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Retrofit of a P&W machine with MachineMate control
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M
ACHINE
M
ATE
Retrofit Kit
For Pratt & Whitney Teammate Control


Mark Rice, based in Bedford, Texas, was a service representative for Pratt & Whitney machines
from 1978 to 1984. This was during the oil boom when most of the machines with the Teammate
control were built so he had personal experience with many of them. These machines are still in
production although their maintenance became difficult. Not only was the control about 20 years old,
but also its service was virtually impossible (since the support for the P&W controls had changed
after several mergers so good service often required finding someone who used to work at P&W).

Mark expected that an easy plug and go control retrofit could help many of these Pratt & Whitney
machines return to production quickly and with the knowledge that future maintenance will be easier
and less expensive. Younger operators are typically baffled by the old control. They simply cannot
relate to it and usually do not want to learn how to operate it. Mark intended to bring in a PC-based
M
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control that would be familiar to the entry-level workers since most of them know how
to work Microsoft Windows. The new control is todays technology with the full range of support
offered to a PC.

Pratt & Whitney had standardized their connections on many of their controls. For M
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retrofits on their machines, Mark was most concerned with the Teammate control (with a slope top)
and the Teammate II control (an upright control with a plasma display). Both used the TI 960 mini
computer for the control processor. Pratt & Whitney had also used several other vendor controls but
the two Teammate controls are the target for this kit. The Pratt & Whitney TriMac XV machine with
its Teammate control is shown below, before the control retrofit.



Retrofits of the known P&W machine configurations can be made very quickly. The complete
procedure for the control retrofit and then checking the machine and control for their return to
production can be completed in just a few days. All connections from the CNC to the machine tool Retrofit of Pratt & Whitney Teammate Control with MachineMate

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were made via Cannon connectors. These connectors are shown in the picture below, in the old
control. This control retrofit is compatible with both P&W lathes and mills.



Machines with customer options should require no special wiring but they will require the
development of the additional PLC logic to interface the option to the control. All input and output
signals will be available for the base machine and most options.












The inside of the M
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cabinet is shown in the picture at the above left (taken during the
control wiring phase). The back of the CNC is visible at the top (the industrial PC is the stainless
steel enclosure, mounted on the back of the color display) and the M
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IO modules are Retrofit of Pratt & Whitney Teammate Control with MachineMate

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mounted on a sub-panel in the lower center of the cabinet. The connector plugs for the wiring to the
machine are mounted on the left side within the cabinet. The DC power supplies are mounted on the
right side of the cabinet, above the IO modules. Extra I/O can be added (if needed) with another
MMIO module on the bottom of the stack. The AC isolation rack, with a number of breakers and
fuses (shown in the picture above right), is mounted on the back of the MMIO sub-panel and is
accessed from the door in the front of the cabinet, just below the keyboard.

Pratt & Whitney called their feedback devices quantizers that were 12-15 volt single-ended
feedback signals. Upgrading to encoders is recommended but an interface with the existing
feedback devices is possible. Mark has developed a level shifting interface circuit that can convert
these single-ended signals to the quadrature line driver signals compatible with the M
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encoder interface. There are two benefits to upgrading to encoders: the new encoder devices are
more reliable and the M
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can detect a feedback failure with the new devices, which it will
not be able to do with the old quantizers. The replacement of the encoders will add a little more time
to the schedule mentioned above because their wires will have to be routed through the machine to
the control. They also add to the retrofit cost since an encoder with the coupling and connector plugs
that are bolt-in replacements is approximately $500. Also, new encoders can be obtained with finer
resolution than the original devices providing better positioning feedback and smoother machining.

The replacement control with the M
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M
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is shown
at the left. The handheld operator station with MPG is
shown hanging on its bracket on the left side of the
cabinet. The door to access the breakers and fuses is
visible below the keyboard/mouse panel.















This customer chose to install an Ethernet network card in the M
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. The operators can
write and edit the part programs on the control but with the network connection they can also get the
technical details and scheduling information for the parts themselves from the parts customer. The
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control can run part programs from its internal memory but often the operators run the
programs directly from the hard drive, with a much larger program capacity than found in the older
memory-bound controls and with no practical limit on the size of an individual part program file.

Within one week after the installation, this customer had written and was running part programs for
parts that could not be run with the old control. Also, the work offsets (G54-G59) will save the
operators about one-half hour in setup time because they can save and recall the work offsets rather
than having to indicate the part again for each position. The canned cycles allow parameters like the
reference plane to be changed between each cycle position so the program can avoid the clamps
that could be an obstacle between certain holes.
Retrofit of Pratt & Whitney Teammate Control with MachineMate

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Below is the new M
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control in its cabinet next to the original Pratt & Whitney Teammate
control. The new Teammate control in 1977 cost approximately $50,000. The new control cabinet
with the options shown is $23,000. In adjusted dollars, this is one-ninth the cost of the original
control.






Before

After

This is an easy plug and go retrofit package, allowing the removal of the old control and its
replacement by a new control cabinet, with the machines old connectors being reattached within the
new cabinet. The retrofit whose pictures are in this article took just six working days. That time
included replacing two ball screws, a quill and a new spindle drive, in addition to replacing the
control.

If you need more information about the P&W retrofit kit please contact M
ACHINE
M
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Inc using any
one of the methods (phone, fax, email) listed at the end of this article.

Mark Rice has accumulated experience in all facets of the machine tool industry. Mark has worked
with machine tools from a number of vendors as well as many CNC controls and several PC motion
control cards. M
ACHINE
M
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Inc supplies a family of premier PC-based CNC products. The use of
Windows NT, a standard Pentium motherboard, standard PC components, an IEC-1131-3
conformant integrated soft PLC, the capability of Ethernet and standard field bus systems and the
support for either analog or SERCOS drives give this CNC package the utmost flexibility and
openness available today.

The individuals and companies mentioned in this article.

Mark Rice
Bedford Industries
824 Savannah Way
Bedford, TX 76022
Tel: 817-675-4313
Fax: 817-283-6233
E-mail: ricemark@comcast.net
M
ACHINE
M
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,

I
NC
.
100 W. Larsen Drive
Fond du Lac, WI 54937
Tel: 920-907-0001
Fax: 920-907-0181
E-mail: info@machinemate.com
Web: www.machinemate.com