a complete programme teaching them exactly how to instruct skills on the job and how to ensure the new job instruction method was used to deliver the required impact quickly.
This led to the development of the TWI supervisor skills development programmes of Training within Industry.
Most managers have experienced skills shortages in a specific role in their organisation or currently live with the risk of ‘single points of failure’ where skills and know-how are concentrated in one or only few key experts that have become ‘indispensable’. Skills shortages can be solved and know-how easily passed on with the help of TWI Job Instruction.
This case study was shared by C.R.Dooley, the Director of the Training within Industry Service in his 1946 report on Training within Industry (TWI) to the International Labour Organisation.
The Training within Industry programs continue to be relevant to manufacturing and service organisations. In fact, Training within Industry is one of the foundations of the Toyota Production System and Lean.