Does your shop need CAD/CAM?Answering 17 simple questions will help determine whether you can justify CADICAM for your machine shop.
in full computer-aided design/computer-aided manufacturing.
Integration of design and manufacturing into a system under direct control of digital computers. isn't just for large manufacturers anymore. With the growing influence of micro-based computers in small and midsized shops, simple CAD/CAM is now affordable to any shop that does CNC (Computerized Numerical Control) See numerical control.
CNC - Collaborative Networked Communication machining.
For example, a simple off-line programming package such as Anilam's Microcam can be purchased for under $1000. Although lacking some features of more complex software, this inexpensive package can construct part geometry; calculate arcs, angles, and tangency points; display finished tool paths; create G-coded output for various CNC controls; and download completed, coded tool paths directly to the machines.
Before even beginning to evaluate a CAD/CAM system, first take the time to evaluate your own company's needs. Many manufacturers and job shops have made the mistake of buying elaborate systems that looked good on paper, but were difficult to implement into actual operation.
Determine who is going to use the system. If you want a system primarily for the machine shop, the software must be machinist-oriented and easy to learn. It also must be easy to interface with every piece of CNC equipment on the shop floor.
On the other hand, be careful to not lock yourself into a dead-end system. Some menu-driven programs are great for beginners, but become cumbersome cum·ber·some
1. Difficult to handle because of weight or bulk. See Synonyms at heavy.
2. Troublesome or onerous.
cum after a basic level of competency COMPETENCY, evidence. The legal fitness or ability of a witness to be heard on the trial of a cause. This term is also applied to written or other evidence which may be legally given on such trial, as, depositions, letters, account-books, and the like.
2. is achieved. Other software programs are little more than dressed-up math packages that cannot easily interface with CNC machinery or perform even simple CAD-to-CAM conversions.
Make sure the software package and supplier offer an upward path for upgrades and expansion, and that the package is highly machinist-oriented.
Once a few basic guidelines guidelines,
n.pl a set of standards, criteria, or specifications to be used or followed in the performance of certain tasks. have been established, you can begin a more extensive, needs-oriented analysis. The following 17 questions will help you get started in evaluating whether or not CAD/CAM can be justified for your shop.
1. Do you machine arcs and angles?
Any time you machine arcs and angles, off-line programming is a tremendous asset. Without it, all line-segment and arc-segment lengths must be found, intersections and tangency points determined, and trig calculations repeatedly performed. Even with the simplest CAM system, however, no trig calculations are ever required. The operator simply defines a series of lines, points, and circles, and enters his tool path. The computer then calculates all line-segment and arc-segment lengths, displays the compensated tool path, and prepares the program for downloading directly to a machine.
2. Do you produce irregularly shaped cavities? In addition to featuring canned cycles for rectangular rec·tan·gu·lar
1. Having the shape of a rectangle.
2. Having one or more right angles.
3. Designating a geometric coordinate system with mutually perpendicular axes. and circular pocket-milling, CAM software also offers irregular pocket clearing. The profile of the pocket is defined, and a simple POCKET command is entered. The computer can either rough out the pocket in a zig-zag pattern to optimize optimize - optimisation the path, or a contour contour or contour line, line on a topographic map connecting points of equal elevation above or below mean sea level. It is thus a kind of isopleth, or line of equal quantity. cycle can be specified. The latter routine will optimize surface finish and reduce benching and polishing time.
Irregular pockets of virtually any configuration, including pockets with islands, can be easily defined and machined, and no trig is needed.
To ensure top accuracy during verification of the finished tool path, some CAM systems also have look-ahead cutter cutter, small, one-masted sailing vessel, with a rig similar to that of a sloop except that it usually has a sliding bowsprit and a topmast. From 1800 to 1830 cutters were in service between England and France. compensation. This feature in a CAM system is vastly superior to even the most expensive CNC controls, both in accuracy (to 10 or more decimal places decimal place
The position of a digit to the right of a decimal point, usually identified by successive ascending ordinal numbers with the digit immediately to the right of the decimal point being first: ) and in sophistication so·phis·ti·cate
v. so·phis·ti·cat·ed, so·phis·ti·cat·ing, so·phis·ti·cates
1. To cause to become less natural, especially to make less naive and more worldly.
For instance, if a particular tool cannot fit in a section of a defined cavity cavity /cav·i·ty/ (kav´i-te)
1. a hollow place or space, or a potential space, within the body or one of its organs.
2. in dentistry, the lesion produced by caries. , the computer will override An arrangement whereby commissions are made by sales managers based upon the sales made by their subordinate sales representatives. A term found in an agreement between a real estate agent and a property owner whereby the agent keeps the right to receive a commission for the sale of the command and flag the operator. Corrections can be made before the first cut is taken, and production of scrap is virtually eliminated. 3. Do you ever use tracing attachments or pantograph Pantograph
A four-bar parallel linkage, with no links fixed, used as a copying device for generating geometrically similar figures, larger or smaller in size, within the limits of the mechanism. machines?
Some common CAM systems have curve-fitting, a feature used to produce undefined shapes. For example, if a machinist is working from an undefined print or mylar transparency, a series of points can be entered, either through a math formula or digitizing "Digitizer" redirects here. For the computer device, see Digitizing tablet. For the digitizer in Tablet PC's, see Tablet PC.
Digitizing or digitization pad. The computer will then generate a smooth curve between the points. Virtually any shape of unknown dimensions can be produced in this way. As a result, the need for tracing attachments or pantographs is greatly reduced.
Some CAM suppliers also offer a 3-D digitizing option. A probe is set up in the CNC machine's spindle spindle: see spinning.
A rotating shaft in a disk drive. In a fixed disk, the platters are attached to the spindle. In a removable disk, the spindle remains in the drive. Laptops use spindle designations to indicate the number of built-in drives. , and a digitizing window is specified. As the probe touches the model or prototype, 3-D points are generated and uploaded to the off-line computer. There, all CAM features are at the operator's fingertips "Fingertips" is a 1963 number-one hit single recorded live by "Little" Stevie Wonder for Motown's Tamla label. Wonder's first hit single, "Fingertips" was the first live, non-studio recording to reach number-one on the Billboard Pop Singles chart in the United States. .
The part image can be scaled up or down, eliminating the need for shrink-models and duplicating tools. The image can be translated, rotated rotated
turned around; pivoted.
see rotated tibia. , or modified in any configuration.
Moreover, cutter compensation can be added, and the finished tool path can be postprocessed for any CNC control in your shop. 4. Do you ever produce families of parts?
If you machine parts that have similar shapes but different sizes or proportions, you'll find CAM programming ideal for modifying previously written programs. Once a shape has been defined, it can be manipulated in a number of ways. For example, it can be moved in X, Y, or Z, a technique perfect for creating multiple-cavity molds. Moreover, a shape can be rotated by any angle, or scaled up or down in precise proportions. Multiple zero reference points can be set up for multiple fixturing. In a word, CAM programming adds great power and flexibility to any CNC machine tool. 5. Do you have multiple CNC machines?
If you operate more than one CNC machine tool, off-line programming can become a big time-saver. CAM allows you to use only one programming language to program all your CNC controls.
With a good universal postprocessor (provided at no extra cost in some packages), the tool path shown on the screen is automatically converted into the NC-coded data necessary to run machines with different CNC controls. You simply enter the file name of a particular CNC machine, run the program through the postprocessor, and download the completed, coded program directly to the machine.
Scheduling also is improved dramatically.
Since one CAM terminal can serve several different machines, scheduling changes often can be made at a moment's notice. If, for example, a CNC machine is tied up on a production job, a portion of the program can be redirected to another machine, even if it uses a different make of control and programming format. CAM keeps your CNC spindles turning for increased productivity and profits. 6. Do you ever do production (100 to 1000 pieces) machining?
If you perform relatively long production runs, programming time seems insignificant when compared to actual cycle-time needed per part. If spending an extra hour of programming time results in saving 2 minutes a part in a 500-part run, however, more than 16 hours of expensive CNC machining will be saved in that run.
CAM is perfect for long-run production. During machining of a cavity, for instance, the most efficient machining path can be chosen quickly. To verify your choice, some software will even calculate and display the cycle time for any given cutting tool, before the first cut is taken. Editing time is minimized, but efficiency of your CNC machine is maximized.
7. Do you produce batch (12 to 100 pieces) production runs?
If you usually produce part-runs of 12 to 100 pieces, CAM can give you the best of two worlds. When you're machining long runs, the cycle-time saving benefits of CAM will save hours of machining inefficiency. During machining of short runs, CAM's savings in programming time will make your quotes more competitive.
8. Do you perform short-run (1 to 12 pieces) production? If you produce relatively short runs of, say, 12 pieces or fewer, offline programming can save a great amount of time and money. For example, if a typical job takes 4.5 hours to program manually, but only 1.2 hours to set up and run, then 82% of total production time is spent on programming.
A simple CAM system cuts programming time in half for even the most common profiles, and time-savings of 90% to 95% are often reported on complex work. Projects that would have been impractical im·prac·ti·cal
1. Unwise to implement or maintain in practice: Refloating the sunken ship proved impractical because of the great expense.
2. to set up and program manually become competitive when off-line programming is used.
9. Do you still produce one-of-a-kind work manually? Because of time needed to write CNC programs manually, some operators prefer to produce one-of-akind work conventionally, instead of using CNC. With a CAM system installed, however, it is almost always more practical to use a CNC machine to produce a part. That's because programming time is generally reduced by 50% to 95%. If you can keep even one CNC machine busy an extra six hours a week, that machine will produce at least an additional $10,000 in profit during the first year.
10. Do you enter your programs into your CNC controls manually? Even if you have only one CNC machine tool on the floor, downloading programs from an off-line programmer (1) A hardware device used to customize a programmable logic chip such as a PAL, GAL, EPROM, etc. See PROM programmer.
(2) A person who designs the logic for and writes the lines of codes of a computer program. has its advantages. Some programs may consist of many lines of information, and could take your operator hours to enter and prove-out manually. Furthermore, errors sometimes occur while the program is being entered manually. This causes the waste of even more time for proving and editing programs. Meanwhile, the CNC machine is not producing parts or making money. With off-line programming in use, though, all programming and editing can be performed away from the machine. Also, the completed tool path can be verified before the first cut is taken. Once the operator is satisfied with his program, he postprocesses it and downloads it to the machine. Then all he need do is set his tool at zero and press the START button. A recent survey estimates that with an off-line computer for part-programming, the average shop can save at least 240 hours a year in program entry time. At a shop rate of $30 an hour, that's an annual savings of $7200 per CNC machine.
11. Do you have a drafting department? if you design your own parts or fixtures, you ought to seriously consider adding a design and drafting extension to your CAM system. CAD saves a lot of time in design, dimensioning, and modification of part drawings. Moreover, once a print is finished, 90% of your CNC programming is already completed. CAD-to-CAM conversion automatically transfers line drawings on the screen into actual geometry needed to machine a part. With only a few simple modifications, tooling and machining information can be added. Complete CNC programs can then be downloaded to your CNC machine tools.
12. Do you have a Quality Control (QC) department?
CAD/CAM streamlines your QC procedures from beginning to end. Since many common CAM systems are accurate to 10 decimal places, critical dimensions on a blueprint blueprint, white-on-blue photographic print, commonly of a working drawing used during building or manufacturing. The plan is first drawn to scale on a special paper or tracing cloth through which light can penetrate. can be found and verified before the first cut is taken. In many cases, discrepancies in the customer's blueprint specs (SPECificationS) The details of the components built into a device. See specification. can be found quickly and corrected. This precludes long delays and rework re·work
tr.v. re·worked, re·work·ing, re·works
1. To work over again; revise.
2. To subject to a repeated or new process.
n. costs. Once a blueprint is programmed and verified, a listing of X-Y-Z coordinates can be printed out in seconds. Since these dimensions are exactly the same as those being outputted to the CNC machine tool, QC is once again made more efficient.
Easy comparisons can be made between print, program, and part, without human error playing a significant role. Any changes in tooling, feed-rates, or surface finish can be made quickly.
13. Do you have full-time CNC programmers This is a list of programmers notable for their contributions to software, either as original author or architect, or for later additions.
See also: Game programmer, List of computer scientists
If you employ one or more machinists dedicated to writing CNC programs, off-line programming is definitely for you. Anyone familiar with CNC programming knows that the most difficult part of writing a program is defining part geometry and determining the most efficient tool path. CAM programming makes such work easy, even in the hands of a relatively inexperienced in·ex·pe·ri·ence
1. Lack of experience.
2. Lack of the knowledge gained from experience.
in programmer. On the other hand, when CAM is used by a skilled programmer, its power and flexibility are practically unlimited. Custom canned cycles can be written, and loops and variables can be employed. Even sophisticated logic commands are readily available to the operator.
14. Have leave-time or employee turnover ever presented problems to you?
When evaluating a CAM package, make sure it is designed for machinists, not for computer programmers. That way, any machinist with a solid machine-tool background and good planning habits will quickly master its simple programming format. Training and startup time will be kept to a minimum. Also, make sure the package has a flexible postprocessor, so all your programming can be done through one keyboard. Instead of trying to make every machinist memorize mem·o·rize
tr.v. mem·o·rized, mem·o·riz·ing, mem·o·riz·es
1. To commit to memory; learn by heart.
2. Computer Science To store in memory: many different CNC G-coded languages, all your machinists can learn just one language. If a programmer takes leave, any other programmer can easily fill in, regardless of which CNC control units are involved. Downtime The time during which a computer is not functioning due to hardware, operating system or application program failure. is thereby kept to a minimum. 15. How do you store your NC programs?
If you currently store part programs on paper tape or microcassettes, or if you require hardcopy backups of your programs, then off-line programming systems give you added benefits. For one thing, all programs are stored on hard disks for easy manipulation and data retrieval.
This is an advantage because a 10MB hard disk has the ability to store 10 million characters of information. This is equivalent to about 160,000 feet of paper tape. One 10MB disk holds literally thousands of programs and subprograms, each retrievable in seconds.
Furthermore, specialized spe·cial·ize
v. spe·cial·ized, spe·cial·iz·ing, spe·cial·iz·es
1. To pursue a special activity, occupation, or field of study.
2. cycles such as routines for scribing scribe
1. A public clerk or secretary, especially in ancient times.
2. A professional copyist of manuscripts and documents.
3. A writer or journalist.
4. See scriber.
v. alphabet alphabet [Gr. alpha-beta, like Eng. ABC], system of writing, theoretically having a one-for-one relation between character (or letter) and phoneme (see phonetics). Few alphabets have achieved the ideal exactness. characters can be called from the disk at random, and added to any program you're running. As your part library grows, your programming power increases as well. Another benefit lies in the fact that hard-disk and floppy-disk storage are economical. A 360K floppy sells for about $3, replacing at least $300worth of microcassette tapes. A 10MB hard disk can replace as much as $10,000-worth of tapes. 16. Do any of your customers use
CAD or CAM?
If "yes," off-line programming may give you extra advantages. Most CAM programs convert DXF files (Document EXchange Format file) An AutoCAD 2D and 3D graphics file format. ASCII based, many CAD systems import and export the DXF format for graphics interchange. or are compatible with IGES (Initial Graphics Exchange Specification) An ANSI file format that is system independent and also intended for human interpretation. Evolving out of the U.S. . This allows the programs to interface with nearly all popular CAD software packages on the market. By using an inexpensive telephone modem, you can transfer your customers' part drawings, with all C data, to your CAM workstation, and plot them out for easy reference. The entire program can then be converted automatically to part geometry, a tool path added, and a finished program downloaded directly to a machine.
17. Have you ever thought about upgrading or expanding your
CAM systems add programming features and powerful canned cycles to almost any CNC, regardless of price or complexity. Many analysts therefore see off-line programming as the way of the future for even the smallest machine shops. In fact, some experts predict that the CNC controls of the future will be little more than black boxes supported by off-line computers. These will be tailored to the user's special needs. Software updates and increased specialization A career option pursued by some attorneys that entails the acquisition of detailed knowledge of, and proficiency in, a particular area of law.
As the law in the United States becomes increasingly complex and covers a greater number of subjects, more and more attorneys are will become much more cost-effective, and every control in the shop will be able to operate at the same level of sophistication.
When all the cost-saving benefits of a simple, off-line programming system are considered, a small investment in CAD/CAM may become an excellent way to modernize mod·ern·ize
v. mo·dern·ized, mo·dern·iz·ing, mo·dern·iz·es
To make modern in appearance, style, or character; update.
To accept or adopt modern ways, ideas, or style. your machine shop and improve the efficiency of your CNCS CNCS Corporation for National and Community Service
CNCS Cryptonet Control Station
CNCS Cold Neutron Chopper Spectrometer (Oak Ridge National Lab project)
CNCS Centralized Network Control Station .