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Machinists and Tool Programmers

(D.O.T.  007.167-018; 600.260, -022, .280-022, -026, -030, -034,
-042, .281-010, .380-010; 609.262-010; and 714.281-018)

Nature of the Work

Machinists produce precision metal parts, usually using machine
tools such as lathes, drill presses, and milling machines.  Although
machinists can and sometimes do produce large quantities of one
part, machinists often produce small batches or one-of-a-kind items.
They set up and operate a wide variety of machine tools and know the
working properties of metals such as steel, cast iron, aluminum, and
brass.  Using their skill with machine tools and their knowledge of
metals, machinists plan and carry out the operations needed to make
machined products that meet precise specifications.

   Increasingly, the machine tools used to produce metal parts are
numerically controlled (NC) that is, they contain an electronic
controller that directs the machine's operations.  Most NC machines
today are computer numerically controlled (CNC), which means that
the controllers are computers.  The controller reads a program a
coded list of the steps necessary to perform a specific machining
job and runs the machine tool's mechanisms through the steps.  The
quality of the products these machines produce depends largely on
the programs, which may be produced by machinists or by workers who
specialize in programming machine tools known as tool programmers.
Although tool programmers and machinists are often considered
separate occupations, because many of their duties are very similar
or identical, both are covered in this statement.

   Machinists first review blueprints or written specifications for a
job.  Next, they calculate where to cut or bore into the workpiece,
how fast to feed the metal into the machine, and how much metal to
remove.  They then select tools and materials for the job, plan the
sequence of cutting and finishing operations, and mark the metal
stock to show where these cuts should be made.

   After this layout work is completed, they perform the necessary
machining operations.  Machinists position the metal stock on the
machine tool drill presses, lathes, milling machines, or others set
the controls, and make the cuts.  Today, new machinery allows
various functions to be performed with one setup, which reduces the
need for additional, labor-intensive setups, saving time and money.
During the machining process, they must constantly monitor the feed
and speed of the machine.  Machinists must also ensure that the
workpiece is being properly lubricated and cooled because the
machining of metal products generates a significant amount of heat.

   Traditionally, machinists have had direct control of their machines.
However, the introduction of numerically controlled machines, and in
particular, computer numerically controlled machines, has greatly
changed the nature of the work for machinists.  NC machines not only
are more productive, they enable parts to be produced with a level
of precision beyond that possible with traditional machining
techniques.  Furthermore, because precise movements are recorded in
the program, they allow this high level of precision to be
consistently repeated.  This uniformity is key to fulfilling
customers' needs for quality products.

   Tool programmers begin as machinists do by analyzing blueprints,
computing the size and position of the cuts, determining the
sequence of machine operations, selecting tools, and calculating the
machine speed and feed rates.  They then write the program in the
language of the machine's controller and store it.  Skilled
machinists also do programming.  As computer software becomes more
user friendly, machinists are expected to perform this function
increasingly.

   Machinists may work alone or with tool programmers to check new
programs to ensure that machinery will function properly and the
output will meet specifications.  Because a problem with the program
could damage the costly machinery and cutting tools, computer
simulations may be used instead of a trial run to check the program.
If errors are found, the program must be changed and retested until
the problem is resolved.  Programs can then be used for other jobs
with similar specifications by making small adjustments to the
existing program.  This reduces the time and effort needed to start
production of a part.

   A growing number of firms have computer-aided design (CAD) systems
that are used to write programs.  When a part is designed using a
CAD system, data about its dimensions are calculated; the CAD system
can then use these data to develop the controller's program.

   As machinery has become more complex, close tolerances or high
precision of machined parts has also increased in importance.  In
some cases, for example, a part may have to meet specifications
equal to one-twentieth of a strand of hair.  As a result measuring
devices have also increased in sophistication.  Optical, acoustical,
and laser measuring devices commonly ensure that work meets
specifications.

   Although machinists and tool programmers perform many similar
duties, jobs can vary greatly.  Some machinists, often called
production machinists, may produce large quantities of one part,
especially parts needing unusually complex operations, great
precision, or when unusually sophisticated, expensive machinery is
used.  Usually, however, large numbers of parts requiring more
routine operations are produced by metalworking machine operators
(see the statement on metalworking and plastics-working machine
operators elsewhere in the Handbook).  Other machinists do
maintenance work repairing or making new parts for existing
machinery.  For example, to repair a broken part, maintenance
machinists may refer to blueprints and perform the same machining
operations that were needed to create the original part.

   Machinists frequently use lathes to make round or circular parts.

Working Conditions

Most machine shops are well lighted and ventilated.  Nevertheless,
working around high-speed machine tools presents certain dangers,
and workers must follow safety precautions.  Machinists must wear
protective equipment such as safety glasses to shield against bits
of flying metal and earplugs to protect against machinery noise.
They must also exercise caution when cleaning and disposing of
coolants and lubricants because many of these materials can be
hazardous.  The job requires stamina because machinists stand most
of the day and may lift moderately heavy workpieces.

   Some tool programmers work in offices that are near, but separate
from, the shop floor.  These work areas are usually clean, well
lighted, and free of machine noise.

   Most machinists and tool programmers work a 40-hour week.  Evening
and weekend shifts are becoming more common as companies invest in
more expensive machinery.  Overtime is common during peak production
periods.

Employment

Machinists and tool programmers held about 359,000 jobs in 1992.
Most machinists worked in small machining shops or in manufacturing
firms that produce durable goods such as metalworking and industrial
machinery, aircraft, or motor vehicles.  Maintenance machinists work
in most industries that use production machinery.  Although
machinists and tool programmers work in all parts of the country,
jobs are most plentiful in areas where manufacturing is
concentrated.

Training, Other Qualifications, and Advancement

A high school or vocational school education, including mathematics,
blueprint reading, metalworking, and drafting, is desirable for
becoming a machinist or tool programmer.  A basic knowledge of
computers and electronics is helpful because of the increased use of
computer-controlled machine tools.  Experience with machine tools
also is helpful.  In fact, many of the people who enter the
occupation have previously worked as machine tool operators or
setters.

   Machinist training varies from formal apprenticeship programs to
informal on-the-job training.  However, most employers consider a
formal apprenticeship program the best way to learn the machinist
trade.  Apprentice programs consist of shop training and related
classroom instruction.  In shop training, apprentices learn filing,
handtapping, and dowel fitting, as well as the operation of various
machine tools.  Classroom instruction includes math, physics,
blueprint reading, mechanical drawing, and shop practices.  In
addition, as machine shops have increased their use of
computer-controlled equipment, training in the operation and
programming of numerically controlled machine tools has become
essential.  Community colleges and technical institutes increasingly
offer classroom training in connection with company or association
training programs.

   Qualifications for tool programmers vary widely depending upon the
complexity of the job.  Basic requirements parallel those of
machinists.  Employers often prefer skilled machinists, tool and die
makers, or those with technical school training.  For some
specialized types of programming, such as with complex parts for the
aerospace or shipbuilding industries, employers may prefer
individuals with a degree in engineering.

   For those entering tool programming directly, a basic knowledge of
computers and electronics is helpful because of the increased use of
computer-controlled machine tools.  Experience with machine tools
also is helpful.  Classroom training includes an introduction to
numerical control and the basics of programming and then advances to
more complex topics such as computer-aided design.  Then, trainees
start writing simple programs under the direction of an experienced
programmer.  Although machinery manufacturers are trying to
standardize programming languages, currently there are numerous
languages in use.  Because of this, tool programmers must be able to
learn and adapt to new programming languages.

   Established workers may also take courses to update their skills and
to learn the latest technology and equipment.  Some employers offer
tuition reimbursement for job-related courses.  In addition, when
new machinery is introduced, workers receive training in its
operation usually from a representative of the equipment
manufacturer.

   Persons interested in becoming a machinist or tool programmer should
be mechanically inclined.  They also should be able to work
independently and do highly accurate work that requires
concentration as well as physical effort.

Job Outlook

Employment of machinists and tool programmers is expected to decline
slightly through the year 2005.  Nevertheless, many job openings
will arise each year from the need to replace experienced machinists
and programmers who transfer to other occupations or retire.  In
recent years, employers have reported difficulties in attracting
workers to machining and tool programming occupations.  Therefore,
good employment opportunities should exist for candidates with the
necessary mechanical and mathematical aptitudes.

   The number of openings for machinists is expected to be far greater
than the number of openings for tool programmers because there are
many more machinists than tool programmers.  In addition, machinists
are increasingly taking on the functions of tool programming as the
programming of machine tools becomes easier due to simplified
programming languages and procedures.

   As the economy expands, so will the demand for goods that use
machined metal parts.  But, demand for these workers will be
constrained by improvements in metalworking technology.  For
example, the use of computer-controlled machine tools reduces the
time required for machining operations and increases productivity.
Furthermore, when demand for machined goods falls, machinists and
tool programmers involved in production may be laid off or be forced
to work fewer hours.  Apprenticeship opportunities may also decline.

   Employment of machinists involved in plant maintenance is often more
stable because proper maintenance and repair of costly equipment
remain vital concerns even when production levels fall.

Earnings

Earnings of machinists compare favorably with those of other skilled
workers.  In 1992, median weekly earnings for machinists were about
$492.  Most earned between $376 and $623.  Ten percent of all
machinists had median weekly earnings of less than $275; the 10
percent with the highest earnings made more than $750 a week.  In
addition to their hourly wage, most workers receive health and life
insurance, a pension plan, paid vacations, and sick leave.

Related Occupations

Occupations most closely related to that of machinist and tool
programmer are, of course, the other machining occupations.  These
include tool and die maker, tool and die designer, tool planner, and
instrument maker.  Workers in other occupations that require
precision and skill in working with metal include blacksmiths,
gunsmiths, locksmiths, metal patternmakers, and welders.

   Tool programmers apply their knowledge of machining operations,
metals, blueprints, and machine programming to write programs that
run machine tools.  Computer programmers also write detailed
instructions for a machine in this case a computer.

Sources of Additional Information

   For general information about this occupation, contact:

   The Association for Manufacturing Technology, 7901 Westpark Dr.,
McLean, VA 22102.

   The National Tooling and Machining Association, 9300 Livingston Rd.,
Fort Washington, MD 20744.

   The Tooling and Manufacturing Association, 1177 South Dee Rd., Park
Ridge, IL 60068.

   Precision Metalforming Association, 27027 Chardon Rd., Richmond
Heights, OH 44143.


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