ShopSolutions
Case Histories of Manufacturing Problem Solving
Modified Vises Put Clamps on Product Changeover
C
ox Machine Inc. (Wichita, KS) has adopted a new
forward thinking, treating suppliers as partners, and focusing
workholding setup for machining 44 different parts
on cellular manufacturing. We plan ahead during the quoting
continuously without requiring changeover. Quanti-
phase, designing new cells like this Kurt-equipped cell, and
ties and sizes for the aerospace
structural components range from
the size of a deck of cards to a 6"
(152.4-mm) vise. Previous setup
methods on a pair of Haas VF-2YT
machining centers took up to an
hour per job.
“With the new workholding
process featuring a modified Kurt
D688 and 3630H vise, productivity and quality improvements are
substantial for the two-machine
cell that operates continuously two
shifts, seven days a week,” said
Jason Cox, chief technical officer.
Cox Machine was founded
in 1954 by Jason’s grandfather,
Ernest “Bud” Cox. Based on his
experience as a machinist at
Cessna Aircraft and Kansas Tool,
Cox decided to open his own ma-
Paul Perales, machinist at Cox Machine, is holding an aerospace component
machined on one of the two Haas VF-2YT machining centers equipped with
customized Kurt workholding in the cell.
chine shop to serve nearby Wichita aerospace manufacturers.
work with suppliers as partners, allowing us to reduce cost
Now in its second generation ownership, Cox Machine has
through the entire supply chain from raw materials to tooling
two facilities, an ultra-modern 80,000 ft (7432 m ), climate-
purchases to vendor-owned inventory,” said Cox.
2
2
“A three-step lean strategy approach puts us ahead of our competition
and this workholding design is an ideal example of that lean strategy.”
controlled facility specializing in cutting edge machining and a
“All of the 44 different aerospace structural components
separate 24,000 ft2 (2230 m2) facility specializing in sheet-
are machined from pre-cut 7050-T74 aluminum blocks. A
metal fabricating. Cox Machine’s customer list reads like a
needed part size is loaded into the first machine for machin-
“Who’s Who” of aerospace manufacturing with companies like
ing one side of a specified part including a special dovetail
Boeing, Cessna, Spirit, and Vought, to name just a few.
feature. This dovetail positions and holds the part in the
“A three-step lean strategy approach puts us ahead of our
second machine and is removed after machining. The second
competition and this workholding design is an ideal example
machine is equipped with an indexing table and a different
of that lean strategy,” said Jason Cox. “The three steps are
hydraulic setup to allow for tapping and machining all sides of
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Shop Solutions
the parts not done on the first machine.
The indexer is required because parts
have features that must be machined
from the side or at an angle,” said Cox.
“This was the first time we designed
a setup like this using a D688 vise with
a hydraulic cylinder,” said Michael
Granlund, Kurt custom workholding
designer. Compared to using standard
vises, the change to the Kurt vises
with custom modifications has greatly
reduced upfront costs and future maintenance costs, eliminated setup time,
reduced part runtime, reduced scrap,
and increased part quality.
The Kurt D688 vise with modified hydraulic actuation has no screw mechanism.
“The workholding setup using a
It is mounted on the machine table for machining one side of the components.
D688 vise has a body modified at the
The hydraulic cylinder positions the vise jaw forward and reverse to handle all
end opposite the stationary jaw for
44 part sizes.
mounting the hydraulic cylinder. There
3054-4088-ME_1114-4.56x4.88-2C.eps 1 9/29/2014 7:14:14 AM
is no screw in this vise. The vise nut
was custom designed with a drilled and
tapped hole in the end of the hydraulic
cylinder rod. A double-acting, custom
length hydraulic cylinder is used with
a demand-type hydraulic pump. This
allows actuating the cylinder forward
and reverse through a directional control
valve to handle all 44 different part
sizes,” said Granlund.
C
The first machining operation done
M
in the D688 vise machines half of
Y
the part along with a dovetail, half-
CM
moon-shaped feature which aligns the
MY
part for the second operation in the
CY
modified jaws of a 3630H vise. All parts
CMY
have the dovetail width so the second
K
operation requires no setup from part
to part. Dovetail length varies with the
size of the part.
The second machine setup with the
3630H hydraulic vise is mounted on an
indexer and has custom dovetail jaws.
The dovetail jaw on the stationary side
has a half-moon dowel locator for correct positioning of the parts following the
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December 2014
Shop Solutions
first machining setup. This indexer allows for full 360° rotation
and stationary jaws to stabilize the larger parts. Like the first
when needed to tap, drill, and finish all sides of the part. A hy-
machine setup, this one runs all of the 44 different-size parts.
draulic connection runs through the center of the indexer with
Both machine setups operate from the same hydraulic power
a rotary union. This setup has rest buttons on the movable
unit at 2000 psi (13.8 MPa).
“Our long-term plan for this setup is
to integrate a robotic loading system to
make it even more efficient,” said Cox.
“As it stands, we’re very pleased with the
cell setup and the increased productivity.
The workholding from Kurt worked just
as expected right out of the box.” ME
For more information about Kurt
workholding, go to www.kurtworkholding.com, or phone 877-226-7823; for
more information about Cox Machine
Inc., go to www.coxmachine.com, or
phone 316-943-1342.
Coolant-Through
Retrofit for Deep
Crosshole Drilling
C
olumbus Hydraulics Co. is a hydraulics cylinder designer and manufac-
The FVM-104160DC is perfect for lean, repeatable mass production of large and
heavy workpieces. The slanted Y- and Z- axes increase the slideway surface and
eventually distribute the load in the area.
The series also features these benefits:
• The FVM double-column VMC has an extremely rigid and stable structure base
on oversized columns, extra-wide spacing of box ways on a slanted Y-axis and a
close symmetrical design of the Z-axis.
• The four heavy-duty linear roller ways of the X-axis support the table and boost
moving speed, dramatically reducing stick-slip problems caused from box ways
machines and increasing the machines positioning accuracy.
• The XY-axis runs with a Class 3 high-precision, double-nut, pre-tensioned ball
screw. The coolant circulation in the 3" large balls crews eliminates thermal building and ball screw deformation, helping to maintain high-positioning accuracy
and repeatability.
• The 50-taper, cartridge-type, air-purge, 6000rpm with 30 HP spindle is driven
by a two-speed gearbox with low speed for extra-high torque output during heavy
cutting. It generates a maximum torque of 449 ft.-lbs.
Think versatile. Call your Chevalier dealer today to learn more about the
FVM-104160DC and see you at Houstex.
turer for applications ranging from fire
trucks to agricultural equipment, railroad
track laying systems to earth-moving
machinery. Since 1952, the company
has mastered a number of challenging
part-machining operations. The company’s most recent mastery, deep crosshole
drilling, however, is one that typically
attracts the least amount of attention.
The Columbus, Nebraska-based shop
drills deep crossholes measuring anywhere from 0.125 to 1.250" (3–31 mm)
in diameter and usually through 2.5–3"
(63–76- mm) diameter parts made from
tough 1018 and 1141 carbon steel bar
stock. To further complicate the process,
the primary machine tool used—a large,
SEE US AT HOUSTEX IN BOOTH #262
800-243-8253 / 562-903-1929
www.ChevalierUSA.com
We shape your ideas.
CMI_mfg_eng_FVM-104160DC_half pg_4clr.indd 1
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horizontal CNC turning center with milling axis—often lacks sufficient space for
unrestricted tool maneuverability when it
comes to several of the shop’s crosshole
10/20/14 3:32 PM
drilling operations. This meant additional finish
operations on other machines to produce the
necessary features.
While using shorter custom-made carbide
and dual-inserted drill bits partially solved the
tool maneuverability problem and eliminated
extra operations, inadequate coolant delivery
created another obstacle. The machine’s standard flood coolant worked in most operations,
but it fell short with deep crosshole drilling.
“For our crosshole drilling operations, we
have to keep coolant directly at the tip of the
drill, or it will burn up from the generated heat,”
said Pete Hayward, Columbus Hydraulics CNC
Rego-Fix’s reCool retrofittable coolant-through system delivers coolant to
the tip of the drill where it does the most good for deep crosshole drilling
at Columbus Hydraulics.
supervisor/programmer. “Flood coolant had always been fine for
While through-tool coolant delivery offers multiple benefits
our other hole-making operations. So, at the time we acquired
that boost productivity and tool life, live tooling heads with
our CNC horizontal turning center, a dedicated through-coolant
the capability, according to Hayward, can be a substantial
head just didn’t seem necessary,” said Hayward.
investment. With that said, live tooling with through-coolant
DID YOU
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to produce the required tolerances
+ Higher Performance: Licensed tooling provides the benefits of higher rigidity,
accuracy and repeatability
+ No Risk: Reverse-engineered alternatives can possibly damage spindles
due to an improper relationship of taper-to-flange face
HIGHER PERFORMANCE. GUARANTEED.
Stay in the know at bigkaiser.com/toolholders.
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11/5/14 10:08 AM
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Shop Solutions
capability made little fiduciary
sense for Columbus Hydraulics,
whose operations have only a
minimal need for through-coolant
delivery. What did, however, make
good economic sense was a new,
retrofittable through-tool coolant
system from Rego-Fix Tool Corp.
(Indianapolis, IN).
The system, called reCool,
allows shops, such as Columbus
Hydraulics, to quickly, easily, and
cost-effectively upgrade live tooling heads from standard externalcoolant to through-tool coolant capability. reCool consists of only five
Columbus Hydraulics drills deep crossholes measuring anywhere from 0.125 to
components—a special clamping
1.250” (3–31 mm) in diameter and usually through 2.5–3” (63–76-mm) diameter
nut with outer ring, a sized sealing
parts made from tough 1018 and 1141 carbon steel bar stock.
disk, coolant pipe, straight fitting,
and elbow fitting. Provided that the live tools have an ER
collet system, reCool can retrofit onto existing straight and
angled live tooling heads in as little as two minutes.
reCool keeps coolant constantly pinpointed at the cutting
tool’s edge and precisely in the cut zone to evacuate chips
and reduce heat, which, in turn, helps extend tool life and ultimately shorten part-machining cycle times. In deep-hole drilling, for instance, these systems eliminate the time-consuming
peck cycle style of operation for removing chip build up in
the machined holes that can lead to tool failure. In addition,
because through-tool coolant controls heat better, shops can
generate better hole surface finishes and drill at much higher
speeds and feeds without the risk of premature tool wear.
Through its clamping nut, reCool diverts the tooling head’s
external supply into the collet holder cavity. This function
prevents coolant from seeping back into the internal compartment of the live tooling head. Such seepage is what leads to
the maintenance issues typically associated with dedicated
through-coolant heads.
The reCool clamping nut requires only a sealing disk, also
obtained from Rego-Fix, that is sized to the shank of the tool
used, making it and the entire system maintenance-free for Columbus Hydraulics. The sealing disk clips into the clamping nut
above the collet forcing the coolant to flow through the cutting
tool instead of out of the collet face. During system operation,
machine tool coolant fills a small gap between the reCool’s
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December 2014
rotating component and the mating stationary nut. Once the
we can crossdrill as many as 300 pieces with those particular
gap is full, a liquid bearing forms and reduces friction and dis-
drills, then have enough tool life left to drill short pipe-tap holes
sipates heat caused by system rotation. It also maintains lower
in another 200 or so pieces.”
operating temperatures to preserve internal components.
Continued on page 70
reCool works with basically any level
of coolant pressure as long as the coolant
is filtered and a strong consistent flow is
maintained. Also, during reCool operation, a machine’s coolant system experiences no loss of pressure. Because reCool uses coolant as a bearing, the only
other key system requirement is that the
machine tool’s coolant must be switched
on and flowing prior to starting a cutting
The EBC110 Precision
Boring Mill provides a
new level of accuracy,
rigidity and reliability
for under $350,000.
tool’s rotation in the live head.
Columbus Hydraulics immediately
began reaping the benefits of the reCool
through-tool coolant delivery. Since retrofitting the system to its CNC turning center, the shop has been able to maintain
a steady supply of coolant directed precisely to the cutting tips of drill bits. This
not only enhances the cross drilling operation, it allows the shop to drill straight
through without stopping or having to run
a pecking routine. In addition, since the
reCool retrofit, drilling cycle times have
dropped from upwards of three minutes
per hole to only 45 seconds at most. And
there have been significant improvements
in hole surface finishes as well.
“The reCool system has taken our
surface finishes from adequate to world
Engineered in Germany, the EBC110 features a 50 Taper coolant-thru 3,000RPM
spindle with a heavy-duty gearbox for high torque and a precision 49" x 55"
full 4th axis rotary table capable of holding 11,000 lbs. The box way design,
Heidenhain scales, 40 position tool changer, chip conveyor, sheet metal
enclosure, air-conditioned electrical cabinet, and the FANUC 0i-MD control make
this boring mill perfect for large part machining.
class,” Hayward said. “And while these
aren’t quite the same level of surface
finishes achieved with boring or reaming, they are well above average for
simple drilled surfaces.”
SMTCL offers over 300 different machine models, including dozens of models
of table and floor type boring machines. Our California-based team and network
of local distributors provide the applications engineering and service support
that you demand. Call or visit our website to see how SMTCL can deliver for you.
Columbus Hydraulics continues to
be most impressed with how reCool increases its tool life and helps boost overall productivity. “Even with solid carbide
drills, we used to run only 100 pieces
www.smtcl-americas.com
626-667-1192
before the drill would burn up,” said
Hayward. “Now, with the reCool system,
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Shop Solutions
Continued from page 47
Though larger deeper crossholes make up a comparatively
tolerances,” said Markus Petschnig, managing director. By
small percentage of Columbus Hydraulics' average workload,
working with Jenoptik Industrial Metrology Division (Peseux,
the shop incorporated additional CNC turning centers to help
Switzerland), Polymeca has managed to combine maximum
handle orders that require the large-diameter drilling opera-
machining precision with highly efficient series production.
tion. Like its first turning center, the shop has also retrofitted
additional machines with a reCool system.
Grinding axle systems for theodolites is one of the most
challenging of grinding tasks. After all, the measurement
accuracy of these instruments, which are used for measuring
angles and work with GPS, is dependent on the precision of
the rotary and tilting axles. Polymeca AG has been manufacturing high-precision axle systems of this type for more than
20 years using conventional grinding machines.
The company which has a long tradition has now written a
new chapter in precision and process reliability. It has paved
the way for introducing incredibly efficient and cost-effective
production processes by building an innovative manufacturing
facility. This facility consists of four fully automated precision
grinding machines for internal and external machining with up
to triple match grinding. “By investing four-million Swiss francs
in a production and logistics facility perfected to our needs, we
have managed to halve throughput times, increase capacity by
Columbus Hydraulics' key personnel: Todd J. Duren, VP
sales and plant operations; Kevin Ainsworth, production
manager; Peter Hayward, CNC supervisor, programmer.
“When an order requiring us to drill several of the large
35%, and reduce stock values by 20%,” said Petschnig.
The most important effect of the new production line is the
process reliability achieved in large-scale series production,
with a machining accuracy of up to 0.001 mm guaranteed
even on untended shifts at weekends. This has been made
holes comes through, we have to be able to run them,”
possible by Movoline, the new generation of process metrol-
Hayward said. “So, now we have multiple turning machines
ogy from Jenoptik Industrial Metrology Division. Integrated di-
for performing the operation and three reCool units. Like the
rectly into the production plant, this solution makes automatic
first machine, dedicated through-coolant heads for every
trend corrections with the result that it can ensure a high level
live tool station would have involved significant cost. But in
of automation by controlling the grinding process of the axles.
this instance, we immediately opted for live tooling without
The rotary and tilting axles are given their final shapes—ac-
through-coolant capability we could retrofit Rego-Fix units for
curate to the micrometer—in the four precision grinding centers.
considerably less money.” ME
To make sure this can be done even on untended shifts, the
For more information from Rego-Fix Tool Corp., go to
www.rego-fix.com, or phone 317-870-5959.
machines are loaded with 960 unmachined shafts on workpiece
transport pallets. The appropriate match parts are also kept on
these pallets. Specially designed feeders grip the match parts—
In-Process Gaging Supports
Grinding at the Limit
S
wiss company Polymeca AG enjoys an excellent reputation within its industry for precision grinding. At its head-
for tilting axles, these feeders are two bearing flanges and a
circular carrier—and feed these parts into the three pre-process
devices set up for this purpose on a rotary table.
As the inner diameter of the ring is being measured, the
unmachined shafts are transferred to the grinding machine
quarters in Heerbrugg, it manufactures products such as axle
and are monitored by means of in-process measurements
systems for theodolites with press fits that have an accuracy of
during the machining process. The measurement results for
up to 0.001 mm. “In fully automated grinding centers, sophis-
each internal diameter are used directly in adaptive machin-
ticated process metrology is required to achieve these narrow
ing of the axle. This unique example of triple match grinding
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ensures that the axle will fit three other components precisely
using the same measuring device. Roundness checks and
at three different points. The axle is ground in a single cycle
length measurements are also completed at this point. These
while clamped between two parallel profile disks at a precision
checks are carried out for quality-control purposes, as well as
of up to ±0.0005 mm. The parts are then laser-marked and
for statistical process control and for readjustment or for trend
transferred as an assembly.
correction to compensate for thermal influences, grinding disk
Process metrology in the form of pre-process, in-process,
and post-process measurement procedures is used to achieve
wear and the like.
Petschnig also believes there is another advantage: “By
this exceptional level of precision in fully automated series
combining in-process and postprocess measurements in a
production. Here’s how:
single measuring device, no additional postprocess station is
First, pre-process measurements in match and triple match
required and efficiency is increased as no additional loading
grinding are used to determine the exact target values for ma-
of parts is needed.” When it comes to operating and display-
chining the axles. The pre-process measurements of the bearing
ing all measurement control functions in the entire facility,
flanges and circular carriers in the grinding centers at Polymeca
Hommel-Movomatic ESZ400 measurement and display in-
are taken using high-precision pneumatic Hommel-Movomatic
struments represent state-of-the-art installation solutions that
measuring arbors from the Jenoptik Industrial Metrology Division.
meet the toughest requirements.
This enables inner diameters to be measured in flexible and costeffective process, as well as at fast cycle times.
“We have actually always used Hommel-Etamic or Hommel-Movomatic process metrology, which is now provided by
Jenoptik through the Movoline product ranges,” said Petschnig.
“We were also impressed by the state-of-the-art digital technology featured in the new generation of in-process measuring
systems that we use in our new manufacturing facility. This
technology is not offered by any other manufacturer.”
Petschnig said that a crucial advantage of digital data
transfer is the fact that, in comparison to conventional analog systems, the measurement results are transferred free of
interference regardless of the cable length, and even under
the toughest conditions. In addition, the fieldbus technology
reduces the number of connection cables required, keeping
installation and maintenance work for the in-process measurement components to a minimum and thus also lowering total
Two measurement steps in one clamp: Hommel-Movomatic
DM200 and DP200 measuring heads for in-process measurement and subsequent post-process measurement
during grinding of theodolite axle systems.
For the in-process measurements, Hommel-Movomatic
production costs.
Besides enabling digital measurement data transfer, the
new generation of measuring heads allows a significantly more
compact design to be used. This allows measurement layouts
to be implemented such as those in the Polymeca grinding
centers where, depending on the axle type, up to five in-
DM200 digital gage heads and Hommel-Movomatic DP200
process measuring heads for diameters and an axial position-
digital axial positioning heads have been installed. These
ing head have been combined within the tightest of spaces.
heads allow reliable measurements to be taken of outside
“Initially, people find it hard to believe that we are achieving
diameters and passive axial positions, even under the most
unrivalled machining accuracy of up to one micrometer in a
unfavorable machine conditions. External influences on the
fully automated, large-scale production process using Hommel-
grinding process can be minimized as a result to ensure high-
Movomatic process metrology from Jenoptik. But we prove it
precision machining.
works 24 hours a day, seven days a week,” said Petschnig. ME
Immediately after the grinding processes are complete,
postprocess measurements are taken in the grinding machine
For more information from Jenoptik Industrial Metrology,
go to www.jenoptik.com/en, or phone 248-853-5888.
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