When I think of current toolroom operations, I’m reminded of a
cartoon image showing an extremely modern factory. There are guided
vehicles buzzing around; robots with vision are loading machines; and
sensors of every sort are watching, checking, gaging, and testing.
Everything is slick, polished, refined–except off in one dark
corner, where a caveman is swinging a large club. He’s setting
It’s not quite that bad, but in the course of our travels, we
often encounter tool-control systems that contrast the sophistication of
the plant almost that much.
It’s surprising to find shops spending top dollar on the
latest CNC equipment, only to waste it with such outdated tool-control
practices. The toolroom–one of the last parts of the shop to be
critically examined–presents real opportunities to improve efficiency
and control for plants of every size. In this article, I’ll
examine how to update your toolsetting, tool control and tool handling;
we’ll explore the concept of toolroom automation.
What is toolroom automation? It’s much like any other type of
automation. By applying “systems” to specific tasks, we make
many operations automatic. In the toolroom, there are many ways to
apply such systems.
You can keep track of tools using a computer. Using a
“smart” toolsetting gage, you can automatically move the gage
to the tool point. You can automate tool handling, inventory, and
delivery in much the same way other parts of a shop are automated.
Granted, toolroom automation requires more flexibility than a
high-volume manufacturing system, but the technology to implement this
has existed for some time. It’s much the same as that technology
required for effective machining cells, FMS, and factories of the
In a nutshell, toolroom automation is how to bring tool-control
procedures into step with the rest of modern manufacturing. Why
automate the toolroom function? Nobody invests in automation for the
sake of automation. There must be concrete advantages–either short
term or long term. In the toolroom, there are several important ways
automation pays dividends.
Better toolroom operations improve tool-setting accuracy and help
ensure use of specified tool geometries. With automated toolsetting,
greater consistency is achieved, but labor is also reduced. Finally, by
tying the tool-control function into other manufacturing-control
systems, you’re assured the best control of all tool-related
variables. Let’s look at each issue.
Improved accuracy is one of the best reasons to gain more control
of toolsetting. Because toolsetting accuracy directly affects the
amount of scrap produced, consistently accurate toolsetting is a must.
Furthermore, with untended machining, there is no operator to check
tools before they are used, or check parts during the cycle. That’s
why consistency of toolsetting accuracy is critical. As more automation
is introduced into production, errors are far more costly.
Through automation, the exact information about each tool can be
made available to the toolroom operator. A computer can generate the
tool layout, indicating every dimension and shape.
Then, two different toolsetting approaches can be used to ensure
accurate tool positioning. First, the operator can set the tool exactly
as indicated by the layout, critically positioning the tool at the
specified zero points and checking its geometry in the process.
An alternate approach can be quicker, but requires a more
integrated, DNC-type network. By measuring the tool’s deviation from the specified zero point, then entering this data into the
computer, the system can feed tool offsets directly to a CNC machine.
It actually eliminates the toolsetting function, replacing it with tool
offsetting via the machine control.
As a result, this approach limits tool accuracy to the accuracy of
the machine’s offset system (control, encoders, slides, and ball
screws), but it completely eliminates the need for manual tool
presetting. It’s ideal for turning applications where the tool is
stationary, but less effective for rotating-tool setups.
If there’s anything predictable about workpiece tolerances,
it’s that they always get tighter. A good tool-control system
should be able to accommodate future tolerance requirements as well as
Labor savings are the second important area where advanced toolroom
practices pay off. Toolsetting remains one of the most labor-intensive
operations in a modern metalworking system. Accordingly, it stands to
gain the most from advances in automation. Toolroom automation can
improve worker output and reduce training requirements.
First of all, the labor involved in toolsetting and control is
expanding with the increasing popularity of short runs. Here, tools
must be set up or verified more often. Even if only a few parts are
run, the tooling must be retrieved from inventory, gaged, delivered to
the machine, and returned to inventory.
As a result, it’s possible that more time is spent handling
and setting tools than running parts. The flexibility and time saving
gained through an investment in CNC equipment could be completely
negated by obsolete manual tool-control practices.
The time savings offered by an automated toolroom can really add
up, too. For example, if you have one full-time tooling operator
working at capacity, an automated tool-management system can eliminate
the need for a second person as you get busier. And, because the
toolroom operator can be prompted by the tool-control computer, less
specialized training is required.
Less experienced operators can follow the instructions on the
screen, and those with more experience can use the computer’s
prompting as a reminder. In both cases, tool-setting personnel are more
productive with computer-assisted toolsetting systems because all
necessary information is at their fingertips.
Management and manufacturing information control can both be
favorably affected by automated tool-control practices. From a
manufacturing standpoint, the tool computer helps guarantee the most
up-to-the-minute tool specifications without the need to revise layout
drawings. It can help monitor tool usage, compare tool life, and manage
Through a central computer, you can track tool usage and forecast
when you will need to have certain tools delivered. When inventories
drop below a specified quantity, an order flag can be raised. This
helps minimize tool inventories, yet assures timely replacement of spent
When comparing tool life, statistical analysis can eliminate the
variation associated with irregular tool wear. The analysis shows
underlying tendencies that more accurately reflect typical tool-wear
characteristics. As a result, you can evaluate the cost effectiveness
of different cutting-tool options and make better selection decisions.
From the product-design side of things, computer-aided toolsetting
also can improve responsiveness of manufacturing to part-design changes.
Through an integrated CAD/CAM system, every design change can be
immediately reflected in tool changes. Whether new tools or different
tool settings are required, an automated tool-control system can respond
For shops of any size
The concept of toolroom automation works on nearly any scale,
whether you’ve got three NC machines or 300. And benefits begin
In big shops, centralized tool control reduces inventory, labor,
and cost of engineering changes. If computers are already used, a
computerized tool-control system can tie directly into them, painlessly.
Further, the toolsetting volume of a large shop can mean fast payback.
For shops with as few as three NC machines, the same holds true.
More small shops are using computerized programming systems that make
toolroom automation a natural.
Many computer-aided programming systems generate tool layout and
dimension drawings electronically. Transferring this information to the
toolroom computer eliminates drawings and endless drawing revisions.
One person can handle far more of the overall manufacturing-management
Such systems also can accommodate shop expansion. A modular system
like Royal’s Variset gaging system lets you add capabilities as
Basically, there are four areas where automation can help the
toolroom: Toolsetting, tool storage, tool handling, and tool
information. The requirements of each are simple.
The toolsetting gage must be accurate, efficient, and impervious to
hazards of the shop environment. An effective gage is the most
essential element of an efficient toolroom.
The gaging system must have resolution greater than the closest
tolerance measured. Specifically, better than 0.0002″ for typical
machining operations. (The better the tool-setting accuracy, the better
the accuracy throughout the shop.)
When comparing noncontact with contact gaging systems, noncontact
systems generally will result in better accuracy over the life of the
gage. They reduce the likelihood of problems caused by wear and
contaminants. Toolsetting gages that rely on mechanical contact can
require more frequent mastering and adjustment.
Whatever feedback system is used (glass scales, optical encoders,
magnetic encodors, etc), it should be sealed against chips, oil, and
contamination. Ideally, the entire gage should be protected from the
Some gages allow automatic positioning to the recommended tool zero
point via servomotors. The computer-stored dimensions are relayed to
the gage, and it automatically moves to those coordinates. These
systems are efficient because the operator doesn’t have to manually
position the gage. Over the years, they will pay for themselves many
times over in time savings.
Storage, transfer, and control
Effective tool storage is another important part of an automated
toolroom. Tool-storage systems must meet the same requirements as any
storage system: The tools must be protected, organized so you can find
them, and accessible to appropriate personnel. A variety of
tool-storage systems meet these requirements with capabilities ranging
from simple drawers and cabinets to fully computerized and automated
storage and retrieval systems.
Tool transfer is fairly easily automated with existing technology.
Tools must be transferred between the gage, storage system, machine
tool, and the repair and sharpening area.
The most basic tool-transfer system uses tool-handling modules that
hold and organize several related tools.
These same modules can simplify storage. With tools in place,
modules can be transferred from storage to machine, either by hand, push
cart, conveyor, or automatic guided vehicle. The more automation used
in tool transfer, the better control you’ll have over tools, and
the lower labor requirements will be.
Tool-control systems are extremely important. Increased degrees of
automation require more and more sophisticated control systems.
Information and control needs will vary dramatically, based on your own
shop situation and requirements. For example, various printers and
plotters can produce valuable management reports or tool-layout
drawings, but they add to the overall cost of the system. Whatever
criteria are used to evaluate the toolroom control package, allow for
Control communication capabilities are also important to allow the
toolroom control system to interact with other control systems and
computers. By linking to a host computer, CNCs, material-handling PCs,
and plant-floor feedback devices, an automated toolroom has the
potential to become an integrated part of an entire manufacturing
The concept of toolroom automation is fairly new, but the skills
and equipment required to implement it are available. The costs are
insignificant in light of the returns. Even a partially automated
toolroom can pay for itself through improved control, reduced scrap, and
more effective use of existing personnel and tool inventories. For
information on automated toolsetting equipment and systems, circle E66.