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Millennium Patterns, Leeds, Alabama,
produces wooden and plastic metal casting patterns on a CNC machine
that costs only one-fourth as much as those normally used for the
task. When the pattern industry switched to CNC several years ago,
most companies purchased small machining centers that cost in the
area of $80,000 including programming software. Millennium Patterns,
when it started operations one year ago, decided instead to purchase
a lighter-duty CNC machine designed specially for wood and plastic
machining. Co-owners Joel Busler and Jim Collins said that with less
overhead than its competitors, the company was able to reach full
capacity within a few months of opening its doors by providing its
customers high quality patterns at a very attractive price.
Patterns are used in the foundry
industry to produce sand molds that are used to cast the actual
part. Patterns for parts that are produced in quantities of
thousands require metal patterns that must be produced on machining
centers. On the other hand, wood or plastic patterns are used for
parts that are produced in smaller quantities because of their lower
cost. Just a few years ago, these patterns were typically produced
on lathes and bandsaws by highly skilled operators who often spent
days or even weeks finishing each piece. The problems with this
approach were 1) it was very labor-intensive, 2) accuracy depended
on the skill of the worker and 3) a mistake made it necessary to
scrap the piece and start over.
The advent of CNC machining changed this
business in a major way. Pattern producers could now define their
pattern to a very high level of accuracy on the computer and have it
automatically cut to the precise geometry that they specified. The
only problem was the cost of the machine tool. A working area of
about 14 by 24 by 5 inches is normally considered to be the minimum
required for pattern work. A machining center of this size would be
ideally suited for a pattern company that produces metal patterns
but has far more rigidity than is required for wood, plastics and
lighter metals.
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Using CNC routing methods has been a
key to Millennium's success in the pattern business.
The two owners of Millennium Patterns
had each been in the pattern business for about 12 years when they
decided to start the firm. Their primary concern in starting the
business was the need to finance an expensive machining center that
they felt they had to have to be competitive in the business. That’s
why they were pleasantly surprised, shortly before going off on
their own, to discover a machine designed specially for lighter duty
machining at a much lower price.
The Techno Series III gantry router from
Techno, Inc., New Hyde Park, New York is similar in function to a
CNC machining center. At about $20,000 including software, the
machine is considerably less expensive than a machining center and
designed for lighter duty work. Yet, it provides the same surface
finish and accuracy as a machining center. Its working area of 29.5
inches by 21 inches with a Z-axis height of 11 inches, is larger
than nearly all machining centers in the under-$100,000 price range.
The machine can handle virtually any type of material although it is
limited to relatively small depths of cut in ferrous and other
tough-to-machine materials. In fact, one key feature is the Techno
servo system's ability to cut 3D continuous contours at up to 200
inches per minute, far faster than most machining centers.
Millennium purchased the machine and its
owners were able to teach themselves to operate it in a day or so.
This was largely because the Mastercam CNC programming software,
from CNC Software Inc., Tolland, Connecticut, supplied with the
machine was easy to learn. |
Although originally designed for metal
working, Mastercam is also well-suited for industrial design models
because of its ability to generate the most complex contours with
little programming effort. Mastercam includes IGES, DXF and CADL
converters so that geometry can be uploaded from many CAD systems
The machine proved to be ideally suited
to pattern making. When they first opened their doors, they didn’t
have any work and used the machine to machine 12 foot long signs
that helped draw attention to their business. As business started
trickling in, they demonstrated that they could produce patterns to
the same high level of quality that is achieved by more expensive
machine tools. The Techno machine's .0002 inch resolution and
repeatability and 0.003 inch/ft. absolute accuracy are the result of
several features inherent to the table, such as the use of ball
screws and servo motors. For example, anti-backlash ball nuts permit
play-free motion that makes it possible to produce accurate circles
and inlays.
Millennium showed that they were able to
produce patterns at the same high level of quality as that attained
by more expensive machines.
Once they proved that they could match
the quality of larger shops using more expensive machines, business
really started to take off. The firm was able to offer lower prices
than many of its competitors because it didn’t have the burden of
having to pay off an expensive machine. Another factor that helped
keep costs down was the many years of programming and machining
experience possessed by both of its owners. It was also often able
to offer faster delivery times than the larger pattern shops. Within
a few months, Millennium Patterns was operating at 100% capacity.
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