United Grinding - The Grind Magazine - August 2015 Issue
also in this issue . . .
TO FLY IN AEROSPACE
EXPLORE THE UNIVERSE
For Greater Production
and Profitability page 3
LESSONS LEARNED FROM SPACE, Hubble Space
Telescope Repair Mission, Page 30
ADVANCED SPINDLE TECHNOLOGY
Tackles ID Grinding, Page 46
REBUILD AND RETROFIT:
Key Life Cycle Options for
Grinding Machines, Page 22
ID GRINDERS END SHOP’S PART
TOLERANCE NIGHTMARES, Page 16
3 DIRECTOR’S CUT
4 GRINDING IN MOTION
5 CAREER TRACK
20 A GLIMPSE INTO
40 DIGITAL DIGEST
48 IN THE ZONE
55 LAST THOUGHT
D E P A R T M E N T S
F E A T U R E S
6 Welcome to The UNITED GRINDING Universe
Where today’s advanced grinding frontier boosts
12 Shop Grinds Precision Parts for Land, Sky and Space
MÄGERLE machines help shop profile grind critical
parts for NASA.
16 ID Grinders End Shop's Part Tolerance Nightmares
STUDER helps global valve manufacturer reduce
scrap and speed up operation.
22 Rebuild and Retrofit: Key Life Cycle Options
for Grinding Machines
Two ways to refresh production capacity in older
26 BLOHM Grinder Installed at the AMRC
BLOHM machine assists in advanced machining
research for aerospace sector.
30 10 Lessons, 1 Story
NASA astronaut relates Hubble Space Telescope
repair mission to manufacturing.
36 CNC Grinding Launches Shop's Aerospace
and Defense Work
STUDER machine helps shop regain full control
of its grinding operations.
42 Shop Combines Automated Grinding
and Swiss-Style Turning
STUDER helps shop establish niche in high-volume
precision parts production.
46 Advanced Spindle Technology Tackles ID Grinding
High-speed spindle capacity and wheel size key
to ID grinding success.
52 Importance for Proper Filtration and Temperature
Control in Grinding
Modern metalworking filtration systems take
a lot of heat these days.
Grind/Grinding Universe Issue 2015 1
technical school or degreed program at a community college or
It should be noted that 50 percent of STEM-related jobs do
not require a four-year degree, but a certificate or two-year
associate degree, according to a Brookings Institution report.
That is why young people need to consider all their educational
opportunities. By starting with an associate degree, the overall
cost of an education is much lower, and students can then earn
a four-year engineering degree while earning a living.
There are no quantifiable numbers on whether the push for
STEM education and emphasis on careers in manufacturing
are working. The research only goes back a few years,
and it will take more time to see if the number of young
people going into manufacturing and engineering programs
increases. We certainly have seen many school systems
launching or improving their STEM programs.
A great way for young people to see where a STEM education
can take them is Manufacturing Day — an outreach initiative
where manufacturers invite young people and the community
to come in and learn about manufacturing. This allows those
young people to interact with industry professionals and learn
about today’s manufacturing sector as well as applicable career
4 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 5
On April 29, 2015, Walter s.r.o. held
a groundbreaking ceremony for the
expansion of their production site
in Kuřim, Czech Republic, a project
involving an investment of $6.5 billion
(6 billion euros). To enable additional
growth, the assembly area will be
expanded by 21,500 square feet
(2,000 m²) and a new 7,000 square
feet (650 m²) shipping hall will be built.
In celebratory speeches, Drago
Sukalovský, mayor of Kuřim, Jürgen
Schock, Walter Maschinenbau GmbH
CEO, and Michael Horn, United
Grinding Group AG COO, praised
the commitment of the enterprise
in the Kuřim region, a traditional
center of mechanical engineering.
As a production company for Walter
Maschinenbau GmbH, the local entity
Walter s.r.o. is part of the United
Grinding Group AG.
In their speeches, Franz Dettling,
managing director at Walter s.r.o.
and the responsible architect, Daniel
Makovský, emphasized the production
related advantages of the new
building. In addition to the expanded
area, a structured floor space concept
for an optimized value-added chain is
key to the entire concept.
Walter s.r.o. had already invested
approximately $8.7 billion (8 billion
euros) in 2014 to expand the
machining department by a new pallet
automation system and to acquire
new machining centers. At the Kuřim
site, this expansion also included
modern offices and a larger cafeteria.
Kuřim has been building machines
for Walter Maschinenbau GmbH
in Tübingen, Germany since 1996.
Initially, the focus was on the
production of WALTER tool-grinding
machines; however, this was quickly
expanded by Kuřim’s own range of
CNC measuring machines. With the
integration into the United Grinding
Group AG of Körber AG holding
with annual sales of more than
$2.4 billion (2 billion euros,) further
machines from the United Grinding
Group AG’s grinding portfolio
complement the range.
Future Skilled Labor
Stems From a Good
Due to general economic growth and expansion, and
baby boomers retiring left and right, U.S. manufacturing
continues to desperately need more skilled workers. In 2012,
The Manufacturing Institute and Deloitte LLP released a
well-publicized study that estimated about 600,000 skilled
manufacturing jobs were going unfilled. Although that job
number is down to about 300,000 on a monthly basis, a new
2015 study suggests that by 2025, the number could be as
high as 2 million. Of the 3.4 million manufacturing jobs likely to
be needed over the next decade, only 1.4 million are expected
to be filled as a result of the skills gap.
The AMT — The Association For Manufacturing
Technology is working hard to build the workforce that will
combat this problem. In addition to working on policy in
Washington, D.C., AMT lobbies at the state level and in
local communities to encourage more young people to
seek careers in manufacturing. This includes extensive
collaborative efforts with national organizations, middle
and high schools, career and technical schools, community
colleges and engineering schools to bring as much
awareness as possible to careers in manufacturing.
One well-promoted step is to get students, parents and
teachers interested in science, technology, engineering and
math (STEM) education and, hopefully, in manufacturing. AMT
provides information on how students can receive the right
education for a career in manufacturing, as well as where to
get that education, whether they seek a certificate from a
Vice President of Smartforce Development,
AMT – The Association For Manufacturing Technology
WALTER MASCHINENBAU GMBH HOLDS
GROUNDBREAKING FOR EXPANSION
of its production site in Kuřim, Czech Republic
1 STUDER: “Small Footprint - Big Results” Match Grinding
with the perfect machine pair.
2 STUDER: Cylindrical Grinding to the highest accuracy
for many industries.
4 STUDER: Radius Grinding of Complex Workpieces
5 STUDER: Precision and Passion for ID Grinding
of Parts with a Large Diameter.
7 with the Key to Measurement Technology.
8 EWAG: Progressive Thinking in an Environment
that requires Out of the Box Solutions
9 “Free Parts” - Utilizing Automation and Software
to Maximize Lights Out Manufacturing
11 BLOHM: Continuous Dress Creep Feed Grinding.
“Mastering the Materials of Tomorrow”.
12 The Grinding Doc: How to Overcome Grinding Errors
and Achieve Maximum Results.
14 MARPOSS: In-Process Measurement
for Your Internal Grinding Applications.
15 NORTON: Precision Grinding faster than Machining
16 EBBCO: Non Standard Backwash Systems
17 MIKROSA: The Guide to Centerless Grinding
Main Training RoomCustomer Care Training Room Showroom No Presentation NEW!
The UNITED GRINDING Universe Event | OVERVIEW AND PRESENTATION SCHEDULE
W E L C O M E T O T H E U N I T E D G R I N D I N G
See the new STUDER S151
internal cylindrical grinding
The S151 has advanced features that
make it ideal for grinding spindle shafts,
spindle housings, rotor shafts, axes and
Network with executive
team members and brand
experts from Europe.
Representatives from each of the
UNITED GRINDING brands will be on
hand to help you find the best grinding
strategy for growing and/or optimizing
your unique operation.
Discuss specific grinding
Our experts will answer your questions
and show you how new developments in
surface and profile, cylindrical and tool
grinding can produce precision parts.
Check out an advanced
automation cell for
This demonstration will show you
how the right technology can help you
meet increased demand and enhance
The UNITED GRINDING Universe Event is the perfect place to discover new ways to
increase your competitive advantage. Throughout the event, you will see the latest
grinding technologies, techniques and turnkey solutions, and will experience first-hand
how ID/OD, match, creep feed, centerless, radius, universal and other modern grinding
techniques can improve productivity and boost part quality.
6 event highlights you do not want to miss.
A NASA astronaut for more than 30 years,
Musgrave flew on six spaceflights and was
the lead spacewalker on the Hubble Space
Telescope repair mission. His story and
magnetic personality will inspire you to
believe that anything is possible.
Experience the latest
in internal grinding
Our innovative internal grinding solutions
will be on display so you can see how to
best meet your toughest internal grinding
6 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 7
Beaupre is a Key Account
Manager for UNITED
engineer for cutting tool
companies, and the
owner of a diamond tool manufacturingbusiness.
He will uncover new ideas for capitalizing on
technology to become more competitive in
cutting tool manufacturing in his presentation
“Progressive Thinking in an Environment that
requires Out-of-the-Box Solutions.”
Badger has a Ph.D.
as well as extensive
experience on the shop
floor and working in
more than 30 countries.
He will present “How
to Overcome Grinding
Errors and Achieve
Maximum Results” where he will discuss
methods to eliminate burn in cylindrical
grinding, cope with shoulder grinding and
the common causes of problems with hitting
Hitchiner is OEM
Technology Manager at
Norton Abrasives and has
36 years of experience
in R&D and technical
field development of
abrasives. He will present “Precision
Grinding Faster than Machining,” highlighting
state-of-the-art ceramic grain and CBN
technologies and their applications. He will
analyze processes in terms of chip modeling
and explain how to exceed stock removal
capability and achieve cost benefits over
traditional machining operations.
8 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 9
William B. Cram
As Regional Sales
Manager for UNITED
America, Cram has sold
13 STUDER S41 grinding
machines since its
introduction in 2011 to
in aerospace, construction and agricultural
industries. In his presentation, “Economical
Cylindrical Grinding with Maximum Flexibility,”
he will review the features of the machine and
how its accuracy benefits customers.
Schuetz, Regional Sales
America, has 30 years
of grinding experience,
including HVOF coating
and reliable grinding
process and productivity.
His presentation, “Cylindrical Grinding to the
Highest Accuracy for Many Industries,” will
highlight how a STUDER machine is constructed,
optimized “grinding processes” and return on
Sorge has been a
Regional Sales Manager,
UNITED GRINDING North
America for nearly five
years. He will present
Creep Feed Grinding:
Mastering the Materials
of Tomorrow,” which will cover the typical
applications and benefits of continuous dress
creep feed grinding, including the usual feeds,
speeds and material removal rates. It will
conclude with a demonstration depicting the
attributes of continuous dress creep feed
Stolmar, Vice President,
Sales Tool Group,
North America, has been
with the company 15
years. He will present
“Driving Profitability with
Eroding PCD,” providing
an overview of the current status of machining
solutions, including grinding, erosion and
laser, for the manufacture of tools made from
superhard materials such as PCD, CVD and CBN.
Emerson is Regional
Sales Manager at
North America and has
30 years of grinding
experience in the areas
of sales, application
and service. His “Small
Footprint - Big Results – Match Grinding with the
Perfect Machine Pair” presentation will cover
the theory of grinding OD and ID ground parts
that will then be matched together. He will also
detail the machines, process, ancillary equipment
and the results.
Recently named to SME’s
30-under-30 list, Osborn
is Product Engineer
at UNITED GRINDING
North America. His
Grinding of Complex
Workpieces to Best
Possible Surface Finish,” will cover how to utilize
machine technology for forming complex shapes
in the ID of exotic materials with superabrasive
wheels, practices that can improve the surface
finish, and the wheels to properly execute an
internal grinding operation.
Wiss, Regional Sales
America, will present,
“The Art of CNC Profile
Dressing.” He will
demonstrate the ease of
CNC dressing of intricate
forms utilizing the GripsProfile 32 software
program by uploading a profile, generating
a dress simulation, dressing the grinding
wheel, confirming the accuracy of the dressed
form and modifying the grinding wheel to an
Powell, Product Manager,
Grinder Products, has 34
years at Marposs Corp.
He started as a service
in grinder applications
and has worked on a
development team for
autonomous manufacturing for an automotive
OEM. Powell’s presentation, “In-Process
Measurement for Your Internal Grinding
Applications,” will explain how the application
of in-process gauging can benefit a process and
the considerations required on an internal
Poppe is Process
Manager for Ebbco, Inc.
He is well known for
his practical, down-to-
earth explanations of
complex grinding topics
and will present on
“Non Standard Backwash Systems.” He will
discuss the benefits of clean, chilled grinding
fluids and what they can do for production, tool
life, part finish and carbide reclamation. He will
also highlight the benefits of backwash central
systems serving up to 20 machines.
for UNITED GRINDING
North America, Jackson
has been working
with STUDER grinding
machines for more
than 17 years. In his
presentation, “Utilizing Software to Obtain
Precision and Efficiency,”he will provide an
overview on how StuderGRIND software
can help program machines with proven
technologies that can reduce cycle time,
simulate machine movements and produce
accurate customer quotations.
Otto is Technical
Director, Centerless, at
SCHAUDT MIKROSA. He
will present “Guide to
which provides an
overview of past and
current machine designs.
He will then showcase new machine concepts
that will further enhance process possibilities.
America, has more than
20 years of experience
in the industry.
Efficiencies of Your Production with the Key
to Measurement Technology,” will showcase
the measuring machine portfolio of Walter
Maschinenbau GmbH and its capabilities.
Monnin is Regional
Automation Manager for
Acieta and has 30 years
of experience in factory
Rottet, Product Manager,
STUDER, has 33 years
of experience in the
grinding industry and
has participated in the
development of new
Rottet will present “Precision and Passion for ID
Grinding of Parts with a Large Diameter,” where
attendees will learn about new internal grinding
products introduced by STUDER, including some
application examples, and the new STUDER S151
and its capabilities.
pplication engineers will be
available during the more than
16 technology demonstrations
to answer questions and discuss
how new developments in surface
and profile, cylindrical and tool grinding
can produce precision parts at the best
possible value. Supplementary technical
lectures will follow these demonstrations
so attendees can further explore the
new grinding frontier.
The UNITED GRINDING Universe Event | PRESENTERS
10 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 11
STEPS TO SECOND FLOOR
UPSTAIRS WALKWAY/CATWALK TO TRAINING ROOMS
CUSTOMER CARE ROOM
FISCHER USAS.L. MUNSON HOFFMAN
Station 5Station 6
Station 8Station 9
MAIN TRAINING ROOM
The UNITED GRINDING Universe Event | EVENT MAP
Form Grind can grind any shape or profile generated along a surface. Specific
parts include turbine blades for aerospace engines, auxiliary power generators
and locomotive turbo chargers. For NASA, it profile grinds extremely precise
titanium hyperbolic quadrupoles used in space vehicles’ mass spectrometers.
The instruments analyze planetary atmospheres, a key task in the Cassini and
Established in 1978, Form Grind started out in a leased 4,000-square-foot
manufacturing space with two manual crush form grinders. Today, the company
is a 42,420-square-foot operation with ISO 9001:2008 certification, including the
AS9100 standard set forth by the aerospace industry to satisfy DOD, NASA and
FAA quality requirements.
Among its keys to success, Form Grind relies on the precision output of more
than 20 MÄGERLE surface and profile grinders from UNITED GRINDING and a
wide array of support equipment. The company also takes pride in its advanced
creep-feed grinding operations, which involves removing large amounts of stock
on any material in a single pass, with higher precision and better surface finishes
than conventional methods.
Form Grind produces turbine blades with tight tolerances and rigid specifications,
ranging in size from a few inches to over two feet long. For example, some
blades must meet weight tolerances reaching three decimals in grams in addition
to strict dimensional requirements. Because turbine engine manufacturers
F E A T U R E
12 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 13
orm Grind Corporation, located
in Rancho Santa Margarita,
California, employs precision
grinders, innovative processes
and experienced staff to process
critical parts for customers that
include energy-products makers,
major aerospace OEMs and NASA.
By using the latest CNC grinding
technology integrated with
engineering, tooling and quality
assurance, the company can
efficiently take on varying production
volumes while maintaining strict
customer requirements. In fact,
NASA’s Goddard Space Flight
Center recognized Form Grind for
its advanced engineering role in the
Cassini mission to Saturn and Maven
mission to Mars.
Form Grind can grind
any shape or profile generated
along a surface. Specific
parts include turbine blades
for aerospace engines,
auxiliary power generators and
locomotive turbo chargers.
14 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 15
"The beauty with creep feed
grinding or profile grinding is
that you can grind hardened
materials directly to size.”
then we’ll do another feature in a separate operation.
There is no real clear-cut best way to do things. When you
start a job you have to be pragmatic and look at what the
goal is, what the volume is and what it potentially could
be, and how elaborate your tooling should be to maximize
efficiency. It is all about easing cycle time out of the
process and achieving the most output.”
Shorter cycle times, however, must be achieved while
maintaining process security. Intricate casting processes
and new workpiece materials have pushed up the cost of
rough blade castings, with some valued at $1,000 or more.
As a result, much effort goes into establishing and verifying
a reliable process. “It is important to have an open structure
grinding wheel and speeds, feeds and coolant locations set
so that you are removing the material as fast as possible,
but also without burning or cracking parts,” Treichler said.
“We are very proud that we have less than one tenth of one
percent of scrap; OEMs tell us that that when they ship us a
set of 100 blade castings, we will send 100 blades back.”
Blade dimensions are verified through dual inspection
methods. Treichler said Form Grind always submits the
parts it grinds to two methods of inspection: “We check
first articles in the inspection room where we have a
CMM and a 30" optical comparator, then we empower the
operators to perform in-process inspection.” At each of
the more than 25 different grinders on the shop floor, there
is a surface plate where the operator can use hard tooling
and different types of go/no go and plug gages that verify
certain part features.
For final inspection, the CMM holds parts in a free state
to check and verify the six point nest dimensional features
on the blade. Such overall verification is not possible
in-process when a part moves from machine to machine
for different operations. “Turbine blades tend to have 100
percent in-process inspection, and in final inspection we do
a statistical process sampling,” Treichler said.
The Future of Grinding
Treichler is a firm believer in the key role of grinding in
the production of precision parts, especially of gas turbine
components. “A company tries to mill a feature then sends
the part out to heat treat and gets distortion. Then they try
to fix those distortions,” he said. “Milling can be consistent
and accurate, but for features such as fir trees with 0.002"
tolerances, the speed and capability of the diamond dresser
to dress all those points on a conventional wheel and grind
them all at once offers a clear advantage. The beauty with
creep feed grinding or profile grinding is that you can grind
hardened materials directly to size.”
When two sets of multi-piece fixturing are built for a
job, one is always on the machine and the grinder can
run continuously. Treichler pointed out that continuous,
accurate output is largely dependent on grinding machine
capabilities, and noted that the MÄGERLE machines,
some with 20" diameter wheels and 100-hp, water-cooled
AC spindle drives, run 20 hours a day, six days a week.
“To compete in a global environment you must have a
really strong piece of equipment that can continuously
grind parts,” he said. He added that the grinders’ rigidity
and strength also come into play when grinding the tough
nickel-base alloys that comprise most gas turbine blades.
The complexity and permanence of Form Grind’s
custom-fabricated tooling depends on job requirements.
Typically, a blade-grinding program of 100,000 blades a year
will employ elaborate, high-capacity tooling. Initial tooling
costs will be significant, but will be more than recovered
over the high-volume run. A blade program that has 500 to
1,000 pieces per year, on the other hand, may use fixtures
that hold six to 10 parts as opposed to 20 at a time, and
tooling costs will better match the program’s return.
Depending on factors such as blade size, workpiece
material, and tolerance requirements, Form Grind
establishes different grinding processes for different blades.
“For some larger blades we might want to creep feed grind
and reduce the reciprocation at the end of the process,”
Treichler said. “For other blades we may do some creep
feed passes and then some reciprocating and final dressing
at the very end. There is some tribal knowledge, or black
magic if you will, in the art and science of grinding.”
Form Grind begins process planning with a team that
includes marketing, tool designers, toolmakers and
production managers. “We try to see what makes the most
sense in terms of the best way to break down a process,”
Treichler said. “We will at times break up the operations to
where we use certain machines for the fir tree operation
continually raise the operating temperatures of their
products to reduce emissions and increase efficiency, the
blades often feature complex contours and internal coring
engineered to manage heat. The acute contours and coring
increase the challenges of grinding and fixturing the blades.
Form Grind fills a mid-range production niche. Vice
president and general manager Gary Treichler said,
“Although some blade programs are as large as 100,000
pieces yearly, at the end of the day we are a job shop.
Most of our runs are 500 to 1,000 blades at a time.”
CNC technology enables the shop to efficiently handle
varying volumes. While the shop’s first manual machines
required constant skilled attention, today’s CNC equipment
permits setting up multiple machines that can be tended by
one operator after production runs begin.
“We don’t do strictly untended operation, but certainly
there are jobs where cycle times may be 10 or 15 minutes
and an operator can load and watch multiple machines,”
Treichler said. “The CNC equipment basically allows us to work
smarter. We’ve had around 50 employees for the last 10 years,
and with additional MÄGERLE grinders we have doubled our
output over that decade with the same workforce.”
Quick job turnover is crucial for Form Grind. The company
may set up a job in a day, run it for two to five days, then
take it off the machine to make room for the next job.
Some jobs repeat on a monthly, quarterly, yearly or even
Form Grind’s responsiveness and flexibility is due in part to
the in-house design and fabrication of its workholding tooling.
“We are able to maximize efficiency by loading many parts
into holding fixtures,” Treichler said. “We want to maximize
efficiency where we get as many parts as close together as
possible to get the best bang for the buck.”
For smaller blades in 1" to 3" sizes, the shop uses
guillotine-type six point nest fixtures that hold 20 blades
for an operation. The fixturing is engineered to position
the parts so the wheel is not grinding air and operating at
shallow depths of cut, maximizing wheel usage.
16 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 17
ost people have work-related
dreams. However, for Ruben
Ramirez Jr., the grinding
supervisor at HydraForce, Inc.,
holding tight tolerances on complex
parts was a waking nightmare.
According to Ramirez, manufacturing
consistency and predictability is
crucial in meeting the company’s
goals of product quality and reliability
in its precision valve and manifold
manufacturing operations. A typical
challenge was grinding the ODs and
IDs of hardened-steel valve spool and
guide components. Used in valves
for agricultural and earth moving
equipment, the small, complex parts
are at most 12.7 mm in length and
usually less than that size in diameter.
The parts’ sizes and shapes made them
difficult to load and time consuming
to accurately grind their ODs on a
centerless grinder. Afterwards, the
parts would transfer to an ID grinder
where they were clamped on the
OD for internal grinding operations.
Achieving the required concentricity
took too much time, and the scrap rate
“We were scrapping on the first
operation and then adding to that scrap
from the second operation,” explained
Ramirez. “Needless to say that trying
to hold the specs the way we were
processing the parts was extremely
Today, HydraForce does its primary
cylindrical and ID grinding on STUDER
machines from UNITED GRINDING.
Among the STUDER machines at
the company’s Lincolnshire, Illinois,
facility are three S30 cylindrical CNC
grinders, an S21 cylindrical CNC and
two favoritCNC universal grinders.
However, most recently, HydraForce
added two STUDER ID CNC grinders:
a CT450 and a CT550. In both of the
machines, workpieces move on the
cross slide, while the internal grinding
spindles are fixed to the machine base,
thus maximizing stability and rigidity.
The arrangement also enhances
accessibility for workpiece set-ups and
changes and facilitates automation.
The spindle setup allows for up to
three internal grinding spindles to be
mounted in a linear configuration and
customized for specific applications.
The CT450 accommodates workpieces
up to 230-mm long and grinding
lengths of 150 mm, while the CT550
handles parts up to 650-mm long and
grinding lengths up to 150 mm. A
305-mm OD grinding wheel can be
mounted on either machine.
The modular, flexible arrangement
of spindles enables the machines
to be optimized for output volumes
ranging from individual parts to
large-scale production. The grinders
also support integrated and
autonomous loading systems.
F E A T U R E
Ramirez said the CT450 is fitted with OD and ID wheels,
enabling OD and face grinding as well as ID operations.
The CT550 has two ID spindles and can run three separate
internal grinding procedures.
“The concentricity or runout from one ID bore to another
on consecutive operations is essentially zero. It’s very
accurate,” he said, “Which helps us produce load holding
valves that have zero leakage.”
Ramirez’s grinding challenges were greatly reduced because
HydraForce can perform both OD and ID grinding on the
same CT450 machine. Previously, when grinding the valve
spools and guides, the OD and ID operations consumed
about five minutes each per part, not counting the time
lost transferring the parts between machines. And again,
the need to fixture the parts twice also contributed to
increased scrap rates.
“Now, on the CT450, we complete parts in a minute
and hold 0.0025-mm tolerances on both the IDs
and the ODs. And we’ve reduced scrap by about 75
percent,” said Ramirez.
HydraForce, founded in 1985 in Lincolnshire, supplies
hydraulic components to the mobile equipment industry.
The company provides a comprehensive selection of high-
quality cartridge valves, manifolds and high-performance
electronic controls for tractors, excavators, harvesters,
wheel loaders and material handling equipment. HydraForce
has manufacturing facilities in North America, Europe and
Asia and a network of 120 stocking distributors that support
The company employs a group technology approach to
product planning, design and manufacturing that utilizes a
few basic components to create many different models. The
cost-effective engineering strategy enhances manufacturing
consistency and product availability.
Early in its history, HydraForce sought subcontractors
for grinding but no suppliers were able to hold the tight
tolerances required by the precision valve components.
As a result, about 15 years ago the company began to
bring grinding operations in house, including both OD
and ID grinding processes.
HydraForce runs parts in batches of 500 to 10,000 pieces.
Although Ramirez typically prefers to finish an order for
one valve before beginning work on the next one, an
immediate customer request sometimes requires a run to
“Even though we switch back and forth many times and
we may make four setups a week on the same STUDER
machine, we are still able to hold dimensions,” he said.
For HydraForce’s CT450, experts from UNITED GRINDING
and robotic integrator Acieta, LLC worked together and
provided turnkey automation, and according to Ramirez,
the system helps keep the machine constantly running.
He added that the automation loads a part in about six
seconds, a loading speed of which an operator is incapable.
HydraForce plans to also fit its CT550 grinder with a similar
turnkey automation system.
“We were really impressed with the automation on the
CT450, and it made us realize that it is the way to go for
the CT550 as well,” commented Ramirez. “It will be a
great help if the operator doesn't have to be there the
majority of the day. This will free up that operator to run
another non-automated machine.”
Ramirez emphasized the importance of support from
UNITED GRINDING – from the ordering process through
the runoffs that prove the machine’s capability to make
HydraForce parts, to delivery and setup.
“They give us support throughout the life of the machines.
We have machines in here that are probably 12 years old,
and they still help us out,” said Ramirez.
He went on to say that quality drives HydraForce’s
manufacturing efforts. “It is on our mission statement
to provide our customers with the highest quality part,”
he said, and emphasized that the accurate, consistent
results from STUDER grinders help the company carry
out that mission.
“The concentricity or runout from one ID bore to
another on consecutive operations is essentially zero.”
“it’s very accurate ... which helps us produce load
holding valves that have zero leakage.”
18 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 19
Provides Advice at
Work and at Play
A G L I M P S E I N T O
Since I was a little kid, I have been interested in stars and space. I was hooked
the first time I saw Saturn and its rings, then when the Comet Shoemaker Levy 9
collided with Jupiter in 1994.
My most powerful telescope works at 480 X magnification, but even my lower
power one allows me to see the entire moon. I’m a fan of partial moons because of
the nice light and dark contrast. I’m also in the process of grinding my own telescope
lens by hand for even higher levels of magnification.
Another part of my hobby is astrophotography, which involves taking a series of
images over the course of a night. With a little Photoshop, I end up with cool very
professional looking photos. A camera is more sensitive than the human eye, and
that fact allows me to see the best colors.
I’m also a member of the Cincinnati Astronomical Society. We do a lot of outreach
stargazing events in public parks for people interested in astronomy. They look
through the various types and sizes of telescopes we have set up, and we answer
I guess you could say I not only advise people about the best grinding equipment,
but also about the best astronomy equipment. They are both application-driven. It
all depends on if the user wants to look at planets, be able to see far away or just
take pictures. Everything fits together as a complete package or process, just like a
What I enjoy most about UNITED GRINDING is working with the best people in the
industry. The amount of know-how within the company is incredible. If someone
doesn’t know the answer, they know the right person to ask. Everyone helps until
the problem is solved. I also enjoy the challenge of creating unique solutions for my
customers’ toughest jobs.
oth in my professional life and my personal life, people come to me for
advice. At work, I guide customers on how to best maximize a machine or
process, and as an amateur astronomer, I help people gaze at the stars.
At UNITED GRINDING, I find myself in the newly created position of sales
engineer for spare parts in the cylindrical division. I help customers with retrofits and
rebuilds, and this position allows me the flexibility to be their single point of contact.
When a customer calls about their STUDER machine, I examine the problem
from every angle, onsite or remotely. If the customer needs a better solution for
processing a part on that machine, I might suggest various gaging, clamping,
automatic loading, cycle-time reduction or programming solutions. Or they may
want to put a new product line through that machine or need after-sales support
to determine the best way to use the machine.
And being the single point of contact, I know the entire retrofit kit is going to
show up and be right the first time. If needed, I can even go to the site and
install the new parts, then train the operators on the retrofit machine.
I’ve been with UNITED GRINDING for seven years working as an applications
engineer in the cylindrical division and as a service engineer where I repaired
machines. Previously, I worked for an OEM machine builder running STUDER
machines. Other jobs I’ve had include a machine operator at an aerospace shop
and a FANUC integrator building automation cells. I’ve also worked as a hot rod
My father also works for UNITED GRINDING in the applications division. Coming
from a family of engineers and machine builders, I have always loved taking things
apart and figuring how to put them back together. I’m like the character in the old
TV show Star Trek — Lt. Commander “Scotty” Scott, chief engineer, which is also
appropriate considering my hobby is astronomy.
20 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 21
22 Grind/Grinding Universe Issue 2015
he productive life cycle of any machine tool is limited. Be it a lathe, mill
or grinder, a machine’s accuracy and reliability eventually will deteriorate.
How long that takes depends on the machine’s basic structure; how
often and hard it is used; and how it is maintained.
Shops that carefully track machine utilization find that downtime of 20 percent or
more of available machine time — due to unanticipated stoppages, adjustment
and maintenance — generally represents an unacceptable burden on scheduling,
maintenance operations and profitability.
Two key options available to recover grinding production capacity include
rebuilding the machine and retrofitting it with selected upgraded technology.
Shops can also repurpose existing grinders for work different than their original
intent, or replace them with brand new grinders.
Rebuild and Retrofit:
Rebuilding or overhauling a grinding machine involves
disassembling it entirely and examining every mechanical,
electrical, pneumatic and hydraulic system. Components
are replaced or repaired where necessary and re-qualified
to OEM standards. Every bolt, nut, rivet, hose and pipe
gets the same treatment. Newer technologies such as
monitoring devices may be added. Other updates can
include items such as LED lighting and controls. Except for
its basic structure, which is abrasive blasted and repainted,
the reassembled machine is essentially brand new.
A full rebuild costs about 75 percent as much as a new
machine. The typical rebuild cycle might be 15 years;
longer if the machine is lightly used and well maintained.
But that span is much shorter if the machine runs three
shifts a day, every day, with minimal maintenance. Large,
specialized grinding machines such as those used in critical
aerospace applications are prime candidates for renewal
via a comprehensive overhaul.
Depending on a machine’s overall condition and how it
has been used, a possible approach is a partial rebuild that
retrofits a machine with newer technology. If a machine’s
electrical systems and control are in top shape but the
machine has been worked very hard and/or received
minimal maintenance, only the mechanical systems
may need to be overhauled. This involves a replacement
of mechanical elements that are worn out or damaged
On the other hand, a machine’s
mechanical systems may be in
excellent condition, with inspections
confirming that axes and accuracy
match OEM standards. In that case,
an electrical overhaul including
replacement of the electrical cabinet,
all wiring and the servomotors may
be appropriate. The mechanics of the
machine and the original enclosure
If a machine’s CNC unit is outdated, a
new control will increase operational
speed, productivity and convenience.
An important consideration is the life
cycle of the control itself. Control
makers such as FANUC and Siemens
typically introduce new control
technology about every ten years.
So when needing a new control, it
may be advantageous to look for a
replacement control that is in the early
phase of its cycle to benefit from the
longer planned lifespan and control
F E A T U R E
Grind/Grinding Universe Issue 2015 23
Corporate budgeting policies may be a final determining
factor in the choice to rebuild or replace a grinding machine.
Restrictions on capital spending can make an overhaul,
which usually is considered a maintenance expense, the
only way to reclaim the production capacity of a worn
machine. On the other hand, some companies’ capital
spending strategies and allocations promote purchase of
new machines. Depreciation, incentives and other tax-related
issues can vary in relation to the age of a machine.
Advanced grinding machines from UNITED GRINDING
are engineered and manufactured to provide many years
of trouble-free, accurate and profitable service. Ongoing
maintenance, per manufacturer’s recommendations, will
further extend service life. And when a machine moves
toward the end of its initial life cycle, users have a range of
options regarding the best path to continued productivity.
24 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 25
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percentage of machines being repurposed will continue
to grow as the industry continues to move away from
long-term contracts for large volumes of identical parts
to more flexible and dynamic manufacturing scenarios
of rapidly changing part types and volumes.
Repurposing a grinding machine typically involves adding
features that will enable it to carry out more complex
and productive grinding or to work with ancillary systems
such as automation. A machine originally built in an open
configuration may require the design, fabrication and
addition of an enclosure to permit use of high-pressure
coolant and advanced technology grinding wheels. Another
machine might be repurposed to employ robotic automation
by fitting automatic doors with opening/closing drives and
laser-based safety systems.
A machine without the capability for rotary dressing can be
fitted with a rotary dresser and related drives and controls.
True reverse engineering is rarely needed, but adding
new systems can require re-engineering of hydraulic or
pneumatic systems and design and fabrication of new
sheet metal components.
An obvious alternative to a worn and unreliable grinder is
replacing it with a new machine. In many cases, however, the
choice between rebuilding and replacing is not so obvious.
Cost considerations play a key role in the decision to rebuild
or buy new. The 25 percent savings of a rebuild compared
with the price of a new machine is much less significant
when applied to the price of a new, basic 3-axis production
grinder than it is relative to the purchase of a multi-million
dollar machine engineered for specialized work. A perfect
example of such systems are those that grind aerospace
blades and vanes.
Lead times are another important factor. The lead time
for a new machine’s basic welded or cast iron structure
alone can be four to six months, depending on the size of
the machine. Adding those months to the time required
to construct the rest of the machine results in an eight
to fourteen month or longer total lead time — dependent
again on the machine’s size, type and brand.
The lead time for a rebuild may be only half that of a
new machine because the rebuild utilizes the machine’s
existing structure. But even that shorter delay can disrupt
production excessively. For example, a busy shop with five
3-axis grinders that all perform similar operations will lose
significant capacity during the months while a machine is
off the floor for a rebuild. Buying a new grinder enables
the shop to use the old machine to grind parts without
interruption until the replacement is ready to install.
A key element of control technology is the human-machine
interface, or HMI. A control with a state-of-the-art HMI will
incorporate an interactive, question-and-answer procedure
that enables an operator who is far from an expert in
programming to create productive grinding programs by
simply answering questions and entering relevant part,
wheel and machine data.
Some machines may work well overall but possess outdated
subsystems. Many elements of machine technology have
changed significantly over the last 15 to 20 years. The
feedback systems that locate machine axes are good
Machines with older motion encoders that do not feature
glass scales must execute a multi-minute homing process
to establish the positions of the machine axes each time
the machine is turned on. The absolute encoders in glass
scale systems, on the other hand, store the position of
axes when the machine is shut off or if power fails. This
eliminates the need for a homing routine when the machine
powers back on. The new encoders also offer resolution
100 times higher than previous measurement methods.
Servomotors have improved over recent decades as well,
and are perhaps 50 times more accurate than earlier
machine motion technology.
If a machine has not been updated in 15 to 20 years, adding
new and upgraded technologies can extend the next rebuild
cycle. For example, retrofitting a ball screw lubricating
system that was unavailable on the machine twenty years
ago will enable the ball screws to last significantly longer.
If the machine’s ongoing workload remains unchanged,
the time between rebuilds lengthens significantly.
In general, approximately 60 percent of overhauled
machines return to their facilities to handle basically
the same operations and workload they did prior. The
remaining machines undergo additional changes intended
to repurpose them for upgraded or different tasks. The
PROFIMAT MC 607 5-axis CNC grinding
machine manufactured by Blohm Jung
GmbH in Germany has been supplied
in close cooperation with UK agent, J.R.A.
Bennett Ltd, at The University of Sheffield
AMRC with Boeing. It follows a rigorous tender
process that involved evaluating hundreds of
parameters and included grinding trials at the
machine builder’s factory in Hamburg.
The moving-column grinding machine is located within
the Design, Prototyping and Testing Center, a major
expansion of the original AMRC building within the
Advanced Manufacturing Park, which is supported by
the High Value Manufacturing Catapult and the European
Regional Development Fund. The center concentrates on
the development of high-value manufacturing technologies
mainly for the aerospace, Formula One and high-end
Medical applications will also be developed, as earlier
this year a new facility was set up within the center,
called Medical AMRC, to concentrate specifically on
this industry. One application will be to investigate
finish grinding of prosthetics that have been 3D-printed
layer-by-layer from cobalt-chrome powder. Knee joints will
be a particular target due to their multiple profiled planes.
F E A T U R E
26 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 27
Capable of producing highly complex components,
the BLOHM PROFIMAT MC is ideal for supporting the
center’s aim of looking at how the design process can
reduce manufacturing costs long term, particularly
by combining different technologies. A highly capable
machine is desirable for such an endeavor. The PROFIMAT
has features in abundance to assist in research and
development programs and in evaluating wheel consumption
against metal removal for achieving different levels of
accuracy and surface finish.
The latest Siemens Solution line 840D control, which
includes a BLOHM user interface, can be used to program
the machine’s five CNC axes to interpolate simultaneously.
BLOHM Grinder Installed at the AMRC
The flow rate and pressure of the coolant are programmed
for each application to give the best results. Consistency
is achieved by automatically maintaining the same angle
between nozzle and wheel as the latter wears. It is
achieved by mounting the nozzle on a positioning unit
which is programmable in X and Y so that its distance
from the wheel and the orientation remain the same. The
cleaning jets are mounted just above the coolant nozzle,
which is angled directly at the point of grinding. The
carriage carrying both sets of nozzles is also adjustable
automatically or manually in the Z-axis.
Initial grindability trials have already been carried out on
Inconel and aerospace grade steels, with more exotic
materials destined for evaluation shortly along with the
cobalt-chrome alloy for medical applications.
Complicated surfaces may be generated in this way,
without using profiled wheels. Alternatively, one or both
of the rotary axes on the table can be clamped while the
others move simultaneously, a strategy that allows the
number of separate machining operations for producing
a component to be reduced, often to one. The result
is a reduction in manufacturing cost and an increase in
accuracy through less tolerance build-up.
All wheel dressing options are available on the machine,
including continuous, pulse and table dressing, as well as
contour generation of grinding wheel profiles. If one of
the in-process methods is chosen, one of two diamond
dressing rolls can be selected under program control from
an overhead, swiveling unit.
Flexibility of use extends to the ability to deploy mills,
drills and other cutters in addition to grinding wheels,
all housed in a 24-position tool magazine to the left of
the machine, ready for automatic change into and out of
the spindle. Grinding wheels up to a 16-inch diameter
by a 4-inch width can be employed. The machine will
accommodate all types of wheels, including aluminium
oxide, CBN (cubic boron nitride), vitrified CBN and
diamond electroplated steel.
The compact, 9.3-ton grinder is the next-generation
PROFITMAT MC, which offers higher rapid positioning,
especially in the Y and Z axes, than its predecessor. Direct
drives and larger ball screws have made it possible for
the machine to offer feed rates of 98 feet/min in X and 39
feet/min in Y and Z. The Y and Z axes have also benefited
from larger linear roller guideways. The design upgrade also
yields an acceleration of 7 feet/s2 in all axes, double of
what it was before. Linear scales are fitted for absolute,
high-precision feedback of axis positions to the control.
A 52 kW motor, HSK-A 80 grinding spindle and reinforced
wheelhead, coupled with increased machine rigidity,
lead to higher productivity and component accuracy,
commensurate with the type of advanced research being
carried out at the AMRC. A more accessible, swiveling
control panel that is adjustable for height, stainless steel
guarding and an automatic door as standard are extra new
features, along with safety integration in the control and
double wiring to provide redundancy for critical operating
To increase productivity, the machine has a wheel cleaning
system, called RazorTec®
, that projects filtered coolant
at the wheel at 30-40 bar pressure. This forces metallic
debris out of the porous structure of the wheel, keeping it
sharp and maintaining its profile. Furthermore, infeed rates
increase, stock removal is maximized and there is a lower
risk of burning the workpiece.
Grind/Grinding Universe Issue 2015 29
To increase productivity, the
machine has a wheel cleaning
system, called RazorTec®
that projects filtered coolant
at the wheel.
Flexibility of use extends to the
ability to deploy mills, drills and
other cutters in addition to grinding
wheels, all housed in a 24-position
tool magazine to the left of the
machine, ready for automatic
change into and out of the spindle.
PROFIMAT MC 607 at the AMRC,
showing the machine’s stainless
steel guarding and swing-out
When the coolant becomes a Liquid Tool.
Blaser Swisslube AG
3415 Hasle-Rüegsau, Switzerland Phone +41 34 460 01 01 email@example.com
«The right product – correctly applied,
and I guarantee a higher feed rate.»
Rico Pollak Head of Grinding Technology
28 Grind/Grinding Universe Issue 2015
fter the Hubble Space
Telescope was launched in
1990, NASA discovered a
significant flaw. The curvature
of the primary mirror was incorrect,
which affected the images sent back to
Earth. Twelve other major systems in
the telescope also needed repair. In
1993, I was part of a team of astronauts
sent up on Space Shuttle Endeavour to
do those repairs.
Part of the repair process required
us to go on a spacewalk to reach the
telescope. For such an undertaking,
it is critical to develop the solutions
then organize a plan to make sure they
are executed as precisely as possible.
And while this strategy ensures the
success of a NASA mission, it can also
provide valuable lessons for successful
manufacturing operations as well.
1. Teamwork is vital. In space, the
success of the mission and the safety
of the team is contingent on the team‘s
ability to work together. Each member
brings unique experience and important
expertise that can inspire others.
Collaboration and communication
is key to resolving challenges.
A big part of any manufacturing
operation is teamwork. Individuals
must work together to solve complex
problems and achieve goals that
are impossible for one person
to accomplish on their own. It is
F E A T U R E
imagination and listening and learning
from others. Once in space, there is
little that can be done from Earth to
fix a problem. But NASA’s engineers
always come up with creative
Manufacturing requires creative solutions
as well. Engineers like a challenge and
come up with innovations that are smart
and efficient. It must be a solution that
solves a real-world problem; however, a
solution that customers don’t really want
or need is not the answer.
4. Experience leads to innovation.
Part of finding solutions is using
experience, even from youth. While
performing the telescope repairs, I relied
on my past education and experience.
When I was 13, if the tractor broke down
while I was working in the field, either
NASA Astronaut and Lead Spacewalker,
Hubble Space Telescope
30 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 31
important to have an environment
that supports teamwork so each
member can share knowledge and
resources and be flexible to meet
2. Identify your goals. Part of a
successful NASA team is each member
knowing his or her job. Each person has
to have an identity and a clear role so
they know what is expected of them.
This also means they take responsibility
for their own actions.
In manufacturing, every team member
must know his or her mission and goals
as well. It benefits them to see how their
mission fits into the overall company.
3. Focus on solutions. Creating
solutions (finding a new and better
way) to achieve goals in space requires
I fixed it or walked home. So I fixed it.
Those were life-changing experiences.
In addition to education and training,
you have to rely on past experiences
in manufacturing. The tinkering and
problem solving you may have done in
your youth provides life-long lessons.
5. Communication ensures
continuity. Once NASA had the repair
solution, I had to choreograph the
dance. How am I going move the tools
around, change a part, move my body
into the correct position? It is taking
those steps and forming a pattern,
a rhythm, to accomplish the job. I
ultimately choreographed every detail.
And focusing on the steps, instead
of the end result, is what tends to
It is the same in the manufacturing
process. Once the course of action is
determined to create a product or solve
a problem, the plan must be laid out so
everyone knows his or her steps. Every
step that is taken in manufacturing is
integral to the process as a whole.
6. Work in iterations. Part of doing
the dance is having the right touch,
the right amount of finesse. To move
something in space, you drop it and
leave it. If you want it to go faster, you
give it a gentle push.
Finesse is important in manufacturing
as well. Not every problem needs to be
tackled head on, full speed. You have to
know when to try subtle changes and be
able to adapt to altering situations.
7. Pay attention to the details.
The success of any mission is in the
details. It is important to move to the
physical world and receive training
and perform testing. You practice and
practice. The knowledge has to be
in the body. You have to understand
what you are doing, how you are
going to do it and how good you are
getting at it.
10L E S S O N S, 1S T O R Y
9. Be curious. Why do we work so
hard to explore space? The instinctive
curiosity we come into the world with
requires a quest, a journey, to find
answers. The real reason for space
exploration is to reach out and touch
our universe, and be touched by our
It is the same with manufacturing. To
discover a better solution, you have to
have an interest in the result. Curiosity
leads you to explore alternatives.
10. Success is a marathon, not a race.
Human curiosity means looking
beyond our solar system into new
galaxies to discover something
unique. With manufacturing, you should
look to the stars for inspiration. You can
make a real difference in the world.
I worked on the Hubble Space Telescope
mission for 17 years, and I gave every
ounce of my being, as did my fellow
team members. We planned, worked
hard and accomplished tasks we had set
out to do. And that is the key to success
in anything in life. Dedication.
32 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 33
Training for the repair mission meant
working underwater in a NASA testing
pool to create the space experience.
Working in the tank showed me there
was only a 1" clearance between my
backpack and the structure. So I had
to figure out how to fit in the allotted
space on the telescope to apply the
right amount of torque for the repair.
Success in manufacturing also requires
proper training. A company that improves
its employees’ skills helps create a strong
team. Part of that is focusing on details.
Good production people pay attention to
the details and hate deviations.
8. Have the right tools to succeed.
To make the telescope repairs possible,
I had to have the right tool at the right
place and the right time. I eventually
designed about 300 tools for Hubble.
At NASA, we put real tools on real
instruments to get the feedback. I drove
the mechanism and I could feel it. So
when I was in space, it was not just a
blind turned bolt. I felt the bolt.
In manufacturing, no one can do his or
her job without the right tools, and it is
up to management to make sure team
members have what they need.
Human curiosity means
looking beyond our solar
system into new galaxies to
discover something unique.
you should look to the stars
for inspiration. You can
make a real difference
in the world.
S.L. Munson & Company
Representative for U.S.A., Canada and Mexico:
1404 Old Dairy - Columbia, SC 29201, U.S.A.
phone: (803) 252-321 or (800) 285-3211 - fax (803) 929-0507
web: www.slmunson.com e-mail firstname.lastname@example.org
34 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 35
O P T I M I Z E
op Shops from Gardner Business Media is an annual benchmarking program
for machine shops of all types and sizes. It allows owners and managers to
compare their operational practices with leading U.S. shops and single out
ways to emulate those top performers.
The comprehensive program collects survey data from several machining
companies to pinpoint optimal shopfloor practices as well as operational and
business metrics that define success in parts manufacturing. While the Top
Shops survey asks new questions every year, a core set of key questions
remains an annual staple. This allows Gardner to compare current and past
data for identifying industry trends.
Gardner presented the 2015 survey to
North American shops earlier this year,
which included independent shops that
primarily perform short-run and other
non-repeating work; contract shops
that are independent and primarily
have contracts for repeating part
numbers; and captive shops within a
While the survey itself encompasses
a broad range of topic areas, from
equipment types to workholding
strategies, this article hones in on industry
segments, investments, machining
strategies, profit margins, sales and
marketing tools and employees.
The 2015 survey data shows that
Top Shops tend to serve a wide variety
of industries, which suggests these
companies are highly agile and better
equipped to develop processes in
line with the latest market trends.
The greatest increases in industries
served by Top Shops were aerospace,
automotive and defense. Other leading
markets included machinery/equipment,
medical and oil and gas, although the
latter two were down slightly in the
On the nuts and bolts side of the
business, Top Shops tend to invest
more in capital equipment and use more
advanced machining strategies. Over
the past few years, the percentage of
Top Shops performing 5-axis positioning
and full simultaneous 5-axis contouring
has increased dramatically. Whereas,
those percentages remained virtually
unchanged or even decreased among
other shops. Furthermore, a higher
percentage of Top Shops perform more
high-speed machining as well as lights-
out operations than others.
From the survey, a variety of business
metrics demonstrate how Top Shops
have more effective overall operations.
The biggest indicator of business health
is profit margins, and Top Shops tend
to have higher profit margins than other
shops, even though the profit margins
for all shops have remained level. And,
while sales growth at Top Shops was
higher, the sales growth rate has slowed
for all shops across the board.
A greater number of Top Shops have
increased their use of sales and
marketing tools. These include websites
and YouTube videos — along with print
advertising, company tours and trade
shows — to taut their capabilities. For
other shops, the increase is minimal or
Top Shops also place high value on
employees, which is important in a
time when skilled labor is hard to find.
Top Shops will provide other benefits,
besides high salaries, to reward and
retain good employees. Additionally,
Top Shops tend to offer annual review
and pay-raise programs. And, when
compared with other shops, Top Shops
put more emphasis on formal training.
In fact, training programs at Top Shops
have grown immensely over the past
In summary, the 2015 survey results
indicate that Top Shops tend to
make greater investments in capital
equipment, advanced machine tool
technology and employees to ensure
the highest levels of production
capability and efficiency for optimized
shop floor operations. These investments,
along with strategic sales and marketing
efforts, thus lead to greater overall
By Steve Kline, Jr.,
Director of Market Intelligence,
Gardner Business Media
Top Shops tend to make greater investments in capital equipment,
advanced machine tool technology and employees to ensure the highest levels
of production capability and efficiency for optimized shop floor operations.
With new markets and customers
came the demand for increasingly
more complex and even higher
precision parts. “Anybody can make
the easy stuff,” Labrie said. “Our
customers’ engineers continue to push
the design and manufacturability limits,
and we embrace the challenge. We
have a great group of people here who
are really smart.”
Advanced manufacturing systems also
help J&E meet such challenges and
fulfill customer requirements. “We try
to stay on top of the curve as far as
technology goes,” said Labrie. “We
have the latest and greatest on the
floor, whether it is for programming
or machining or tooling. We are quite
willing to spend capital on equipment,
and make the right moves to keep our
It was with customer needs in
mind that the shop recently added
advanced CNC grinding capability to
maximize flexibility, precision and job
turnaround speed. Previously, grinding
capability at the shop was limited to
OD, ID and flat grinding and some
lapping on machines that were “old
relics,” according to Labrie. They
were incapable of any real production
work, so J&E subcontracted out its
production grinding. However, issues
with cost and scheduling constantly
“We manufacture parts from
beginning to end, from raw stock to
finished parts. We could no longer
depend on someone else to grind
parts to the schedule we needed,”
said Labrie. “We were at the mercy of
our supplier. He did a fantastic job but
had many other customers also vying
for his time. This is when we acquired
a CNC grinder to eliminate a lot of
those problems, and it did.”
Southampton, Massachusetts, precision machine shop acquired an
advanced CNC cylindrical grinder and realized wide-ranging positive
effects on work flow and delivery, part quality and machine utilization
along with production costs and quoting.
J&E Precision Tool, Inc. started in 1979 in a one-stall garage. Initially the shop
provided general commercial machining services, including toolmaking and
production of firearms parts and fixtures. But, it sought to take on higher-
precision work, specifically in the aerospace and defense industry sector.
Participation in the new markets grew from word of mouth, as did J&E’s
reputation for consistent on-time delivery of high quality parts. Expanding
business produced a need for more manufacturing space and equipment.
In 2001, J&E moved to its current 45,000-square foot facility and today employs
70 people as well as operates a broad selection of CNC equipment that includes
3-, 4- and 5-axis milling machines, 10 lathes, and a 7-axis milling and turning
center. J&E now serves customers across the United States in not only the
aerospace and defense markets, but also the microwave equipment industry —
a niche market that, according to Jon Labrie, general manager at
J&E Precision Tool, “has been growing like wildfire” for the shop.
36 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 37
CNC Grinding Launches
Shop'sAerospace and DefenseWork
Anybody can make the easy stuff ... our customers’
engineers continue to push the design and manufacturability
limits, and we embrace the challenge.
F E A T U R E
competitive pricing. The STUDER grinder also enables the shop
to take on jobs it would have had to turn down in the past.
J&E produces some parts small enough to require a
microscope for inspection. “We’ve drilled holes down to
0.0005" in diameter, and we’ve run end mills measuring just
under 0.0008" in diameter,” said Labrie. At the same time,
the shop also machines parts as large as 20" x 60" x 18".
Job lot sizes range from one to upwards of 2,500 pieces.
And at any given time, J&E can have a hundred jobs being
Adding flexible CNC grinding technology has affected
nearly every aspect of J&E’s production process. Grinding
capability and process control has facilitated the addition of
new markets and customers, higher part quality and reliable
delivery times, and lower costs. Labrie expects the progress
to continue; “We never stop looking forward,” he said.
After thoroughly researching available grinding technology,
J&E purchased a STUDER S33 universal cylindrical grinder
from UNITED GRINDING in mid-2013. The S33 processes
medium-sized workpieces in individual and batch production
and features one ID wheel and two OD wheels. Its
wheelhead has two motor spindles for external grinding as
well as an internal grinding attachment, which allows J&E
to grind complex workpieces in single clampings.
UNITED GRINDING helped J&E get up to speed quickly
with the new machine. “They came into our facility and
trained us for a week” Labrie said. “Then, after we ran the
machine for a while, they came back for another week once
we knew more about what we were doing and had more
With the acquisition of the STUDER grinder, J&E regained
full control of its grinding process. “If I want to put two
shifts on a part, I can. If I want to run over the weekend,
the machine will. That is huge when it comes to delivery,”
38 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 39
Use of the S33 grinder also enhances the shop’s ability
to maintain top part quality. Previously, some parts were
both roughed and finished on turning centers. Now, many
of those same parts are roughed on a turning center and
finished on the grinder.
“Not only are we getting higher quality parts, we are
getting them done faster as well,” said Labrie. “Plus,
replacing turning with grinding frees up our turning centers
to process other parts.”
From its work on aerospace and defense projects, J&E
is familiar with machining of high-performance materials
such as stainless steels, titaniums, nickel-based alloys
and aluminum. But what takes the shop to the next level,
according to Labrie, is grinding those materials.
When grinding exotic materials, he explained, choices of
wheel types, speeds and feeds and cutting fluids can make
a significant difference in final part dimensions and quality.
The shop occasionally resorts to trial and error to find
optimal grinding parameters, but the grinding knowledge
and experience of staff personnel usually produces the best
combinations of tooling and parameters. The machine’s
operators also program the shop’s grinding processes.
Creating effective grinding setups is another challenge.
Labrie said that setups occasionally involve “crazy stuff and
other unique fixtures” to hold parts because not all of them
are round and simple to clamp.
“With tight tolerances you don’t want to squeeze a thin-
walled part out of round, or push the process too hard, or
add stresses during grinding,” he advised. “And fixturing
is often the determining factor of whether or not a part is
acceptable once grinding is complete.”
Grinding parts in-house instead of subcontracting the
work positively affects the quoting process at J&E. Labrie
pointed out that quotes previously took into account
the subcontractor’s grinding charge, which included the
subcontractor’s overhead costs and profit margin. Now,
with the grinding performed in-house, those outside costs
are eliminated, and in turn, J&E can offer customers more
Not only are we getting higher quality parts, we are getting
them done faster as well ... plus, replacing turning with
grinding frees up our turning centers to process other parts.
40 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 41
D I G I T A L D I G E S T
through rates. And it works. A recent
study suggests that 25 percent more
consumers look at in-feed, native ad
placements over standard banner ads.
Use of native advertising is growing
rapidly. While companies marketing
to consumers have been using native
advertising for quite some time,
business-to-business marketers are
starting to see the benefits as they
become more entrenched in social
media and online marketing.
Here are some important things to
keep in mind if you want to use native
advertising tactics to drive business in
Provide Good Content
The best native advertisements deliver
useful information to the reader or
viewer. It gives them something
that will help them work better or
become more efficient or profitable.
The content you provide is a reflection
of your brand. If it is not well written
or not worth reading, you risk losing
credibility. Remember, you want the
reader to come back each time they
see a new ad from you.
While the premise of native
advertising is that it follows the same
format as the content around it in
order to blend in, the ads must still
adhere to certain guidelines when
it comes to designing and labeling
content. These types of ads, which are
paid-for advertising placements, must
be clearly identified as sponsored
content or ads.
Choose a Strong Headline
Most often, native ads are designed
to elicit the user to click to view a
video or read an article. But make
sure you pique their interest or
curiosity with a benefit-driven
headline. For example, if you post a
video showing how you’ve expanded
the grinding capabilities in your shop,
use a headline such as: Imagine What
You Can Achieve with Our
New Grinding Services.
CyClotron ProduCts, InC.
Visit our website: www.cyclotronproducts.com
Cyclotron Products, Inc. offers a complete line of filtration systems
designed to remove solid particles from water soluble and synthetic
industrial fluids using the most economical and efficient methods.
Leaders in Filtration Systems
• Extends coolant life.
• Up to 30% longer
grinding wheel life.
• No purchase of
replaceable filter media.
• Low maintenance costs.
• Small footprint.
• More parts per dressing cycle.
• Less machine downtime.
• Eliminates amount of
• Consistent coolant aeration
eliminates bacteria problems.
• Closer tolerances on
Cyclonic filtration benefits the environment as
no disposable media is used in the process.
This saves petroleum, preserves countless trees,
and eliminates the associated environmental
impact created by the disposal of spent filter media.
Contact us to discuss all of your filtration needs. (262) 898-0710 • Fax (262) 898-0748 • 1509 Rapids Drive • Racine, WI 53404
We see them every time
we look at our LinkedIn
or Facebook feed or
use a browser to search
the Internet. These videos, posts
and articles resemble and blend in
perfectly with posts from friends,
updates from professional connections
as well as our online search results.
But, what a lot of us don’t realize (yet)
is that this content is part of a growing
digital media trend called native
advertising. In other words, a highly
strategic form of online advertising
that mimics the content around it.
The goal of native advertising is similar
to other forms of advertising. After
all, it all boils down to creating brand
awareness and generating interest
in a company or product. The real
difference comes from how native
advertising looks and prompts the
audience to take action, such as click
to learn more or watch a video.
Native advertisements are presented
in the same format as editorial content
so they feel less intrusive to the target
audience. This is a strategy that was
developed in hopes of increasing click-
[ney-tiv ad-ver-tahy-zing] a form of online advertising that
matches the form and function of the platform on which it appears.
WHY USE NATIVE
• People prefer them.
70% of people want
to learn about products
through content rather than
• Drives purchases.
Native ads registered 18%
higher lift in purchase intent
than banner ads.
• Achieves brand goals.
97% of mobile media
buyers report that native ads
were very or somewhat
effective at achieving
42 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 43
ounded in 1978 in Akron, Ohio, Copen Machine has grown from a garage
job shop with a single manual knee mill into a full-service machining and
fabrication provider specializing in high-volume precision parts production.
And, for this demanding line of work, the company has carved out a unique
marketplace niche using Swiss-style lathes in conjunction with automated
cylindrical grinding operations.
Now located in Kent, Ohio, Copen Machine offers a comprehensive range of
machining services. Its major customers include those in the commercial food
processing, firearms and physical security industries. The company processes
a wide variety of materials, from steel and aluminum to plastic, titanium and
super alloys. However, stainless steel parts comprise the majority of the
The company has three facilities. The main plant houses CNC Swiss machining
and CNC cylindrical grinding. A second houses conventional CNC turning and
milling, and the third handles fabrication and manual machining.
Travis Copen, president of Copen Machine, pointed out
that the company’s strength is its high-volume CNC Swiss
machining. Its 18 CNC Swiss-style lathes continuously
produce annual part runs in the millions, operating six
days a week in an environment that could be considered
The transformation into high production came gradually at
Copen Machine. Early jobs included components for bank
vaults and ATMs. As parts grew increasingly more complex,
they required highly advanced machining processes.
In 1994, the company added CNC capability with a custom-
modified boring mill. With the new equipment came new
customers and additional equipment. Customer demand
for smaller precision parts in larger volumes prompted the
purchase of the company’s first CNC Swiss-style lathe in 2003.
As key customers continued to experience rapid business
growth, demand for the Swiss-machined parts accelerated,
creating a need for increased capacity. For instance, Copen
went from machining 100,000 parts a year for a particular
customer to more than a million a year.
About a third of parts produced on the Swiss-style machines
require precision grinding. The company routinely works with
a few reliable top-quality grinding subcontractors. However,
rapidly growing customer requirements for higher volumes
and quick turnarounds exceeded the capacities of these
As a result, Copen decided to bring some of the high-volume
grinding operations in-house. He thoroughly researched
advanced CNC grinders, focusing on those best suited for
automation. “To automate grinding is one thing,” said
Copen, “but to automate high-volume, tight-tolerance,
lights-out grinding is something else.”
Copen Machine decided on a STUDER S22 production
cylindrical grinder from UNITED GRINDING. The machine
offers a maximum grinding length of 800 mm and a center
height of 175 mm.
“We kicked the tires and liked the fact that the machine
was solidly constructed and fully enclosed,” said Copen.
“The enclosure is optimal for automation. Parts can move
in and out of the machine without having to open it. That
capability increases process consistency, which is the key to
successful unattended operations.”
Copen Machine worked with robotic integrator Matrix Design
Group for the S22 cell that consists of the grinder, a FANUC
ArcMate 100i robot and a gantry loader. The robot takes parts
from manually racked trays and loads them onto the gantry
that delivers the parts into the grinder.
Shop CombinesAutomated Grinding and Swiss-StyleTurning
F E A T U R E
Copen Machine specializes in
high-volume precision parts
production for the commercial
food processing, firearms and
physical securities industries.
“We needed the ability to load 1,000 parts at a time into
the machine so it would be able to run for a significant
number of hours,” Copen said. “The grinding and robotic
loading process can be below 30 seconds per part. Our lot
sizes for automated grinding range anywhere from 1,000 to
50,000 parts. For us, it’s not practical to set up an automated
100-piece run of basic OD ground parts.”
He added that the plan was to automate the grinding process
immediately with lights-out operations being the goal from
the start. The company replaced the standard coolant
filtration arrangement and instead installed a deep bed filter
to remove large amounts of material produced by continuous
operations. There is also a larger size mist collector that
features a high-efficiency particulate arrestance (HEPA) filter
to absorb mist that could negatively affect humidity and air
quality in the temperature-controlled facility. Key personnel
are also present in the plant to check on cell operation,
troubleshoot problems and pull parts for SPC inspections.
While the automated S22 added significant production
capacity, the prodigious output of the Swiss machines
outpaced the grinding cell. Consequently, Copen Machine
added two more STUDER Universal Grinders — an S31 and
S33 — and is in the process of automating both machines.
Part precision requirements at Copen Machine dictate
grinding strategies. Typical machining size tolerance is
+/- 0.0002". Grinding tolerances may be half that, surface
finish requirements as fine as 4Ra and roundness/cylindricity
tolerances are 0.000050" or better. Parts are machined from
bar stock as small as 0.125" in diameter. Some production
shafts exceed 12” long.
Tight tolerances and the possible flexing of longer parts
often require OD grinding between centers. Parts usually
feature multiple diameters and interrupted cuts. The shop
step dresses its grinding wheels to produce multiple
diameters. Interrupted cuts, on the other hand, pose a bit
more of a challenge.
“We run parts that require we hold both tight overall
tolerance as well as even tighter roundness tolerance. On
top of that, they may have an interrupted grind surface,”
Copen said. “To handle this, everything has to be right. It’s
impossible to grind over a milled flat and hold 0.000050" part
roundness unless you have a strong, solid machine. That’s
why we went with STUDER grinders. Their mineral-casting
bases are very rigid and provide optimum thermal
stability. At 18,000 lbs., the machines just do not move.”
The S22 grinder at Copen Machine features a 24"-diameter
wheel. The bigger wheel has a larger surface area and offers
greater life between dresses. Copen said a company which
is interested in high-volume CNC grinding should consider a
machine with a larger wheel. He added that he always avoids
using machines that have anything less than a 20" wheel.
Copen Machine uses aluminum oxide wheels and dresses
them with rotary diamonds on the S22 grinder and with
stationary diamonds on the other two STUDER machines.
There is virtually no dresser wear.
Careful dressing techniques are necessary because the 630
stainless steel that is the company’s mainstay workpiece
material will quickly load up any wheel explained Copen. He
added that the steepest learning curves involve selecting
the proper wheel, finding a feedrate conducive to grinding
gummy stainless steels, then establishing dress frequencies
that will maximize process reliability.
Copen Machine develops reliable parameters through
comprehensive testing — first trying different grinding
“We run parts that require we hold both tight overall
tolerance as well as even tighter roundness tolerance.
That’s why we went with STUDER grinders.
44 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 45
“We don’t automate to eliminate jobs.
We do it to increase capacity and enhance
job opportunities. Automation takes the
pressure off our machinists so they can
focus on quality.”
wheels, then tweaking the process through continuous
improvement. “You have to be very patient when grinding,”
Copen said. “You take small controlled steps and document
everything that you do. You have to dim the lights before
going completely lights out with grinding.”
Copen added that maintaining a customer’s desired part
surface finish is to a large degree determined by the grinding
feedrate and dressing frequency, which also affects wheel
life. “If you grind too fast, you are going to load the wheel
and need to dress it more. On the other hand, if you grind
more slowly and less aggressively to prevent wheel loading,
you are going to burn the part surface,” he said.
Once he has determined appropriate grinding and dressing
parameters, Copen relies on STUDER integrated software
that provides modules for wheel contact detection and
automatic wheel balancing along with other functions that
ensure trouble-free grinding. Additionally, the software aids
in automated operations through monitoring of wheel wear
and the condition of machine components. Because many
of the parts that the company grinds are similar, Copen
Machine stores, then slightly modifies grinding programs
whenever possible to keep part changeovers typically well
within two hours.
All three of the shop’s STUDER machines have in-process
gauging that is especially valuable on long production runs.
Copen noted that in the company’s high-volume environment
the carbide contacts of the in-process gauging system
exhibited rapid wear. Installing diamond contacts remedied
Their mineral-casting Granitan bases are very rigid
and provide optimum thermal stability. At 18,000
lbs., the machines just do not move.”
Continuous preventive maintenance, according to Copen,
is imperative when it comes to high-volume, lights-out
automated grinding operations. “You can’t skimp on routine
maintenance because machines are only as reliable as you
keep them,” he said. “Diligent preventive maintenance
comes with a cost, but it is something you must do.”
Maintenance activities include daily inspection for dirt and
sludge buildup and overall cleanliness of automation grippers
and machine coolant. Proper coolant pressure and fill levels
are also inspected. Weekly checks should cover automation
belts/conveyors and other components, while monthly
checks focus on machine lubricants and hydraulics.
Copen pointed out that preventive maintenance is a team
effort, with operators performing some of it on a daily basis.
“The key is cross training at every level. The automation
dictates the volume of production we are able to get, and the
maintenance helps us to achieve it.”
Smooth running, trouble-fee automation provides high-
volume throughput along with process and part consistency.
“Automation has added about 35 percent to our existing
capacity,” said Copen. “We don’t automate to eliminate jobs.
We do it to increase capacity and enhance job opportunities.
Automation takes the pressure off our machinists so they
can focus on quality.”
In addition to producing high volumes of top-quality parts
quickly, Copen Machine has established procedures that
enable it to meet demanding customer delivery requirements,
including shipments within 24 hours and servicing of Kanban
systems. Copen said, “It comes down to the ability to produce
high-quality components consistently. You can make a million
good parts in our niche of the business, but one bad part can
cost you a customer.”
By Doug Kranz,
Vice President, Sales and Marketing,
FISCHER USA, Inc.
chieving maximum productivity and profitability
when externally grinding cylindrical workpieces is a
challenge on its own. Grinding internal diameters,
however, poses additional challenges, including
problems clearing swarf and difficulty controlling heat
generated in the basically enclosed ID grinding process.
The grinding spindle is a key component in successful
grinding operations. Spindle speed capacity is one of the
most important features of an ID grinding spindle. Achieving
high grinding speeds necessitates application of direct-drive
spindles. For ID grinding of small-diameter bores, the spindle
must be able to rotate a small wheel at a surface speed
sufficient to produce good grinding results. For example, an
operation such as finish grinding of diesel fuel injectors with
a 3-mm diameter grinding wheel will require spindle speeds
in excess of 120,000 rpm. Inadequate spindle speed when
grinding small bores will cause increased grinding forces,
reduced material removal rates, poor part surface finish and
accuracies, and overall reduced grinding performance.
Advanced spindle technology is needed to achieve the high
spindle speeds required for internal grinding. The spindle
bearings should be as large as possible in order to support
the largest diameter spindle shaft. This will maximize
spindle rigidity, which is a requirement for high-accuracy
grinding. However, this means that the bearings must run
at extremely high speeds. Advanced bearing and spindle
design and advanced lubrication techniques are required to
achieve these high bearing speeds. The rotor of the internal
motor must have a sufficient diameter to produce ample
torque for grinding operations throughout a wide speed
range, and must also fit the largest spindle shaft possible.
This requires advanced shaft and rotor design to remain
stable and well balanced at top speed, withstanding the
high centrifugal forces produced at high rotational speeds.
The size of the grinding wheel is another major factor in
ID grinding productivity. A wheel that is too large will not
generate sufficient pressure to cut effectively and will
quickly become dull. In addition, an overly large wheel will
impede coolant flow, raising temperatures in the grinding
zone and interfering with swarf removal. On the other hand, a
wheel that is too small grinds inefficiently because it presents a
relatively small amount of abrasive to the workpiece. Excessive
pressure that results from the use of an undersize wheel will
accelerate wheel wear and increase load on the spindle.
For internal grinding, the ideal wheel has a diameter that is
about 70 to 80 percent of the intended bore diameter. For
very small holes, it may be necessary to apply a wheel that
represents a greater percentage of the bore diameter.
Grinding wheels should be free cutting and generate as little
heat as possible, because the enclosed nature of ID grinding
traps and sustains heat in the grinding zone. Accordingly,
comprehensive cooling of spindle components is crucial. A
spindle should feature separate liquid cooling circuits for front
and rear bearings as well as for the spindle motor itself. Spindle
bearing lubrication, another thermal management factor,
generally is an oil/air mix provided by direct injection.
Cooling the wheel/workpiece interface is equally essential.
High-performance grinding spindles feature coolant-through
shaft unions that deliver coolant directly to the grinding zone.
They do so at pressures upwards of 30 bar to effectively cool
for spindle speeds up to 180,000 rpm.
Rigid support and smooth operation of spindle bearings
enable consistent production of required part surface finishes.
Bearings typically perform for 15,000 to 25,000 hours before
needing overhaul. However, grinding fluid, high temperatures
and swarf that make up the hostile grinding environment can
contaminate bearings and shorten their lives exponentially.
Top quality spindles have labyrinth seals combined with an air
curtain ring at the interface of the rotating shaft and stationary
housing to prevent contaminants from entering.
The ID grinding spindle must be as short and stiff as possible
to resist forces of grinding and compact enough to best utilize
the limited machine workspace available. Mounting the grinding
wheels on tungsten carbide quills will also enhance stiffness.
The quill should be as short as possible; in general, a quill with
a length/diameter ratio of 3:1 or less will provide sufficient
rigidity for ID grinding. Conversely, when the length-diameter
ratio is equal to or greater than 6:1, problems involving chatter,
deflection and taper of the ground part can arise.
Workholding is another area where ID grinding prompts special
considerations. ID grinding is not performed between centers,
so workpiece clamping has to present the part in perfect
alignment with the grinding spindle to assure concentricity.
The clamping arrangement must hold the workpiece securely
but not distort it, a task that may be difficult when internally
grinding thin-walled parts.
Aside from the spindle technology, the most important
contributors to long and effective spindle life are the machine
operators. It is essential that those who run the grinding
machines receive sufficient training and develop full awareness
of the factors that affect spindle operation. Knowledgeable
operators, combined with advanced spindle technology, can help
a shop get the best out of its ID grinding operations.
46 Grind/Grinding Universe Issue 2015 Grind/Grinding Universe Issue 2015 47
F E A T U R E
Advanced Spindle Technology
Tackles ID Grinding
The grinding spindle is a key component in successful ID grinding operations.
Tool-tip concentricity and overall stiffness are essential because ID grinding
places increased axial and radial forces on the spindle.