Use Your CNC Wisely

All CNC users share at least one common goal. They all want to use their CNC machine tools more effectively. To reach this goal, companies work to improve quality, extend tool life, and make better use of CNC people. Improvements to CNC utilization can come in many forms. Reducing setup time may be important to companies that work with small lot sizes. Companies with large lot sizes may want to reduce cycle times. Reducing programming time is important to companies seeing little or no repeat business. There are many reasons why these companies work to improve their CNC utilization.

Since companies have different needs, one company’s strategy for improving CNC utilization may be completely different from another’s strategy. This can lead to confusion and controversy among CNC users. Even people in the same CNC environment may disagree over the most effective use of the CNC machine tool. Users become even more bewildered when they consider the claims of the machine tool, control, and accessory suppliers, who tend to make their CNC-related products sound right for everyone. The suppliers’ vagueness can easily lead to a misapplication of the products and detract from a shop’s ability to optimize its CNC utilization for its specific needs.

If you are seeking ways to improve your shop’s CNC utilization, about the only way to avoid conflicts is to thoroughly understand your company’s priorities, corporate identity, and corporate goals. This article will get you thinking about your company’s optimal CNC utilization—and how far you may be from achieving it. To develop an optimization strategy that is right for your company, you and everyone else in your CNC environment will need a thorough understanding of your company’s priorities. While much of what is presented here is relatively easy to understand, you may be dismayed by the number of misconceptions and misunderstandings that currently exist among people in your CNC environment.

Understand Your Company
The most basic factor to consider is your company type. There are really only four types of companies using CNC equipment: product-producing (production) companies, workpiece-producing companies (contract shops), tooling-producing companies, and prototype-producing companies. The most complex CNC environments tend to be in production companies because of the diversity of machining operations involved. Some companies may have difficulty categorizing themselves because the work within their CNC environments involves more than one type of production. For instance, a production company may have a toolroom and an R&D department that produces prototypes. A contract shop that primarily produces workpieces for other companies may additionally have a product line of its own.

Your company type is the most important factor contributing to your company profile, and it sets the trend for how other factors impact the CNC environment. But there are many other company factors that you must consider if you are to make wise decisions concerning your CNC environment, including:

• CNC personnel utilization;
• Company location (rural versus urban);
• Your CNC staff’s competency level;
• Machine types owned;
• Age of equipment;
• Tooling utilization (cutting and workholding);
• Consistency among machines/ controls;
• Lot sizes;
• Percentage of repeat business;
• Similarity among machined workpieces;
• Materials machined;
• Accessibility/cooperation of product designers;
• Emphasis on just-in-time (JIT);
• Tolerances held;
• Emphasis on quality control.

In all but the smallest companies, organizing and understanding the CNC environment is no easy task. The factors just mentioned may represent conflicting needs within your company, and these needs must be prioritized. You may have to sort through factors that can be combined in almost limitless ways. To complicate matters further, many companies also must recognize that different departments have different needs. One area of the company, for example, may have 100% repeat business, rather large lot sizes, and similar workpieces. Another may never see the same job twice, work with lot sizes of one or two workpieces, and find there is absolutely no similarity among machined parts. Applying the same CNC-optimization methods to both departments would waste at least one department’s time and resources.

Feasibility further complicates the decision-making process in your CNC environment. Anything may be possible, but given limited resources, not everything is feasible. Use the repetitiveness of the task to help determine how feasible it will be to improve it. Generally speaking, the more times any task is repeated, the more feasible it is to improve the task, and the easier it will be to justify what you intend to do.

However, even measures that won’t produce extensive improvements or may not apply directly to the areas of your concern may be feasible simply because they are inexpensive. A company that runs small lots, for example, may not be overly worried about program-execution time, but it should still implement any program-formatting improvements that speed execution since they cost nothing to employ.

Each shop using CNC machines will find its own way to satisfy the conflicting needs within its operation. While these specific improvement efforts vary from one CNC user to the next, most successful efforts tend to follow general concepts for continuous improvement that remain amazingly fixed. These concepts, as outlined below, can form a foundation on which your CNC-utilization improvement program can be built. As you review these concepts, please keep in mind that the specific examples given are included for the sole purpose of illustrating the points being made.

Inspire Aggressive Awareness
Any continuous-improvement program requires aggressive awareness, which is that attribute within us that causes us to search out potential improvements. Aggressive awareness begins with the realization and acceptance that there is room for improvement in every area of your CNC environment. As human beings, we must fight our natural tendency to leave well enough alone. The saying may advise you, “If it ain’t broke, don’t fix it,” but just because your CNC machines seem to be running smoothly (they are not broken), they may not be running at optimal levels. They may not need fixing, but they can certainly use some improvements.

Of course, you cannot begin to apply a technique unless you know (or suspect) it is possible to do so. How do you and your people gain this knowledge? Education is the key.

Your machine tool builders and control manufacturers publish usage manuals to help you understand their products. While these manuals are obvious teaching tools, too many CNC users treat them solely as reference material, referring to them only when faced with a specific problem. In addition to supplying reference information, your machine tool usage manuals contain a great deal of information about usage alternatives. Admittedly, some manuals are difficult to read and absorb (especially those translated from another language), but to ignore them as a source of ideas for improving your CNC utilization can be an expensive mistake.

Confirm your understanding of all M-codes. A review of your machine tool’s manual may uncover important M-codes that, all too often, get ignored. While most of us know the codes for common functions, even experienced CNC users may be ignorant of the codes for unique or uncommon functions. Example: One company’s programmers wanted to reduce program-execution time. They noticed that whenever a spindle orientation was programmed (M19) to occur during their machining center’s return to the tool-change position, this machine would still wait until the motion was completed before performing the spindle orientation. Upon further study, they found that two other M-codes control whether a motion must be completed before M-codes begin activation. By including a simple M-code in the program, the spindle orientation now occurs during the tool’s motion to the tool-change position, saving precious cycle time.

Most machine tool manuals include a lists of M-codes and the functions they control. As you study these lists, you may discover some obscure functions that are not very well described in the manuals. You may have to contact your machine tool builder to learn more about how these M-codes function. The effort could pay off in an improvement you would not have considered otherwise.

Familiarize yourself with all of your machines’ standard features. By carefully studying your machine tools’ manuals, you will learn about all their standard features. If all you know about your machines is what you learned during your initial training (commonly supplied by the machine tools’ supplier), you’ll likely find many unfamiliar features and functions in your machine tool manuals. These additional features may allow you to perform operations that you thought were impossible. Example: One company wanted to reduce setup time by eliminating tasks related to assigning program zero during setup. Since the operators made qualified setups—locating fixtures from keyslots on their machining center—the program-zero location for each setup remained the same every time the setup was made. By studying the programming manual, the operators learned that they could program the program-zero setting with fixture offsets. This not only eliminated the program-zero measurements, it eliminated the need to enter them in the program as well.

You should familiarize yourself with all of your machines’ features, even if you have little need of some of them at present. If you know how these features operate and what functions they perform, you’ll be able to recognize applications for them when the need arises. Again, your review will probably uncover features that are not well explained (the builders’ manuals often neglect to show you why certain features are important). You may have to contact the machine-tool builder directly to get the full details.

Learn about available options. Your machine manuals also include documentation on available options. Even though you may not have access to these features currently, by studying the manual, you will know that they are available and what they can do should you need such a feature in the future. Example: One user was struggling with a turning center that had, in addition to x- and z-axes, a rotary c-axis within the spindle that allowed the user to perform secondary operations not commonly considered turning operations (milling, drilling, slotting, etc.). This company found it extremely difficult to program the machine to mill flats or contours on the face of the workpieces. An elaborate CAM system had to be used to generate a lengthy CNC program for the machining of the face contours and flats. Upon further study, the company learned that an optional feature called polar-coordinate interpolation makes the programming of face contours and flats as easy as any other motion. Based upon the amount of face work this shop performed, its programmers easily justified the purchase of this option.

Learn about power curves. Your machine tools’ manuals also can inform you about your machines’ horsepower curves, a topic many users ignore. Your machine may reach full horsepower at specific speed ranges. Only by knowing where these peaks occur can you program the machine efficiently and avoid speed changes that force the machine to shift from one range to another. Example: The managers at one shop noticed several undesirable pauses when the shops’ machining center changed tools. Upon further study, they found that their machining center had two spindle ranges (the programmer didn’t even know this) and that the machine automatically selected the spindle range based upon the programmed spindle speed (S-word). If the speed required the high range, the machine automatically made the range change. The managers found that there was absolutely no consideration being given to range changing. By grouping together all tool operations that required the same range, the programmer was able to reduce execution time.

Learn the functions of all buttons and switches. Can your CNC people readily identify every button and switch (including all display soft keys) on your machines’ control panels? If they cannot, they may be unaware of some helpful function that is available. Example: One programmer was constantly forced to make mass changes to CNC programs at the machine. To make these modifications, he would always go back to the PC-based text editor. Upon further study of the control manual, he found that the control had “cut-and-paste” ability. And even better, he found that this function worked much the same way as the offline text editor!

Search for features that apply to your specific applications. Machine tool suppliers tend to teach you safe, easy, and convenient techniques for using your CNC machines. But the easiest way to handle a problem is seldom the most efficient. Only by studying everything can you determine the features that will be especially beneficial to your company. When you discover a feature that makes little sense, ask yourself “What could this feature do for me?” Example: One programmer works for a company that machines 300 workpieces in a very close family. While studying the programming manual, this programmer learned that parametric programming could handle all parts in the family with one CNC program, eliminating the need to maintain 300 hard-and-fixed CNC programs.

Explore Low-Cost Resources
Being aggressively aware extends beyond understanding what is included in your machine tool manuals. You will also want to explore other sources for techniques to improve your CNC utilization. Some of these resources are free (or close to it), yet they go largely overlooked.

Read trade journals. Many of the trade journals related to manufacturing place a strong emphasis on CNC technology. Several people in your company probably receive these publications already. For your shop to use journals effectively, however, you must confirm that they are they being read by the people who are in the best position to use the information. Since these journals often contain Articles about the most recent developments in CNC technology, why not make them required reading? Example: One CNC user was able to create a complete distributive-numerical-control (DNC) system using information supplied in a trade-journal article.

Visit your local library. If you’ve never visited the manufacturing section of your local library, you might be quite surprised at the number and quality of books related to manufacturing. Note that most libraries have excellent computer-based indexing capabilities, making it possible to research almost any topic. Example: One machining-center programmer was able to find every book and article written about thread milling when he asked the reference librarian to perform a computer search on the term.

Log on to the Internet. More and more CNC resources are becoming available on the Internet. There is even a news group (alt.machine.cnc) that provides a forum for CNC users. Example: Would you like another user’s opinion of a CNC accessory you intend to purchase? Pose the question to the news group mentioned above. Someone in the group probably has experience with the accessory and will be willing to give their frank opinion.

Talk to accessory-device salespeople. Salespeople can tell you about the benefits of CNC accessories that can help improve CNC utilization. But you must be critical when judging the quality of their information, since they have a vested interest. Salespeople you might talk to include those working for CAM-system providers, distributive- and direct-numerical-control system providers, probe manufacturers, bar-feed manufacturers, pallet-changer manufacturers, and tooling and fixturing suppliers.

Attend seminars and clinics. Organizations such as the Society of Manufacturing Engineers (SME) sponsor a number of seminars and clinics aimed at keeping you abreast of the latest developments in manufacturing. Among the topics covered are setup- and cycle-time reduction, high-speed machining, rapid prototyping, and parametric programming. While these sessions are kept somewhat generic to make them relevant to a wide variety of CNC users, they do offer an excellent way to keep up with changes in this field.

View training videos. A number of suppliers offer training on videotape. These video courses frequently offer the same kind of material the suppliers present in seminars and clinics.

Attend trade shows. Machine tool builders are always eager to show off their latest developments at trade shows. For personal help, they make specialists available that can answer your questions.

Beware of Convenience Features
Before machine tool builders began incorporating computers into NC machines, the machines were cumbersome to operate. In the years since, machine builders and control manufacturers have worked very hard to make their products easier to use. We call these features “convenience features.” Truly, current models of CNC machine tools, despite the fact that they are much more sophisticated than their predecessors, are much easier to program, set up, and operate.

However, you must be aware that to incorporate nearly any convenience feature, you will have to pay some kind of penalty. In some cases, the convenience will fill a company’s needs, and the benefits will outweigh the penalty. In other cases, the penalty will be very severe, and alternatives must be found.

Tool-length compensation. One classic example of a convenience that carries a penalty is the tool-length compensation feature found on machining centers. While this is an extremely helpful feature, and we recommend that every CNC user should employ it, you must be careful to minimize the setup-time-related penalty it may be forcing you to pay. If, for example, tool-length compensation forces your setup people to measure tool lengths right on the machining center, the machining center is functioning as nothing more than a very expensive height gage during setup. There are situations in which tool-length compensation makes sense even if there is a severe setup-time-related penalty involved. Perhaps lot sizes are small, cycle times are short, and/or the only person to perform all the CNC tasks is the CNC operator. In this case, tool lengths may have to be measured online during setup. In most cases, however, it is possible to measure tool lengths for the next setup offline while using tool-length compensation. These measurements can be performed even while the machine is in the current production run.

Probing systems. Probing systems can be convenient, but you should explore all other possibilities before deciding to use one. The penalty for systems that aid your people during setup, such as spindle probes, tool-length-measuring probes, and turning-center tool-touch-off probes, will be longer setup times. The penalty for probing routines that must be executed in every cycle, such as spindle probes, is longer cycle times. While there are many excellent applications for probing systems, be sure you are applying them wisely.

Parametric programming. While this feature can facilitate your CNC usage in many ways, it does require heavy processing power from the CNC. In some cases, the calculations and logic that parametric programming requires will increase cycle time.

Canned cycles. Like parametric programming, some canned cycles require so much processing that they will cause pauses long enough to increase cycle time during program execution. Additionally, there are many control parameters that affect how your canned cycles behave, and these parameters may have an effect on cycle time as well. In chipbreaking peck drilling, for example, a parameter controls the distance the tool will be retracted from the current hole bottom between pecks. This distance will have a significant influence on the time it will take to drill the hole.

These are just some of the ways convenience features force you to pay some kind of penalty. You will have to examine the features you use, identify the penalty, consider your alternatives, and determine whether the penalty is acceptable based upon your own applications.

Eliminate Bottlenecks and Waste
A CNC machine represents a large investment for a shop. Any time it sits idle, the delay increases the time it will take for the shop to recover its investment. All shops have bottlenecks: workpieces don’t reach assembly at the appropriate time; tooling is not ready for the setup person when a setup is started; the CNC program isn’t finished when the setup is completed; the operator can’t find the program in your distributive-numerical-control system; new programs take too long to verify; the machine sits idle while the first workpiece is being inspected; or replacement tools are not readily available as tools dull during the production run. The list of potential bottlenecks goes on. Here are the steps to take to find and eliminate the bottlenecks in your CNC environment:

1. Identify the bottleneck. Most bottlenecks are easy to detect. Whatever keeps people or departments from completing their tasks in a timely manner is a bottleneck. One of the most common bottlenecks for companies that run small lots is the excessive time it takes to make setups.
2. Evaluate current methods. Once you have identified the bottlenecks, you must carefully examine them so that you can target areas for improvement. A company complaining about lengthy setups, for example, should begin by studying how setups are currently made. Videotaping tasks related to the bottleneck will provide information that can be studied by everyone in the CNC environment.
3. Formulate suggestions for improvement. Once you have gathered the information, invite everyone involved with the problem to suggest and evaluate ways to improve the operation. This can be treated as a brainstorming session, in which all have an opportunity to express their ideas. A company experiencing long setup times, for example, might find through evaluation that the setup person is always searching for the required hand tools and gages. One suggestion that might come out of a brainstorming session about this problem might be to supply each setup person with his own set of tools.
4. Prioritize based upon benefit and feasibility. With a variety of viable solutions to consider, you’ll need to pick the one that best suits your company’s corporate goals. Every potential improvement must be justified, and most of these justifications are cost-based. In the setup-time-reduction example, it would probably be easy to justify additional hand tools and gages based on the money the shop loses while operators search for tools. The time (and, therefore, the money) the shop saves can easily pay for the additional hand tools in a very short period of time.
5. Consider improvements that cannot be justified by cost. Some improvements must be carried out to further the company’s corporate goals and philosophies. If, for example, your company places a high emphasis on JIT, workpieces must reach the next step in the manufacturing process when they are scheduled to arrive. In this example, the cost of eliminating a bottleneck would be weighed against the possibility of missing the shipping deadline rather than the shop rate of the CNC machine causing the bottleneck.
6. Don’t take “no” for an answer. Even with limited resources, there is very little a shop can’t do with its CNC machine tools. Given your new-found aggressive awareness, ingenuity, and determination, you should be able to eliminate any bottleneck.

An evaluation of your shop’s bottlenecks (especially if you have never applied these principles before), will probably reveal many ways that your operations waste time, effort (in duplicated tasks), and money. As you review the videotape of a setup, for example, you may see the setup person look around for a few moments and then disappear. Ten minutes later he comes back (breathing hard) and starts the setup. After two more minutes, he disappears again. This continues throughout the setup. By the end of your review, you find that the setup person is actually at the machine a small percentage of the time.

When you ask the operator about his disappearances, he explains that each time he left the scene he was looking for something. “I had to get hand tools,” he might say, or “I had to get cutting tool components from the tool crib.” It becomes obvious that the setup person (probably through no fault of his own) was not well prepared to make the setup in the first place. You may discover many such examples of waste. It is not uncommon for a company’s employees to be spending a great percentage of their time performing unproductive tasks.

Be Consistent Whenever Feasible
Inconsistencies lead to waste. The most seriously wasteful inconsistencies are those related to your company’s corporate philosophies and goals. Here are a few examples of such waste:

Company location. A company might locate in a rural area to save on labor costs. But such areas may have a very limited manufacturing base. It would be inconsistent for a company to try to save money by locating in a nonmanufacturing area and then be unwilling to train newcomers.

Lot sizes. A company that commonly runs medium to large lot sizes and enjoys plenty of repeat business will have ample time during the production run to prepare programs offline. It would be inconsistent of this company to expect its CNC operators to program every job during setup using the machine’s conversational controls. Just the opposite might be true if the company has no time to program offline because it has several CNC machines running small lot sizes and no repeat business. One programmer would have difficulty keeping up with all the machines if this were the case. A solution more consistent with this company’s type of business would be to use shop-floor programming.

JIT. It would be inconsistent for a company to plan to meet JIT delivery schedules when it is unwilling or unable to invest in adequate CNC accessories to complete jobs efficiently.

Cells vs. stand-alone machines. A company that does not run a number of similar processes would be wasting its resources if it tried to group its processes into cells. The use of stand-alone CNC machines would be more consistent with the type of work the company performs.

First-workpiece inspection. It would be inconsistent for a company with wide-open tolerances to require an inspector to check the first workpiece while the machines remain idle. A more efficient use of manpower would be to let the setup person measure and be accountable for these tolerances.

Dimensioning and tolerancing. Waste can result when design engineers at a company employing many entry-level people dimension and tolerance on blueprints in a way that forces these less-skilled employees to perform calculations.

DNC system. A company with a great deal of repeated short-run business will perform many program transfers. Such a company will find a distributive-numerical-control system that forces its programmers or operators to make transfers at only one location to be more cumbersome than a system that allows operators to transfer programs at their machines.

Fortunately, when it comes to inconsistencies that conflict with your corporate goals and company profile, most lead to serious bottlenecks that can be identified easily. Unfortunately, these inconsistencies can be the most difficult and expensive to eliminate, because they represent fundamental and entrenched methods and procedures.

Inconsistencies may also be introduced as you increase the number of CNC operations you perform or add CNC machines. Though the variety of machine types you work with may make it impossible to use the same methods and procedures throughout, you can minimize confusion in the CNC environment by keeping things as consistent as possible. Here are a few examples:

Machine and control types. It is easier for everyone if the same type of machines and controls are used throughout the shop. Unfortunately, the technologies surrounding CNC are constantly changing, and machine tool suppliers are constantly vying to see who can offer more and better features. You will have to decide if a machine/control combination that is unfamiliar to your people satisfies your company’s needs well enough to make it worth the bother.

Programming methods. Programs created in the same basic format for each machine can be read and understood by everyone in your operation. If you employ more than one programmer, however, each is probably following what he considers the best program format. While each format works, they may differ from one another significantly. Reducing the inconsistencies in these programming formats will prevent confusion among your people.

Operation methods. It is likely that any given CNC machine tool will be run by more than one of your operators. To avoid confusion and the potential for mishap, each operator should handle the machine in the same manner. For example, if operators perform tool maintenance with no regard for the other operators’ maintenance schedules, it’s likely that tools will last a different amount of time for each operator.

Educate Your People
Making your people more proficient at their jobs will be more beneficial to your CNC utilization than any other improvement. A well-trained programmer will prepare safer, more efficient, more workable programs. A well-trained setup person will make better, safer setups more efficiently. A well-trained operator will efficiently run better parts and never cause a crash.

There are five levels of CNC proficiency, though most CNC users must train at only one or two of these levels. Each level demands specific skills and knowledge in addition to the skills and knowledge required by the lower levels. The five levels include:

Level 1-The ability to communicate intelligently. Everyone in the CNC environment, including those who do not work with the CNC machines on a regular basis, should have a working knowledge of CNC. Managers, foremen, design engineers, manufacturing engineers, quality engineers, inspectors, and tool setters should have, at the least, enough understanding of CNC-machine basics to communicate with the people who do use CNC. You probably wouldn’t consider sending most of these people to a machine-tool builder’s CNC course, but they may benefit from a builder’s overview course or a review of the basics that may be found in textbooks or manuals.

Level 2-The ability to operate CNC machines. Operator responsibilities commonly include workpiece loading and unloading, program activation, workpiece measurement, SPC reporting, offset adjustment, and tool maintenance. CNC operators make up the bulk of the people in the CNC environment. A company with five CNC machines might have one or two programmers, two or three setup people, and 15 operators (one for each shift on all five machines). The number of people involved at this level, coupled with the difficulty shops are having locating new hires with CNC-operation experience, makes this level of proficiency the most important to most companies. CNC operators should have a good grasp of basic machining practice (blueprint reading, the use of measuring tools, shop math, etc.).

Level 3-The ability to set up CNC machines. Though many companies expect their CNC operators to make their own setups, a number assign the job of making setups to special people. In addition to all the responsibilities related to CNC-machine operation, a setup person’s duties include making workholding setups, assembling cutting tools, entering measurements and offsets, assigning program zero, loading and saving programs, verifying programs, and running the first workpiece.

Level 4-The ability to program CNC machines. A good programmer should have a firm understanding of all the responsibilities related to operation and setup. In addition, he should be able to develop a sequence of machining operations (a process), plan for cutting tools and fixturing, develop setup and program-running documentation, develop the CNC program, and help verify and run the program should questions arise.

Level 5-The ability to teach CNC. If your company is going to train its own people, you’ll need an instructor. A good instructor is patient and willing to convey information freely, has a firm understanding of the material, and is able to work with a wide variety of people.

Evaluate Your Training Alternatives
CNC training for people at each level of proficiency is available from several sources. You will probably find your machine tool suppliers to be among the most accessible training sources. All machine tool suppliers provide training for the products they sell. However, these courses tend to be quite condensed, and they are designed with the assumption that attendees already have a firm understanding of the machines being discussed. These courses tend to be very good for your CNC programmers/setup people, but most delve too deeply into the subject of CNC operation for entry-level operators.

As an alternative to supplier training, you might find help with training at your local technical schools. With the excellent CNC curriculum most offer, they provide cost-effective training that is useful even for entry-level operators. Many schools will tailor a course to your needs, and some will teach on your premises.

For additional aid, you can seek the help of outside training suppliers. Organizations such as SME provide regular public seminars related to CNC. Seminar schedules can be found in the organizations’ literature, on their Web sites, or in listings in trade publications. Most organizations that sponsor training provide in-plant versions of the seminars as well. Additionally, many training consultants offer custom training to address your specific needs.

If you would rather not schedule training sessions with outside people, you can still offer the benefits of their expertise to your employees by making training videos and computer-based training available. There are many excellent videos and computer programs for teaching CNC basics as well as more advanced topics.

Unfortunately, none of the resources just mentioned will allow the level of fine-tuning your training program may need. You may, for example, wish to combine some basic machining-practice skills with your CNC-operator training. Developing your own in-plant training program will give you the ability to tailor the curriculum to your needs.

Don’t Give Up
Your willingness to stick to your CNC-utilization improvement efforts until you achieve your goals will have a significant influence on your success. All too often, people give up on a good idea at the first sign of trouble. Only your persistence will ensure that the effort you make will yield results. When you are sure an idea will have a desirable impact on your CNC environment, stick with it until you make it happen.

Author’s note: My company, CNC Concepts, Inc., maintains a Web site (http://www.cncci.com) that contains a number of items of interest for CNC users. Along with our product information, there is a CNC help forum, a CNC tips forum, a CNC jobs forum, and interactive Articles about CNC. I encourage you to e-mail me (lynch@cncci.com) with any questions or comments you have about this article or CNC in general.

About the Author
Mike Lynch is president of CNC Concepts, Inc., Cary, IL.