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C A S E S T U D I E S
CAM Software Helps Improve Sinker-EDM
Electrode Programming and Cycle Time
The production of electrodes
for die-sinking EDM
represents one of the most
difficult CNC programming
challenges. The electrodes
have complex geometries
and must be machined with
high precision. Also, they
are produced in small lots,
even one-offs, so programming
time has to be as short
as possible. The EDM Department,
an American firm
that provides EDM tooling
and contract manufacturing,
has been able to answer
all these challenges with the
help of Esprit Knowledge-
Base CNC programming
software supplied by DP
Technology.
“The Esprit Knowledge-
Base machining capabilities
enable us to embed our
machining expertise within
the software, which substantially
reduces programming
time,” explains Mark
Raleigh, the president of
EDM Department. “We are
using knowledge-based machining
to develop a storehouse
of optimized machining
operations that we use
over and over again to
ensure that each of our programmes
is as productive as
possible.”
Raleigh’s company previously
developed CNC
programmes for the electrodes
with 2D programming
software. A problem
with this approach was the
common requirement for many trigonometric
calculations to define the part
geometry.
In addition, the software could not
accommodate 3D contoured surfaces;
EDM Department programmers could
write their own G-code and attach it to
the programme, but that took a lot of
time and was practical only for simple
contours. More G-code had to be created
in-house to programme newer-generation
machine tools.
So, Mark Raleigh decided to invest
in a state-of-the-art solid-model-based
CNC programming system. He chose
Esprit KnowledgeBase because its features
that allowed the company’s own
machining and tool expertise to be
embedded would save time by automating
many otherwise tedious programming
functions.
Adds Raleigh, “The knowledge base
also can help reduce machining cycle
times by providing programmers with
standardized operations that
have been optimized by
highly skilled and experienced
programmers.”
This software, like diesinking
EDM itself, is especially
helpful in programming
electrodes for medical
device components, many of
which are characterized by
high aspect ratios. The EDM
Department uses the design
of experiments method to
determine the optimal machining
conditions for the
challenging cuts sinker electrodes
necessitate.
“Esprit gives us the ability
to make adjustments in
very fine increments, as well
as the ability to save machining
operations for use on
future electrodes,” explains
Raleigh.
The company uses Esprit
to programme its die-sinking
EDM machines as well.
Here, programming allows
restarting a stopped job just
where it left off. The new
programming software and
methods have helped the
EDM Department reduce
programming time significantly,
even for the most
complicated parts, while
also increasing machining
productivity.
“The ability to create a
realistic simulation of the
complete machining operation
has nearly eliminated
programming errors,” Raleigh
reports, observing that
this accelerates machine setup. Cycle
times are shorter because optimized
machining operations that are archived
can be applied to features quickly.
“Esprit also makes it easy to change
and evaluate machining operations,”
concludes Raleigh, “which makes it
practical to continually improve our
programming methods.”
DP Technology Europe
MONTPELLIER, FRANCE
www.edme.info/2009/09/075
48 EDM EUROPE • AUTUMN 2009