High Speed Machining Precision Tooling - Indobiz.biz

Re-defining
Precision
It’s important not to limit the defi nition
of precision to one in particular, but
instead expand the defi nition to three
unique precision types: micro precision,
ultra precision and nano precision.
If you were to Google “precision
machining,” the results would be
staggering with more than a half million
hits. If you were to narrow the search with
“precision milling,” the results would be
far less with roughly 41,000 hits. Still
that seems to be an awful lot of hits and
we don’t even know if the hits pertain to
actual machine shops or not. However,
if you were to dig further into the results
and visit many of the actual machining
Web sites from those results, you would
be amazed at the number of companies
that call themselves a precision shop
with no clear indication of what defi nes
them as a precision manufacturer. Some
of these companies go beyond the word
precision and defi ne themselves as
military precision, medical precision
or commonly Swiss precision. So the
question is: What defi nes precision
today?
Defining Precision
A clear defi nition is needed to uniquely
identify the best in class shops in a
highly competitive market. Because the
market spans over a very broad range
of industries, it’s rather important not to
limit the defi nition to one in particular,
but instead expand the defi nition to
three unique precision types.
These types can be identifi ed as micro
precision, ultra precision and nano
precision.
By these three types, precision can be
identifi ed in regards to the technology
that a shop might have and what you can
expect in quality and accuracy instead
of using a generic term as precision.
Further, each precision type also can
be used to defi ne the technology and
expectations within a machine tool
and can be further used to defi ne the
maximum part quality that can be
expected of the machine without over
complicating things.
Precision can now be narrowed to micro
precision as precision defi ned by ±5
microns or less on the workpiece; ultra
precision as precision defi ned by ±2.5
microns or less on the workpiece; and,
nano precision as precision defi ned by 1
micron or less on the workpiece.
Understanding Microns
As you can see we’re no longer talking
in terms of English units, but instead
talking in terms of Metric units. This
method is not only clearer but simpler
to work with than thousands, tenths
or millionths. Working with microns
also is a universally understood unit of
measurement and is clearly known and
widely accepted around the world.
It allows us to defi ne closer tolerances
much easier. For example, rather than
saying 40 millionths or .00004” it is
much easier to say 1 micron or 1 um.
Chart 1 will provide you with a clear
illustration of equivalent units.
In re-defi ning precision, it’s important
to understand the micron unit. There
are several reasons why. First, it gives
a better picture of the three types of
precision.
Secondly, it brings the manufacturing
world in line with the advance technology
that is available on the market today—
from the machine tool to inspection
equipment. Additionally, it articulates
the trends in product designs toward
closer tolerances and miniaturization.
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indometalworking news Vol. 2 / 2008