CNC Magazine

volume 9 • issue 33

FEATURESFEA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

GOB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

BOTTLES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

SURFCAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

CONTROL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

EDUCATIONPOLYTECHNIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

CYCLE TIME50K . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

EXPANSION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

NEWTECH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

THE ANSWER MANTIPS/TRICKS/ANSWERS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

TABL

E OF

VOLUME 9 ISSUE 33

CONTENTS

CNC MACHINING is published by Haas Automation, Inc., 2800 Sturgis Road, Oxnard, CA 93030, 805-278-1800, Fax 805-988-6918. Postmaster: Return invalid

addresses to Haas Automation, 2800 Sturgis Road, Oxnard, CA 93030-8933 postage guaranteed. CNC Machining is distributed free of charge by Haas

Automation, Inc., and its authorized distributors. CNC Machining accepts no advertising or reimbursement for this magazine. All contents of CNC Machining

are copyright 2005 and may not be reproduced without written permission from Haas Automation, Inc. CNC Machining is distributed through a worldwide

network of Haas Automation distributors, and by individual subscription request. Contact Haas Automation headquarters via mail or fax to be added to the

subscription list. © Haas Automation, Inc. & CNC Machining Magazine names. Designed and printed in the U.S.A. CPC # 40675626. www.HaasCNC.com.

Haas Automation Europe, ++32-2-522-9905 | United Kingdom, ++44-1603-760 539 | Haas Automation Asia, ++86 21 5046 2202

In This IssueWho in the world came up with this stuff?

There are so many things in this world that we take for granted. They’ve become sucha part of our everyday lives that they no longer raise even the slightest blip on the radar ofour consciousness. Yet, those same things once instilled a sense of awe and excitement: Theywere the greatest things since sliced bread.

Take, for instance, the CNC machine tool. Not long ago, the mere fact that a millingmachine could automatically carve a finished part from a chunk of raw steel – and do itquickly, accurately and repeatably – would have had even the most jaded machinist oohingand aahing at the accomplishment. Today, even the most advanced machine tools – thosemulti-axis, multi-tasking, high-accuracy, lights-out wonders of modern technology – oftenraise little more than a slight glimmer of interest.

Other examples abound: Imagine the Wright brothers’ reaction to today’s jumbojetliners, or Henry Ford’s response to the modern automobile assembly line. And whatwould Alexander Graham Bell think if exposed to the hordes of men, women and childrenconstantly chatting away on their ever-present cell phones?

Perhaps their response would be: Who in the world came up with this stuff?In this issue of CNC Machining we not only ask that question, but also provide a few

answers. For our cover story we visited Rexam Glass in the United Kingdom. Arguably thelargest glass-packaging manufacturing plant in Europe, the company’s facility in Barnsleyproduces a staggering three to four million bottles each and every day. We show you how theydo it, and provide a bit of bottle-making history in the process.

On the technical side of things, we have a piece on finite element analysis (FEA), apowerful design tool for analyzing stresses and deflections. Once used solely by theaerospace, defense and nuclear power industries, today’s FEA software makes thetechnique accessible to the masses. We give you a brief overview of the process, and showyou how it’s used to make better machine tools.

Better machine tools require better tool paths. Undeniably, modern CNC machines are aquantum leap above their manual counterparts. But according to our friends at Surfware,CNCs still have a lot of untapped productivity potential. To mine that potential, they’vedeveloped a new tool path strategy that disregards traditional machining approaches todramatically increase programmed speeds and feeds. The results are impressive: Watching amachine with their tool paths in action is truly “aah”-inspiring.

Such innovation is what keeps the world interesting, and keeps the industryadvancing. But it’s the fresh blood coming up through the ranks that will ensure our future.For our education piece this issue we visited Rensselaer Polytechnic Institute (RPI). Thenation’s first technical university, RPI was founded to “instruct persons in the application ofscience to the common purposes of life.” In the school’s Multidisciplinary DesignLaboratory, students gain practical, real-world experience as they tackle engineeringchallenges for some of the largest and most innovative companies in the world.

As always, there’s much more. Be sure to look over the latest installment in ourTaking Control series, which delves into the inner workings of the Haas control. In thisissue we explore the Help and Calculator pages. Also check out Cycle Time, for the latestnews and information about Haas Automation, and peruse the Answer Man forsolutions to some interesting applications problems.

There’s a lot to take in. So sit back, relax and enjoy!

26

20

6

On The Cover

The UK’s RexamGlass pumps outnearly 4 million glass bottles eachday, using hundredsof precision moldsmachined on Haas equipment.

Photo by Scott Rathburn

Finite Element Analysis (FEA)is a technique that is used topredict and analyze stressesin a design. It is a vital toolused extensively in theaerospace, automotive,electronics, civil engineering,materials-fabrication, andmachine tool industries. The process was firstdeveloped for use in theaerospace and nuclearpower industries, where thesafety of structures isessential. Today, automobilecompanies use FEA todetermine stresses anddeformation in vehiclesduring a crash. Andelectronics companies useFEA to solve electromagneticequations and predictmagnetic-field strength whendesigning new devices. Infact, modern finite elementanalysis software enablesnearly any engineer toquickly set up a model, run asimulation, and then displaythe results graphically.In the not-to-distant-past,however, stress analysis wascarried out manually, byperforming a series oftedious calculations. Everyforce acting on an object hasa vector associated with it,and each vector/forcecombination requires anindividual calculation todetermine the stress itcauses. The results of theseindividual calculations mustthen be combined in anoverall calculation todetermine the total CNC MACHINING | 3

Finite element analysis (FEA) is a technique that is used to predict and analyzestresses and deflections in a design. It is a vital tool used extensively in theaerospace, automotive, electronics, civil engineering, materials-fabrication andmachine tool industries.

The process was first developed for use in the aerospace and nuclear powerindustries, where the safety of structures is essential. Today, automobile companiesuse FEA to determine stresses and deformation in vehicles during a crash. Andelectronics companies use FEA to solve electromagnetic equations and predictmagnetic-field strength when designing new devices. In fact, modern finiteelement analysis software enables nearly any engineer to quickly set up a model,run a simulation, and then display the results graphically.

In the not-too-distant past, however, stress analysis was carried out manually, byperforming a series of tedious calculations. Every force acting on an object has a vectorassociated with it, and each vector/force combination requires an individual calculationto determine the stress it causes. The results of these individual calculations must thenbe combined in an overall calculation to determine the total stress on a part.

2 | www.HaasCNC.com

Because performing these complex calculations requirestremendous computing power, FEA use in the early1970s was generally limited to high-end industries –

aerospace, defense, nuclear power – with access to mainframecomputers. It wasn’t until the advent of microcomputers (PCs)in the ’80s that FEA began to see widespread use.

In recent years, significant advances in computertechnology and software development have made FEAmethods accessible to the masses. Modern FEA programs aremore powerful and affordable than ever before, and thenumber of industries using them continues to grow.

The engineers at Haas Automation have used FEA toevaluate their designs for quite some time. They use aprogram called COSMOSWorks, which interfaces closelywith the 3D modeling program (SolidWorks) they use fortheir designs. An engineer can open a solid model inCOSMOS and run a virtual stress analysis module against it.Forces can be directed at the 3D model at the same angles andmagnitude that the part or assembly will see during use.Based on the results, the engineer can make modifications tothe component or structure to optimize the design.

On parts that have low stresses, Haas engineers use FEAto focus more on deflections. This is the initial step indeveloping an accurate machine. The accuracy of a machinetool is due to the stiffness of individual assemblies or parts,

rather than their overall strength.Before any new prototype machine is built at Haas, all

major components and structural members are evaluatedusing FEA. This process ensures that every machine built willperform as required, and exceed customers’ expectations.

What Is Finite Element Analysis? Finite element analysis is a numerical technique for

solving a complex set of differential equations. FEA methodsare used primarily to analyze structural, thermal and fluid-flow situations when hand calculations cannot provideaccurate results. This is often the case when the geometry ormodel is very complex.

While it’s not necessary to have a thorough knowledgeof finite element theory to use such programs as COSMOS,some basic theory is required to understand both the physicalproblem and then interpret the results.

The Meat and Potatoes of the ProgramThe FEA program automatically breaks up a complicated

shape into a collection of many simple shapes, or finite elements(the analysis software calls this a mesh). Rather than solving onevery complicated equation, the computer solves a series ofsimpler equations for each of the finite elements, and thentabulates and summarizes the results to provide a solution.

FINITE ELEMENT ANALYSIS (FEA) :Not Just Another Three-Letter Acronym BY ALASTAIR BRENNAN

F EA programs also allow engineers to test new designs andmodify existing designs without having to build actualprototypes. This reduces the cost of testing, decreases the need to

make physical prototypes and speeds up the development cycle.And, because designs can be optimized and thoroughly tested

using FEA, the overall quality of the product is improved and warrantycosts are reduced.

As you can see, the common denominator here is the reduction ofcosts. At Haas Automation, these reductions are passed on to thecustomer in the form of affordable prices for an ever-expanding line ofhigh-quality, high-value, reliable machine tools.

The Bottom LineFinite element analysis has gone from being a technology used only

in very high-end engineering fields to being a powerful and affordabledesign tool used by engineers from every industry.

This does not mean, however, that just anyone can whip up adesign, run it through an FEA program, and have it become the next bigthing in the engineering world. On the contrary, finite element analysisis just one of many tools available to design engineers. It does notreplace an engineer’s knowledge and experience; it complements it.

And there’s more to creating a good design than just eliminatingstructural and mechanical stresses. Heat transfer, fluid flow andelectrostatics will affect a design, as well. But in the end, it takes theengineers’ experience, research into industry trends, the application of newtechnology and feedback from customers to create a successful product.

4 | www.HaasCNC.com

FEA computer programs calculate deflection using theuser’s inputs of geometry, material properties, constraints(locations where the part is fixed or movement is prevented)and loads (stresses). The shape of the element mesh definesthe geometry, and the user enters the strength of the materialand the constraints.

The part design and material define the overall stiffnessof the structure, and the applied loads and given boundaryconditions on the structure result in deflections at variouspoints in each element. Stress results are computed insecondary calculations using the deflection results. Engineerscan use the deflection results to evaluate productperformance, and the stress results to check for failure of thestructure or compliance to safety factors.

Stress or strain results, together with variations inloading and cyclic material properties, help identify areas of

concern within the design. The design can then be modifiedto minimize or eliminate these concerns.

Why Should You Care?Because it results in better products that are optimized for

stiffness, without over-designing them and adding unnecessarymaterial. This, in turn, lowers the cost of the machine.

While the benefits of using an FEA program arenumerous, the end result almost always equates to a superiorproduct and a reduction in costs.

For example, a company can use FEA to simulate theoperating range and function of a design early in thedevelopment cycle to determine if the concept is even viableor on the right track. This can prevent costly redesigns downthe road.

1909: The Ritz methodof numerical analysisis introduced.

1960: The term “finiteelement” is coined andused widely in theaerospace industry.

1943: The Ritz method andcalculus are applied to create“piecewise approximations.”

1953: Use of computersto solve structural problems.

1970: FEA becomes thegeneral method for solvingdifferential equations(stress analysis).

1980: The introduction ofthe PC (microcomputer)allows FEA to be used byvirtually every industry.

“While it’s not necessary tohave a thorough knowledgeof finite element theory touse such programs asCOSMOS, some basic theoryis required to understand thephysical problem, and theninterpret the results.”

“While it’s not necessary to have a thorough knowledge of finite elementtheory to use an FEA program, some basic theory is required both tounderstand the physical problem and then interpret the results.”

These are examples of the types of forces a machine tool must endure during the machining process.As it operates, the machine is subjected to various forces acting toward or against each other.

Machine tool components are analyzed to determine the type of stress they will see, and then testedusing FEA to optimize their design. This ensures that the finished machine will perform as required, andmaintain the necessary accuracy during the machining process.

CNC MACHINING | 5

How did FEA come about?

Gob.

CNC MACHINING | 76 | www.HaasCNC.com

It’s a typical English winter afternoon, slightly overcast and damp, with thetemperature hovering near 5 degrees C (that’s 41 degrees Fahrenheit for you non-metrictypes). Bits of glass crunch underfoot as we make our way across the yard toward thebuilding that houses the forming machines. We pause outside the door to don earprotectors and safety glasses before entering. Then we step inside.

A wall of intense heat rolls over us as we walk through the door, as if from a blastfurnace or foundry. A cacophony of mechanical clatter dominates the aural landscape,assaulting our ears, despite the previously donned protectors. Overlying the din, anunusual sound rises above the clatter. A whoosh of sorts, changing pitch from high to low,emanates from above.

Looking overhead, I discover the source. Three stories up, glowing gobs of moltenglass drop two and three at a time into a network of scoops and troughs, changing fromwhite-hot to yellow to orange as they descend. Each super-heated mass emits anotherworldly screech as it plummets to the equipment below. The individual soundsoverlap and intertwine, bringing to mind tiny meteors screaming through the Earth’satmosphere – like something out of a science-fiction movie.

I widen my view to take in the entire scene. Before my eyes the glimmering globulesof glass disappear into the tops of the towering apparatus, only to emerge seconds latercompletely transformed. The machines before me are called individual section machines –IS machines for short – and their sole purpose is to transform liquid glass into solidcontainers, in this case, narrow-neck beverage bottles.

As I watch this nearly incomprehensible process, one of the first things that crosses mymind – once the overwhelming sense of awe wears off – is this: Who in the world came upwith this stuff?

[ I t ’ s a Technical Term]Story and Photos by Scott Rathburn


identical vessels quickly and easily; the process also greatlyincreased the variety of shapes it was possible to produce.

This blow-mold process remained the primarymethod for manufacturing glass containers well into thenineteenth century. During the 1800s, the typical glass“shop” consisted of three skilled glass blowers and three orfour boys serving as helpers. Using blowpipes and metalmolds, the craftsmen created glasses, bottles, jars and otherglassware.

With the Industrial Revolution came advancements in theglass industry, but primarily to the glass-making process itself– improved glass formulations, better melting furnaces andthe like. The bottle-making process, however, despite gradualimprovements in speed and quality, continued to rely on lungpower and human skill to create the finished product.

As demand for glass containers increased – drivenlargely by food, beverage and drug manufacturers looking

for cost-effective packaging – inventors the world over stroveto develop a mechanical means to produce glassware. By thelate 1800s, patents for semi-automatic bottle machines hadbeen issued in the United States and the United Kingdom.Philip Arbogast of Pittsburgh developed the first semi-automatic press-and-blow machine in 1882, and EnglishmenHoward Ashley and Josiah Arnall developed the first semi-automatic blow-and-blow machine in 1886. (More on thesetwo processes later.)

While these machines automated much of the process,they still required skilled labor to operate them. It wasn’tuntil 1899 that a patent was issued – to Michael J. Owens, an

The manufacture of glass containers is nothing new. Infact, the oldest fragments of glass vases (evidence of hollowglass production) date back to the 16th century BC, inMesopotamia. By 1500 BC, both Mesopotamian and Egyptiancraftsmen were producing glass containers regularly, using acore-mold process in which a core of compacted sand or claywas covered with molten glass. While still hot, the vesselswere decorated by applying strings of different colored glassto create designs, or by rolling them across textured surfacesto create patterns. When the glass hardened, the core was dugout, leaving a hollow vessel.

It wasn’t until around the first century BC that theprocess changed dramatically, with the invention of the blowpipe in Syria. Hollow glass vessels were made by collecting a

gob of molten glass on one end of a long metal tube, and thenblowing on the other end of the tube to introduce a bubble ofair into the glass. The vessel could be shaped and decoratedby rolling and pinching the glass while it was still hot. Thisprocess has changed little over the centuries, and is still in usetoday, primarily by artisans and hobbyists.

By design, glass blowing is a rather imprecise process.Objects are created one piece at a time, and it’s difficult tomaintain any sort of uniformity from piece to piece. For theskilled craftsman, creating one-of-a-kind masterpieces for theprivileged few, this was a desirable situation. But for theworkaday laborer, making glass bottles in quantity, there hadto be a better way.

That better way came courtesy of the ancient Romans, who,with the invention of the two-part mold, developed the firstmethod for mass-producing hollow glass objects. By blowingglass bubbles inside the molds, they were able to create nearly

[A Long Time Coming]

A fish-shaped glass bottle formed using the core-moldprocess. From el-Amarna, Egypt, circa 1350 BC.

© The British Museum/Heritage-Images


employee of the Libbey Glass Company in Toledo, Ohio – for a glass-blowing machine forthe automatic production of glass bottles.

Owens had earlier developed semi-automatic machines to manufacture light bulbs,drinking glasses and lamp chimneys, but these machines still required the glass to be gatheredby hand on individual blow pipes. In 1899, Owens turned his efforts to creating a bottle-makingmachine that would automatically gather glass in the proper quantities, and then produce afinished bottle – all without human intervention.

With the financial backing of company owner Edward D. Libbey, and the support of atalented engineering team, Owens turned his ideas into reality. In 1903, the first Owensbottle-making machine, dubbed Number 4, was ready for trials; and in 1905, the firstcommercial model, the “A,” was offered for production and licensing.

Once the machine proved commercially viable, Owens and Libbey, along with threeothers, formed the Owens Bottle Machine Company to build and license the machines. At thesame time, they applied for patent rights in all other countries outside the U.S. where glasswas made. Soon, Owens machines were in production around the world.

The model “A” consisted of six arms, or heads, mounted on a circular rotating frame. Asthe frame rotated, a series of stationary cams caused the entire machine to oscillate up anddown over a gathering pot of molten glass. Each head carried a blank mold, a neck mold and

Glass, in all its forms, begins as a collection of rawmaterials: sand, soda ash, limestone, dolomiteand cullet (crushed recycled glass), as well asminor ingredients for the refining process. The

materials arrive at the glass plant via truck and rail, wherethey’re stored in huge silos at a batch house.

Although vast quantities of raw materials are used, theymust be weighed out very accurately to ensure the properproportions for the type of glass being made. This is doneelectronically and automatically in the batch house, before thematerials are conveyed to the furnace for melting. Fired bygas, oil or electricity, the furnace produces a temperature of1580 to 1600 degrees centigrade to melt and homogenize theglass, which takes on the order of 24 hours.

From the melting furnace, the glass stream flows to theforehearth, where it undergoes conditioning and is brought tothe proper temperature for the production machines. Plungersshape the conditioned glass stream and force it to the gobbingpoint of the feeder, where synchronized mechanical shears cutthe stream into precise gobs of glass of the same weight as theeventual container. A distribution system of scoops andtroughs delivers the gobs to the IS machine below, where theyenter the blank molds.

Each section of the IS machine contains two sets of molds:

a set of blank molds and a set of forming molds. The blankmold forms the neck of the container and the parison (aprecisely formed pre-shape of red-hot glass).

In the blow-and-blow process, the neck of the bottle isshaped first by blowing the gob of molten glass into thebottom of the blank mold (settling blow), and then a secondblow of compressed air through the newly formed neck(counter blow) shapes the parison.

In the press-and-blow process, the neck of the bottle andthe parison are shaped at the same time by a metal plungerpressing the molten glass against the blank mold. For bothmethods, the rest of the forming process is the same.

The parison is then inverted and transferred to the formingmold, where a blast of compressed air blows it into the finalshape of the container. Once the containers have cooledsufficiently to maintain their shape, take-out tongs transferthem to a conveyor. The entire process takes only a few seconds.

The conveyor transports the cooling bottles throughan annealing lehr, where they’re reheated and slowlycooled to relieve any residual stresses in the glass. Onceannealed, the bottles are individually inspected, bothoptically and mechanically, for dimensional accuracy andquality, and then placed on pallets and protected withshrink-wrap for delivery.

Bottlesin the

MakingBy Scott Rathburn

Continued on page 12

photo cour tesy Owens- I l l i no is (O- I )

The Owens automaticbottle-making machine (above)

arguably was the mostsignificant development in

glassmaking since the inventionof the blowpipe around 50 BC.

CNC MACHINING | 13

Owens solved the problem with the introduction of the“AN” machine in 1912. Rather than the entire machine movingup and down, the “AN” had 10 individual heads that dippedindependently into the gathering pot. The “dip head” designbumped output to an average of 50 bottles per minute, oraround 72,000 bottles in a 24-hour period.

By 1923, according to a study by the National Associationof Bottle Manufacturers, 94 out of every 100 bottles in the U.S.was being made by either semi-automatic or automaticmachinery. The introduction of the gob feeder that same year –a device that provided a rapid supply of consistently sized gobsfor bottle production – added further momentum to theevolution of the automatic bottle-making processes.

But it was the introduction of the IS forming machine in1925 (IS standing alternately for independent section or Ingleand Smith, the machine’s inventors) that took glass containerproduction to the next level.

An IS machine consists of multiple forming sections thatare fed by a central feeding mechanism, rather than a gatheringpot. Since the sections are independent of each other, one or

more can be taken offline for maintenance without affecting theothers. Operating in conjunction with a gob feeder, an ISmachine allows high-volume, simultaneous production ofmultiple bottles from a single machine.

IS machines generally consist of 6 to 12 sections, withsome machines having as many as 16 or 20 sections. Themachines can use either the blow-and-blow method or thepress-and-blow method to form the containers. Double-goband triple-gob production (two and three mold sets persection, respectively) are commonplace, with quadruple-gobproduction also available.

Which brings us to the present: The gob feeder/IS machinecombination is the basis for nearly all automatic glass containerproduction today. Modern IS machines are capable ofproducing upwards of 1 million bottles per day, in myriadcolors and shapes. With large glass-container manufacturersrunning multiple IS machines, that number easily jumps intothe 3 to 4 million bottle range – every day, 365 days a year.

12 | www.HaasCNC.com

plunger for forming the neck, and a finish mold. On each down stroke, a different head wouldcome into contact with the gathering pot, and a suction device – dubbed the “bicycle pump,”because that’s what it resembled – would gather a charge of molten glass into the blank mold.A plunger then pressed into the gather of glass to form the neck of the bottle. Suspended bythe neck, the gather was transferred to the finish mold, where a reverse stroke of the “bicyclepump” blew the glass into the final shape.

The Owens “A” machine could produce 12 pint bottles per minute, or 17,280 bottles in24 hours. By comparison, a shop of six men and boys could produce approximately 2,880bottles per day. The Owens machines also produced a superior product that was moreuniform in weight and size than those produced by hand or by semi-automatic machines.This high-volume production, combined with the uniform height and capacity of the bottles,in turn, led to the development of high-speed filling and packing lines.

Between 1905 and 1914, the Owens bottle machine underwent numerous design changesand improvements, all of which led to faster manufacturing speeds and higher productionvolumes. Ultimately, though, the speed at which bottles could be produced was limited by theconstant dipping of the machines, which caused excessive wear and vibration.

Annealing – A controlled heating and cooling process designed torelieve internal stresses introduced in a glass container during andimmediately after glass container formation.

Batch – A properly proportioned mix of raw materials melted toproduce glass.

Blank Mold – The metal mold in which the parison is formed.

Blow & Blow Process – A method of glass container manufacturingin which the parison is shaped by blowing the glass into a blank moldwith compressed air.

Cullet – Waste or broken glass intended to be remelted. Cullet can beplant generated or recycled from the marketplace.

Finish – The specifically shaped formation of glass surrounding thecontainer opening, which will eventually accept a cap.

Forming Mold (also “finish mold”) – The forming mold, sometimesreferred to as the bottle mold, is the mold in which the bottle is blowninto its final shape after being preformed in a blank mold.

Gob – A lump, or globule, of molten glass with a specific shape,temperature, viscosity and weight. The gob will be processed by theIS machine into a glass container.

IS Machine – A term short for “Individual Section Machine.” The ISmachine is used for the formation of glass containers. It has the abilityto have one or more sections taken out of production for maintenancepurposes, while the remaining sections continue making containers.

Lehr – The long, heated oven through which glass containers move ona conveyor belt so gradual cooling will properly anneal and removestress from glass.

Mold – A set of cast-iron or aluminum-bronze forms fastened on abottle machine to provide a means of shaping a glass container. Partsof the set are tips, neck rings, blank molds, finish molds and bottomplates, with a plunger used in producing wide-mouth containers.

Parison – The preliminary, shaped red-hot glass that hangs from theneck rings as the blank molds open. The parison is also called a“pattern” or “blank.”

Press & Blow Process – A method of glass container manufacturingin which the parison is shaped by pressing the glass against a blankmold with a metal plunger.

Glossary


BigNumbersTheLaw

ofStory by Matt Bailey | Photos by Scott Rathburn

CNC MACHINING | 17

rotary tables, allowing all of the drilling and millingoperations to be performed in a single setup. From there thetwo halves are split and go on to profiling, where the cavitiesare turned and finished. Then, it’s back on to various Haasmachining centres for drilling and engraving operations.

As all of this happens there’s another area in the Rexammachine shop where two Haas SL-20 turning centres are setup in a cell for machining the mould caps. One of the twoHaas turning centres has live tooling to drill holes in the caps,which eliminates having to move the parts to a mill forsecond operations.

“Since we bought the Haas machines, mould tool lead-time has been reduced by approximately 10-15 percent,” saysIllingworth, “equating to 1-2 weeks in real time. Thistranslates directly into our ability to bring new products tomarket faster, a vital factor if we want to stay competitive.”

But “fast,” as Illingworth knows, is only part of the story.“The accuracy of the Haas machines allows us to keep

material costs under control,” he adds. “For example, if aninaccurate mould produces 1 gram of excess glass per unit,multiplied by three million a day, we have a serious problemon our hands. We sell our products by weight.”

Rexam also sells its products by design, pleasingaesthetics being vital to successful packaging. Using Delcam’sPowerMILL CAM software, the company creates tool pathsfor a Haas VF-5TR five-axis trunnion machining centre, whichengraves decoration into the surface of the mould.

“Many of the designs we’re creating simply couldn’t bemade without the Haas trunnion machine and the Delcamsoftware,” says Illingworth. “Our ability to produce exactlywhat our customers want gives us a tremendouscompetitive advantage.”

LeanOperating a two-shift system, Rexam’s mould services

division has recently embraced lean manufacturing, adoptinga one-piece flow format for much of its machining. As oneHaas machine finishes a cycle, the next is also just finishing,and is ready to accept a new component. This concept hashelped Rexam to reduce both its casting stock and its work in progress.

“To maintain our production system, machine reliabilityis paramount. If one of our Haas machines stops it can spelldisaster,” says Illingworth. “Of course, it’s not good for our


In a day and age when the media makesfrequent references to 10-, 11- or even 12-figure numbers – the personal fortunes of afew high-profile individuals, the marketcapitalisation of public companies or thenumber-crunching power of the latestsuper-computer – people have becomeaccustomed to thinking in terms of billions,

even if it does stretch the average imagination to the pointof brain-fade. For the average engineering job shop orproduction line, however, an output exceeding 1000million finished products per year isn’t just difficult tocomprehend, it’s simply inconceivable. For Rexam Glass,it’s business as usual.

In terms of physical size, Rexam claims that itsBarnsley factory is the largest glass-packagingmanufacturing plant in Europe. A total of 13 productionlines manufacture an average of between 3 and 4 millionglass containers every day. These are formed using a seriesof blank and blow moulds, and Rexam estimates that up to£400,000 worth of mould tooling is in use on the factoryproduction lines at any one time.

To manufacture and service the mould tooling for sucha demanding production environment, the companyemploys a total of eight Haas machine tools – including VF-3 and VF-5TR (trunnion) CNC vertical machiningcentres, and SL-20 and SL-30 CNC turning centres –supplied by Norwich- and Leicester-based Haas

Automation Ltd. Roy Illingworth, manager of thecompany’s mould services division, explains the mouldmanufacturing process.

“We buy a casting for each particular style of glasscontainer,” he says. “The material is either cast iron oraluminium-bronze, depending on the final application. Thefirst operation is performed on a Haas VF-3 machiningcentre. We cut the joint faces, rough out the cavities andprepare for hard edging. After a trip to the welding bay, thejob returns to the machine, where the joint faces are finishedand the welds are roughed to within a couple of millimetres,ready for turning. The two halves are then bolted togetherand go on to what we call ‘wasting,’ which is performed ina special cell consisting of a Haas SL-30 turning centre andanother Haas VF-3 vertical machining centre.”

“Wasting” is a Rexam process where the rough castingsare finish machined to fit into the moulding machines.Firstly, all of the outside diameters are turned on the SL-30,which is configured with a purpose-built fixture designedby Haas UK. It uses custom clamping systems in the chuckand mounted to the tailstock to secure the moulds formachining, representing a quick-change system for fast part changeovers.

When this is finished – and while it is still boltedtogether – the operator will transfer the job to the HaasVF-3 machining centre, where all of the external millingtakes place. This VF-3 also has a customised fixturesystem that holds the mould between two Haas CNC

i

mould-making operation, but that’s the least of our problems.If that mould doesn’t leave here and start producing a bottle,we have an idle production line, and we cannot afford for ourproduction lines to stand idle.”

In fact, the production lines at the Barnsley factory donot stop. They operate 24 hours a day, 365 days a year, and inthe event of an electricity failure, the company even has itsown generators.

“The Haas machines have proved to be models ofreliability,” says Illingworth, “which is no mean feat,considering that the material being machined is mostlycast iron.”

As many a machine tool operator knows, machining castiron produces a sludge that can settle and solidify whensaturated with coolant, becoming heavy to transport alongstandard swarf conveyors. Such is the scale of the problem atRexam that Haas UK engineered specially modified swarfconveyors to help the company overcome potential difficulties.

In-HouseThe company has steadily increased the amount of

mould making it undertakes in-house, from 50 percent 15 years ago to nearly 100 percent today. The complexityof the moulds, along with the pressures associated withfaster production speed, higher output and reduced cost,have forced Rexam to carefully consider each of itsmachine tool investments.

“Accuracy and repeatability are particularly vital,” saysIllingworth. “As we took the decision to increase our in-housemould production, we have invested in machine tools that arecapable of producing the tolerance levels demanded by thefactory and our customers. It’s all about keeping pace; it’s nogood having state-of-the-art production lines supported byarchaic machine tools; it doesn’t work like that.”

The latest Haas SL-30 turning centre purchased byRexam replaced an older, retrofitted CNC lathe. In fact, thecompany still operates a further three of these vintagemachines within its machine shop, all due to be replaced byHaas machines in the next year. However, Illingworth pointsout that only two new machines will be required to handlethe equivalent quantity of work.

The decision-to-buy process at Rexam is not bestowedupon one person; the company deploys a team to undertakea thorough investigation and assessment of options, beforereaching a conclusion and making an application to the boardfor investment funding.

“This process has always proved very successful, as isthe case regarding the Haas machines,” concludesIllingworth. “The Haas machines have revolutionised themould services division, and we would have shut down if wehadn’t moved forward. The selection of Haas has been theright decision, and they have served us very well.”

Rexam Glass Barnsley Ltd

+44 (0) 1226 710 211 www.rexam.com/glass



There’s no denying that CNC milling machines represent a quantum leap inproductivity over their manual brethren. Even so, numerically controlled millingmachines still fall short of their true productivity potential.

A bold statement, yes, but the limiting factor in material removal rates is not themachine tool itself, or the cutting tools. Rather, the limiting factor in the productivity ofCNC milling machines is the input to the machines – the tool paths that drive them.

Tool paths force machine tools and cutting tools to perform under the worst possibleconditions. Cutting tools are driven into corners where the machining load increasesdramatically. Sharp directional changes require machine tools to come to complete stops,and to accelerate and decelerate rapidly and often. Feedrates are maintained at the centerof the cutting tool, which does not control how fast the chips are removed, except whencutting in a straight line. Machine tool builders and cutting tool manufacturers have mademany technological advances to better cope with these worst-case conditions, but untiltool path logic is reinvented, these adverse conditions remain – and machiningproductivity is limited.

By Glenn Co leman, V ice Pres ident o f Product Des ign, Sur fware, Inc.

A NEW TOOL PATH STRATEGYTAPS THE TRUE POTENTIAL OFCNC MILLING MACHINES


Existing tool path generators maintain a constantstepover between cuts, and a constant feedrate at the centerof the tool. These two core strategies, though unavoidablewith manual milling, actually limit the utility of numericallycontrolled machines. NC machines have always been capableof running free of these restrictions, but the tool path enginesdeveloped by CAM software vendors – and even the earlycomputer-assisted programming languages, such as APT –keep these strategies not only in play, but front and center. A brief look at these machining dynamics illustrates how atremendous opportunity to increase productivity has beenoverlooked for many years.

Constant Stepover

There is a relationship between a stepover value and atool’s engagement angle with the material. A stepover valueof 50% of the cutter diameter results in 90° of the periphery ofthe tool being engaged with the material. A 30% stepoverequates to a tool engagement angle (TEA) of 66.42°, and a70% stepover yields a TEA of 113.58° (Figure 1). For any givenstepover value there is one, and only one, correspondingTEA. But this is true only when cutting in a straight line with

a constant radial depth of cut. When traversing a sharp,concave corner, the TEA increases by the supplement of theangle of that corner. For example, when a tool programmed ata 70% stepover (113.58° TEA) encounters a 135° concaveangle, the TEA increases by 45° (180° – 135° = 45°) to 158.58°(Figure 2).

Consequently, a tool reaches full burial (180° of TEA)when the angle of the sharp, concave corner equals the originalTEA. So a tool programmed at a 70% stepover reaches fullengagement whenever it encounters a sharp, concave corner of113.58° or less (Figure 3).

These significant increases in tool load are extremelycommon. A tool machining a rectangular pocket with a 50%stepover value reaches full engagement every time it makes aturn. Each such turn requires the machine to come to acomplete stop, however briefly, in order to change directions,as evidenced by the circular dwell marks commonly left on thefloor of a part. As the tool enters the corner, it is rapidly andsignificantly overloaded, increasing the “push” away from itsnatural attitude (parallel to the spindle). It then quickly comesto a stop, where it is rapidly unloaded and attempts to“spring” back toward its natural attitude. As the tool exits theturn, it is then rapidly reloaded, this time to its expected level.

CNC MACHINING | 23

This cycle is what produces the groaning and screechingheard all day, every day, in every machine shop throughout theworld. This obviously adverse machining condition is not onlytolerated, but is accepted as normal. NC programmerscompensate for this with some combination of slower spindlespeeds, slower feedrates, smaller stepovers or shallower depthsof cut, which, in all cases, cause increased machining time.

Constant Feedrate

The other staple of existing tool path generators is tomaintain a constant feedrate at the centerline of the cutter. Butmaintaining a constant feed at the tool’s center causes a non-constant feedrate at the periphery of the tool, where the chipsare actually produced.

A simple analogy can be found on a running track. AnOlympic track has an inside running length of 400 meters.Most tracks have 85-meter straights, and turns that have aradius of 36.41 meters. On the straights, a runner in lane 2keeps pace with a runner in lane 1 (the inside lane) by runningat the same speed. In the turns, however, the runner in lane 2must run significantly faster to keep pace; he must cover alonger distance in the same amount of time. Now, move therunner in lane 2 to lane 8, and he must run dramatically fasterto keep up, perhaps impossibly so. If the inside radius of theturn is reduced from 36.41 meters to, say, 1 meter, the outsiderunner must now run even faster.

The distance between lanes represents the radius of theendmill. The greater this value is, the greater the disparity inspeed. (Imagine a track with many more lanes.) The insideradius of the track represents the tool path radius at thecenterline of the tool. The smaller this value is, the greater thedisparity in speed.

The numbers are dramatic. For example, when a 1.00"diameter endmill, programmed at 100 ipm, traverses aconcave tool path radius of 0.010", the effective feedrate at theperiphery of the tool is 5,100 ipm. Reduce that tool path radiusto 0.005", and the effective feedrate is 10,100 ipm.

Fig. 1Fig. 1

Fig. 2

Fig. 3

Fig. 1For 70% stepover, tool engagement angle (TEA) = 113.58°when cutting in a straight line.

Fig. 2When the tool encounters a corner, the TEA is increased by180° minus the angle of the corner. In this example, thecorner angle = 135°. Therefore, the TEA = 113.58° + (180° – 135°) = 158.58°

Fig. 3Therefore, the tool is at maximum engagement (180°) whenthe corner angle is ≤ straight line tool engagement angle.For 70% stepover, TEA = 113.58° in a straight line.

100 ipm. Dramatically increased programmed feedrates can now be used. Tests reveal thatthe feeds and speeds recommended by cutting tool manufacturers are now obsolete.

At the recent EASTEC show in Springfield, MA, this new tool path engine was usedto drive a Haas VF-2SS – a high-speed VMC with a 12,000-rpm spindle and 1,400-ipmrapids. Using a 0.500" diameter, 3-flute, solid carbide endmill, a freeform shape wasmilled from 6061 aluminum. The tool ran at 12,000 rpm, with a 0.500" depth of cut, 0.375"programmed stepover and a programmed feedrate of 756 ipm! This is triple therecommended feed per tooth for the tool, and the machining was so smooth as to bealmost inaudible. Due to the much lower machining loads, the stress on the tool wasdrastically reduced. After three days of machining, the cutter still looked new.

Since this new tool path engine precisely controls the TEA, the tool never encountersexcess material. Therefore, the shape of the part is irrelevant. For a given tool in a givenworkpiece material, any combination of spindle speed, feedrate, depth of cut andstepover that yields the desired combination of material removal rates and cutting toollife – when cutting in a straight line on the edge of a block – can safely be used on anypart, regardless of its shape.

With this software, it is now possible to fully utilize the full capability of numericallycontrolled machines. Tool paths no longer limit material removal rates. Rather than forcemachine tools and cutting tools to operate under worst-case conditions, this new tool pathengine turns all conditions into best-case conditions.

This new patent-pending technology, called TrueMill™, is only available inSURFCAM Velocity by Surfware, Inc.


In our track analogy, a runner in an outside lane simplyfalls behind under these circumstances. Clearly, the peripheryof a cutting tool has no such option: The effective feed pertooth becomes tremendously out of sync with the spindlespeed. As a result, the chips cannot clear, and the tool breaks.

Recent tool path “innovations” that add small radiusarcs to keep the machine from coming to a stop (most HSMalgorithms), or small-radius circular moves to keep from fullyburying the tool (“trochoidal” milling), actually causedramatic increases in stress and wear on the machine tool andthe cutting tool. To compensate for this phenomenon,whether it is realized or not, NC programmers reduce theprogrammed feedrate, which, of course, slows the entire toolpath. If feedrates aren’t slowed enough, machine operatorsmust diligently man the feed override control to slow the toolin the corners, which is an additional drain on productivity.

Such tool path deficiencies force machine tool builders,cutting tool manufacturers and NC programmers tocompensate for the CAM software industry’s lack of vision.Efforts to develop software to automate the NC programmingprocess, with the apparent goal of eliminating NCprogrammers (a bad idea), divert attention from where itshould be. CAM software should leverage the tremendous

capabilities of numerically controlled milling machines andmodern cutting tools to reduce machine cycle time. This hasfinally happened.

A True Revolution A completely new, patent-pending, tool path engine has

been developed that maintains the tool’s engagement anglewith the material at or below a user-controlled threshold. Thissoftware completely disregards the stepover value, other thanusing it to calculate a TEA. Since the TEA is controlled, ratherthan the stepover, the tool paths look completely unlike thetool paths generated with traditional methods, with the shapeof the machined feature not evident until the final cuts. Theconstant machining load on the tool enables the use ofsignificantly more aggressive machining parameters.

In addition, the system automatically manipulates theprogrammed feedrate to maintain an effective feedratethroughout the entire tool path. Every unique, concave radiusin the tool path has a unique, appropriately adjusted feedrate.In the above example of the 1.00" diameter endmill traversingthe 0.005" radius, the tool path engine adjusts the feedrate atthe center of the tool to 0.99 ipm, which maintains the speedat the periphery of the tool at a constant and uninterrupted

Surfware, Inc.

818-991-1960 www.surfware.com


It was mid-summer of 1807 when someone surprisingly did just that. Before acrowd of interested bystanders and jealous competitors, an outsider named RobertFulton lit a fire and sailed his steamboat up the Hudson River . . . all the way to Albany.In the process, he ushered in a golden age of American technological innovation.

Despite what you may have learned in third grade, Fulton was not the man whoinvented the steamboat. He was the man who made it work. And the distinction isimportant. Details considered trivial by the insiders – how to collect clean water for theboiler, how to insulate the steam pipes for more efficiency, how to keep the bless-edboat from catching on fire – were all taken seriously by Fulton. Those trivial detailsmade all the difference, and when Fulton resolved them, he turned scientific theoryinto practical reality.

“Of course it can be done . . . quite simply, too.”“Then why hasn’t someone already done it?”

– Opined the New York Gazette, October 24, 1806.

INNOVATION ON THE HUDSON –Rensselaer Polytechnic Inst i tute

Two centuries later, we find the Devil is still in the details,so to speak. And all too often, those closest to the technicalproblems just can’t see them. Where’s the person who canthink and do, who has solid theoretical knowledge and a clearsense of the practical? The person who can make it work? Avery modern “old traditional” university in the State of NewYork is educating that person at this very moment.

We have no way of knowing if Stephen Van Rensselaerwas one of the interested bystanders on the banks of theHudson that day in 1807, but it’s a pretty good bet he was.Well heeled, technically inclined and politically savvy, VanRensselaer was, above all, a man who appreciated thepractical side of things. He probably wouldn’t have missed itfor the world.

Born to wealth and privilege in the years just before theColonies became a new country, Van Rensselaer became aHarvard graduate and a four-term member of Congress. Inlater years, he became a driven philanthropist, devoting hisconsiderable wealth and influence to projects he felt would“change the world . . . for the better.”

The greatest American building project of the time wasthe Erie Canal, and Van Rensselaer gave that endeavor all thesupport he could muster. As the engineering marvel nearedcompletion at the top of the Hudson, Van Rensselaer felt theneed to do something more. Four months before the ErieCanal opened, changing the face of American commerce,Stephen Van Rensselaer established the nation’s firsttechnical university on the rolling bluffs above the town ofTroy, New York.

Rensselaer Polytechnic Institute (RPI), as it becameknown, was idealistically chartered in that golden time to“instruct persons in the application of science to the commonpurposes of life.” And so it has. After 180 years of steadygrowth, Rensselaer today is effectively applying scientificknowledge to the “common purposes of life” better than justabout any institution of its kind.

With a tradition of esteemed movers and shakers in itslong history of graduates, Rensselaer is one of the pre-eminent technological universities in the world. An early RPIalum came up with the fantastic idea of the Ferris wheel, andturned it into reality. Another developed an ingeniouscathode-ray tube that made possible the miracle of television.More recently, the university lays claim to numerousastronauts and aerospace engineers, as well as the visionaryIntel engineer now regarded world-over as “the father of themicroprocessor.”

A few years ago, RPI was described as “a place whereMTV and Nintendo meet Sir Isaac Newton.” Given theschool’s current curriculum, however, which spans suchdiverse fields as media arts and nanotechnology, it’s probablymore descriptive to say it’s where iPod meets Einstein.

While continuing to revere the tradition of being theoldest operating school of its kind, RPI has consistently builta reputation for instructing students with the most moderntechnology of the times. Today, that technology includesstate-of-the-art CNC machine tools.

RPI’s renowned Multidisciplinary Design Laboratory,part of the School of Engineering, is where practical, real-

Story and Photos by Richard Berry

CNC MACHINING | 29

world experience meets cutting-edge textbook theory. It’s here that students use whatthey’ve learned to “solve real engineering challenges for some of the world’s biggestand most innovative companies,” the RPI website states.

Integrated into the MDL is a full-featured machine shop. A cooperative effortbetween RPI, Haas Automation and the local Haas Factory Outlet (a Division ofAllendale Machinery), the shop is an official Haas Technical Education Center (HTEC).

Haas Automation has played a growing role in RPI’s educational process formore than 4 years, providing the university with an array of CNC machines, technicalsupport and material contributions. According to Sam Chiappone, RPI’s Manager ofFabrication and Prototyping Resources, “it’s made a significant difference for ourstudents.”

The HTEC is considered the most sophisticated CNC machine shop on campus,and it’s dedicated exclusively to student use. There’s a VF-2 vertical machining center,a Mini Mill, a Toolroom Mill and an SL-10 turning center installed at present. MDLDirector Mark Steiner confides, “When I bring students around to the Haas TechCenter, their first question is, ‘Can I really use those machines?’ Most people who gointo mechanical engineering want to get their hands dirty and actually cut parts,”Steiner adds. “I know I did.”

Students quickly discover that sophisticated machines needn’t be intimidating,and through hands-on experience they learn the operational requirements andpractical limitations of modern CNC machining. As Sam Chiappone sees it, “We needto make sure the engineers who graduate from RPI have a true appreciation for thedifferent manufacturing processes, and for what it takes to make something: What arethe steps involved? What is that person on the shop floor actually going through withprogramming and working with that machine? What are the implications if I put a hole


Hindsight is

or in this case, it can get you

road test of some missed opportunities.

20/20a 200-HOUR

VMC and HMC try-out options:High-Speed Machining (Parameter 315, HIGH SPEED)Rotation and Scaling (Parameter 57, ENA ROT & SC)Spindle Orientation (Parameter 57, M19 SPND ORT)Rigid Tapping (Parameter 57, RIGID TAP)Macros (Parameter 57, ENABLE MACRO)

Lathe try-out options:Spindle Orientation (Parameter 57, M19 SPND ORT)Rigid Tapping (Parameter 57, RIGID TAP)Macros (Parameter 57, ENABLE MACRO)

To purchase any of the options from this demo, contact yourlocal Haas Factory Outlet, or go to www.HaasCNC.com for the authorized distributor nearest you.

How do I try them?

What’s Available?

• The Haas “try ’em before you buy ’em” offer •

Performance-Enhancing

CNCOptions

For Your Haas Machine

Contact your local Haas Factory Outlet or distributor. They will fax,e-mail or walk you through the routine over the phone. It’s a quick 8-step process that will take you only a few minutes. To find your localdistributor, go online to www.HaasCNC.com or call 800-331-6746.

Once activated, your option demo will last for 200 running hours. You will not bewarned when the maximum time is approaching. However, the free demo will not turnitself off in mid-operation, but will shut off at the next power down. Talk to your dealerabout managing your 200 free demo hours by toggling the demo options on and off.

How do I buy them?30 | www.HaasCNC.com

in this part at this particular orientation? Do I need another setup on a machine, or can Ido it in one? It’s really important that our students get practical knowledge in thoseareas. Understanding the whole process helps when designing for complete efficiencies.”

Some students naturally have more of a feel for the CNC machines than others do.“If they’ve gone through the CAM class,” explains Chiappone, “they’re usually prettyproficient at generating code and understanding exactly what’s going on with themachine tools. Students who work on involved projects like the Formula SAE car –they’re very good. With the Haas equipment available for the students to use, we’refinding that more and more students are becoming really proficient with them.”

That proficiency allows students to tackle applications as simple as soap-dishmolds for their senior Advanced Manufacturing Laboratory class, or as complex asconcentric fittings for an industrial sponsor’s magnetic water filter for nuclear powerplants. The students particularly enjoyed the last one, which has been dubbed the“crud catcher.”

Industry-supported projects are a major dividend of the Multidisciplinary DesignLab. Some of the world’s biggest and most innovative companies turn to Rensselaer’sMDL students for fresh “outsider” thinking. In the process, they reap practicalsolutions to some major engineering challenges. General Motors used the student’sengineering knowledge, and their first-hand knowledge of the “Generation Y”consumer, to help redesign the Saturn Ion for more marketplace appeal. GeneralElectric approached RPI for ideas to wring more power and efficiency from their steamturbines. And Lockheed-Martin, which is designing the next generation of nuclear

power plants, needed a practical, magnetic “crud catcher” thatwould allow them to . . . collect clean water for the boiler. That, youmay recall, is one of the small details that Robert Fulton faced andsolved when his project was the “next generation.”

Remarkably, Rensselaer’s 21st Century challenges don’t seem allthat different from those of the 19th Century – they’re just a round ortwo up the spiral of technical evolution. But with one foot plantedsolidly in each of those centuries, RPI clearly is more than just asimple interested bystander on the bank of the Hudson. It’s the onewho will continue to “change the world . . . for the better.” Rensselaer Polytechnic Institute (RPI)

110 8th Street, Troy, NY 12180

518-276-6000 www.rpi.edu

Taking CCNC MACHINING | 33

Or, use the alpha keypad to enter a topic’s single letter designation to jump directly to itspage. Most of the topics are pretty self-explanatory. Give them a quick look now, andyou’ll know what information is there if – or more likely, when – you need it later.

On the newest Haas controls (starting in June of 2005), the Help feature got even easier touse. The same initial Help page gives you a quick summary of information, but you can also nowsearch for a topic or a word within the Help Manual. This is similar to the Help feature on adesktop computer.

Pressing the HELP/CALC button a second time takes you straight to theCALCULATOR pages. Here you’ll find five interesting screens designed to make the taskof programming linear moves, circular moves, and speeds and feeds on the machine mucheasier. Use the PAGE UP and PAGE DOWN buttons in the cursor group to step throughthe calculators.

Each calculator page has a simple math calculator in the upper left corner. Values areentered using the numerical keypad and the WRITE/ENTER key, and the desired mathfunction (LOAD, +, -, *, /) is selected by using the left or right cursor button to highlight it.

To perform a simple computation, highlight the LOAD function first, and then enter anumber with the keypad and press WRITE/ENTER. Then, highlight the desired mathfunction (+, -, *, /), and enter a second number using the keypad. Pressing WRITE/ENTERwill perform that calculation and show the result in the calculator box. To perform multipleoperations in sequence, simply repeat the process.


There’s no argument that computer numerical controlhas made modern machine tools unimaginably productive,or that interfaces like the Haas control have made them easierto operate than ever before. But certain things remainunchanged. Although CNC puts never-before power andprecision at your fingertips, it’s still “get the job done” know-how that defines a good machinist. At Haas, that’s one areawhere the “computer” part of CNC really shines. Inside thatfamiliar gray box there’s a wealth of practical informationand powerful features to help you get the job done.

In the last issue, we presented a general introduction tothe Haas control. But, as we hinted, you’ve only seen the tipof the iceberg. In this issue, we’ll dip below the waterline a

bit, and explore some features more deeply. Again, if you’renew to Haas machines, this article’s definitely for you. Buteven if you’re a longtime user, you stand a good chance ofdiscovering a nugget or two you may have overlooked.

This time out, we’re directing your attention to theHELP/CALC button. You’ll find it in the lower right cornerof the DISPLAY group in the middle of the keypad. Press thisbutton once, and you’ll find a 27-page mini-manual brieflyoutlining nearly every function of your machine.

The first page, titled HELP FUNCTION, provides acomplete directory of topics, along with simple instructionsfor finding them. To find each of the topics in order, simplyuse the cursor keys or the jog handle to scroll down the page.

TAKING CONTROL Part IIHelp Screens and Calculators

By Er ic Bowman and R ichard Ber ry

In addition to the basic calculator inthe upper left, this section has fourspecialized calculators to help solvetrigonometric problems with triangles,circles and tangents, as well as aspeeds-and-feeds calculator.

Taking CControl CNC MACHINING | 3534 | www.HaasCNC.com

The basic calculator will also accept longer mathematical equations that can be typedin on the input buffer, such as 0.25*8/0.25+4-2. When a problem has multiple steps,highlight the LOAD function first, and then enter the complete equation, using thenumerical keypad for both the numbers and the math operators (0.25*8/0.25+4-2). PressWRITE/ENTER after the entire equation is entered to perform the calculation (=10). The equation is evaluated by doing multiplication and division first, and then theremaining operations.

This internal calculator has the advantage of allowing you to copy and paste yourresults directly into the program you’re working on, or into one of the specializedcalculators we’ll discuss later. There’s no need to transfer numbers manually and risktransposition errors from re-entered data. We’ll explore this more in a paragraph or two.

In addition to the basic calculator in the upper left, this section has four specializedcalculators to help solve trigonometric problems with triangles, circles and tangents, aswell as a speeds-and-feeds calculator.

The first screen that comes up is the triangle calculator. Begin entering the lengthsand angle values for your problem triangle, and when enough data has been entered, thecalculator will solve the triangle and display the remaining values. Use the UP andDOWN arrow keys to select where to enter your numbers. Then use the numericalkeypad and press WRITE/ENTER to enter each number. You cannot write over a

Most of the topics are prettyself-explanatory. Give them aquick look now, and you'll knowwhat information is there if - or more likely, when - you need it later.

number that has a highlighted title next to it, because that is a calculated number. Toenter a different value over that calculated number, you must clear one of the otherentered numbers. To do this, press SPACE and then ENTER.

If you’ve arrived at one of your entry numbers using the basic calculator, you canmove that result into any highlighted line of the specialty calculator box by pressing theF3 key. You can also reverse that trick. To copy any highlighted value from the specialtycalculator into the basic calculator’s window, press F4. Whichever math operation ishighlighted (LOAD, +, -, *, /) will be executed at the same time. Then you’re free to add,subtract, multiply or divide the value using the basic calculator.


To try out this copy-and-paste trick, switch to the EDIT mode (press EDIT) to viewthe program you’re working on. Press F3, and the value that’s in the calculator box willshow up at the bottom left of the EDIT page on the data entry line, ready to be enteredinto your program. You’ve now come full circle, or in this instance, full triangle, withoutever touching paper or pencil.

The next screen really will take you full circle. Press the PAGE DOWN button and thetriangle calculator page changes to the circle calculator. This screen works almost exactly likethe last one, but even better: The circle calculator generates sample G code in the process.You’re given code for circular moves in absolute and incremental commands. Simplyhighlight the line that you desire, switch to the EDIT screen and press F3 to copy the selectedline from the circular calculator to the data entry line, ready to be inserted into your program.

Press PAGE DOWN again, and you’ll discover the third specialty calculator, oftenreferred to as the “milling and tapping” (turning and tapping on lathes) calculator page.This calculator may be the most useful. On mill controls, the screen heading readsMILLING; on lathe controls, it reads TURNING. Enter recommended surface-speed andchip-load values for the material you’re cutting, along with the diameter of the part ortool and the number of flutes. The control will calculate the rpm and feedrate based onthe numbers you entered. You define certain values, and the control will calculate the rest. This comes in handy when programming at the machine, or when fine-tuning aprogram that’s already running to make it run better.

The MILLING version of this screen includes a field called MATERIAL that providesrecommended surface-speed and chip-load values for 21 different metals. Use the LEFTand RIGHT cursor keys to scroll through the list for materials as diverse as “Gray Class20 Cast Iron” and “Cobalt Based Heat Resistant Alloy.”

The lower half of this same “speed and feed” screen contains a straightforwardcalculator for computing thread pitch, rpm and feedrate values for rigid tapping. Enterany two values, and the calculator will figure out the third.

The last two calculator screens help solve additional trigonometry problems.Successive PAGE DOWN presses reveal the CIRCLE-LINE-TANGENT and CIRCLE-CIRCLE-TANGENT pages. These screens let you determine points of intersectionbetween a circle and line meeting at a tangent, or between two circles and the tangentiallines connecting them. Such problems appear more often than we assume, and areawkward to solve without a calculator.

The CIRCLE-CIRCLE-TANGENT situation is the most involved, because there arefour points that are tangent within two lines and two circles. Entering the XY location andthe radius for both circles will give you the four tangent points in both X and Y axes.Pressing F1 will toggle you between the two different solutions. Then follow dataprompts to enter “F” (from) and “T” (to) point coordinates, and you’ll be given anautomatically generated G-code solution. As before, you can transfer the line of G-codeinto your program, in EDIT mode, by pressing F3 to paste the highlighted code into thedata input line. In nearly no time, your interpolation command is ready to go.

In addition to these useful calculators, you can access two more useful screens withthe HELP/CALC button. Pressing the button a third time reveals a complete decimal andmetric-equivalent drill-and-tap chart. Scroll down to find fractional, numbered and letterdrill sizes up to 1", along with tap sizes and metric equivalents.

Pressing HELP/CALC again will display a real-time clock showing the current dateand time. This is an easy location to change the date and time on your machine so that theinformation recorded on your machine is correct.

We realize that most, if not all, of the information found in the HELP/CALC screensis also printed in your Haas Operator’s Manual or a good machinist guidebook. But whenyou’re operating a Haas machine, the control is right in front of you, and there’s no needto waste time searching elsewhere. Just press a button, and you’ll most likely find youranswer. The HELP and CALCULATOR features were designed into the Haas control forone important reason – your convenience.

This series continues in the next issue, where you’ll discover still more of the hiddenpower in the Haas control. Features we’ve covered are found in the latest versions of theHaas control software. If you own an older machine or an earlier version of the software,check with your local Haas Factory Outlet. It may be a simple task to upgrade your unitto include these latest resources.

This article is the second in a series that will examine themany advantages of the Haas control. The information you’llfind here can also be found under the solutions/applicationsmenu on the Haas Automation website, www.HaasCNC.com.Check us out there if you can’t wait for the next installment!

Taking Control

CNC MACHINING | 37

CNC MACHINING | 39

Company Ships 50,000th Machine

Haas Automation, Inc., the largest machinetool manufacturer in the U.S., is pleased to reportthe company’s latest milestone: The production,sale and installation of the 50,000th Haas CNCmachine tool. Machine number 50,000 – an SL-20APL CNC turning center with automaticparts loader – came off the production lineFebruary 16. Bearing a commemorative plaque,the machine went to Western Saw of Oxnard,California. A leading manufacturer of saw, tube and laser technology for more than 60 years, Western Saw is a neighbor of HaasAutomation’s. The SL-20APL is Western Saw’sfifth Haas turning center.

New Expansion: Facility to Top 1 Million Square Feet

Haas Automation has begun construction of a new211,000-sq-ft building at its headquarters and manufacturingfacility in Oxnard, California. The new addition representsthe third building expansion in 9 years for Haas, and willpush the company past the million-square-feet milestone.

“That’s why we bought 86 acres when we moved here,”explains Haas General Manager Bob Murray. “We plannedthat, as our business grew, we’d put up new buildings toexpand our capabilities.”

With worldwide demand for its products reaching all-time highs, the company’s sales have more than doubled overthe last two years, driving production to record levels. Haas

now is on target to produce a staggering 10,000machines in 2005 – a number to challenge anymachine tool builder in the world.

“This new building will serve as a warehousefor component parts, as well as inventory offinished machines,” continues Murray, “freeingexisting space for more manufacturing. Itscompletion in February (2006) will coincide withthe delivery of millions of dollars worth of newequipment we purchased at IMTS last year. Thisexpansion will give us the additional machine shopcapacity and mechanical assembly space we’llrequire to continue our growth.”

New Haas Technology

EC-400 HMC with Pallet PoolThe new Pallet Pool for the Haas EC-400

caused much excitement at WESTEC in April.Customers agree that the Pallet Pool provides a new dimension of affordable, flexiblemachining capabilities. The Pallet Pool will beoffered as part of a new, packaged machinecalled the EC-400PP. The EC-400PP willinclude the 6-pallet Pallet Pool, 70-tool side-mount tool changer and belt-style chipconveyor. The Pallet Pool is graphicallyintegrated with the machine control throughthe Pallet Schedule Table (PST) page under theCurrent Commands display. The machine will also include agroup of control options of high value in flexible machiningoperations. Currently, the Pallet Pool HMC is scheduled forfirst deliveries as early as October of this year. (See it movingonline at http://www.haascnc.com/news_videos.asp#news)

The EC-500 HMC – A Late Summer BlockbusterHaas Automation’s new generation of horizontal

machining centers – the EC Series – is designed to meet theneeds of today’s customers right out of the box, withoutrequiring them to invest in a lot of expensive options. Theperformance is built into the machines.

The latest addition to the Haas EC Series is the EC-500. It features a 32" x 20"x 28" work cube, dual pallet changer with 500 mm pallets and a built-in, high-precision palletindexer. The machine comes standard with an 8,000-rpm, 40-taper spindle powered by a 20-hp vector dual drive system.Also standard are a 40-pocket side-mount tool changer, 1000-ipm rapids, a floppy disk drive, 1 MB of program memory anda high-volume coolant system. To eliminate downtimeassociated with manual chip removal, the EC-500 is equippedwith a triple-auger chip conveyor system that removes chipsfrom the enclosure quickly and efficiently.

For added performance, a 12,000-rpm spindlepowered by a 30-hp vector dual drive system isavailable as an option. This spindle provides additionalhorsepower for heavy cuts, as well as 50% more speedfor high-speed machining operations. Both spindlesfeature a unique inline, direct-drive system that couplesthe motor directly to the spindle rather than using belts,and the on-the-fly wye-delta switching provides plentyof low-end torque and a wide constant-horsepowerband, without having to stop the spindle to changewindings.

The EC-500 comes standard with a high-precision,face-gear pallet indexer (Hirth-type coupler) thatprovides 1-degree indexing. The machine’s enclosureallows a maximum part swing of 29.5" on the indexer,

cycle TimeCNCMACHINING


Haas News That’s Fit To Print

Haas Automation General Manager Bob Murray (center) presents the 50,000th Haas CNC Machine commemorative plaque to Kraig (left) and Kevin Baron,President and CEO of Western Saw, respectively.

cycle TimeCNCMACHINING

with a maximum swing of 71" for the pallet changer. A full4th axis is also available.

The servo-driven pallet changer on the EC-500 swapspallets in just 9 seconds, and each 500-mm pallet has a loadcapacity of 1,000 lb (660 lb with full 4th axis). A separate loadstation allows the operator to safely load/unload parts orchange fixtures on one pallet while parts are being machinedon the other, keeping spindle run time at a maximum.

70-Pocket SMTCTo support automated machining on the EC-400 and

EC-500 HMCs, Haas now offers a 70-tool side-mount toolchanger. The 70-tool changer features 1.6 second tool-to-tooland 2.8 second chip-to-chip times. The SMTC 70 will allow amaximum tool diameter of 2.75" with all pockets full, and 6"with adjacent pockets empty. Maximum tool length is 12" andmax tool weight is 12 pounds.

More Good Tool NewsIncreased tool capacity for EC-1600 series HMCs is on

the way. The new 50-tool, 50-taper tool changer will beavailable in limited quantities for delivery in mid-August thisyear. Maximum tool diameter will be 4" with the tool changerfull and 10" with adjacent pockets empty. Maximum toolweight will be 30 pounds.

An Office Mill with Larger TravelsMore and more industries are discovering the

advantages of CNC machining, but many are unable to fit a“normal” CNC machine into their facility. The new OM-2Office Mill provides the solution.

This ultra-compact machine is small enough to fitthrough a 36" doorway, and can be moved easily with a palletjack or equipment dolly. With its small size and light weight,the OM-2 also fits into most freight elevators, and with theoptional caster kit, it can be rolled from one location toanother. The machine runs on single-phase power (240 VAC).

The OM-2 features a work envelope of 12" x10"x 12"(xyz) and a 20"x 10" T-slot table. In standard configuration,the machine comes with a 50,000-rpm brushless micro motorspindle. For higher-production work and added flexibility, aHaas-designed ISO 20 spindle (40,000-rpm) and 20-pocketautomatic tool changer are available.

For full 4th- and/or 5th-axis operation, Haas hasdesigned a pair of ultra-compact rotary tables that fit easilyinto the OM-2’s work envelope. The HRT110 is a single-axisrotary table, and the TR110 is a dual-axis trunnion table.Both units index at up to 300 deg/sec, and provide 65 ft-lbof spindle torque. They each feature a 110 mm (4.33") platterthat accepts a variety of workholding and fixturing options.

For facilities needing turning capabilities as well, Haasalso offers the equally compact OL-1 Office Lathe. It featuresa 5-hp (peak) spindle that spins to 6,000 rpm; the 5C threaded

spindle accepts a number of optional chucks. The machine’shigh-speed cross slide features travels of 12"x 8" (x, z) andaccepts a variety of gang-style tooling.

Extended Y-Axis Machines Expand VMC Line-Up To meet the needs of shops wanting additional Y-axis

travel without stepping up to a much larger machiningcenter, Haas Automation now offers two new extended Y-travel vertical machining centers.

The VF-2YT features travels of 30" x 20" x 20" with a36" x 18" table – an increase of 4" in Y over the standard VF-2.The VF-3YT has travels of 40"x26"x 25" with a 54"x 25" table– up 6" in Y from the standard VF-3. Both machines comestandard with a 7,500-rpm spindle powered by a 20-hp vectordual drive system. A 20-pocket carousel-style tool changer isalso standard.

As with all Haas VMCs, a large selection of high-productivity options are available to tailor the VF-2YT andVF-3YT to the specific needs of each shop, including 10,000-rpm, 15,000-rpm or 30,000-rpm spindles. For heavy cuttingoperations, a two-speed gearbox option that yields 250 ft-lb oftorque is also available. Other options include a chip augersystem, programmable coolant nozzle, high-speed machiningwith full look-ahead, a hard disk drive with Ethernet interfaceand USB support, a side-mount tool changer and much more.

Expanded Line of High-Speed VMCs for Mold MakersFollowing on the success of the VM-3, Haas expands its

new line of VMCs designed for the mold industry. Thecompany’s latest entry is the VM-2, a high-performancemachine with a 30" x 20"x 20" work cube, 36"x 18" table,12,000-rpm inline direct-drive spindle and a high-speedcontrol with full look-ahead.

Like all Haas VMCs, the VM-2 features massivecast-iron construction. Heavy internal ribs on thecastings increase rigidity and damp vibrations. High-precision linear guides on all axes further increaserigidity and stiffness, while providing a low coefficientof friction and long-term reliability. High-speedbrushless servos, combined with fine-pitch ballscrewsand high-resolution digital encoders, ensure ultra-precise positioning and extreme repeatability.

The VM-2 is equipped with a 12,000-rpm, 40-taperspindle that uses a unique inline, direct-drive system thatcouples the motor directly to the spindle rather than usingbelts (a major source of heat). This results in less vibration,less heat and less noise than other drive systems, providingexcellent surface finishes, extreme thermal stability and quietoperation. Powered by a 30-hp vector dual drive system, thespindle produces plenty of low-end torque, as well as thespeed necessary for high-speed machining. On-the-fly wye-delta switching provides a wide constant horsepower band.

To ensure thermal stability, coolant is circulated througha jacket in the VM-2’s head casting to remove heat generatedby the spindle. The headstock is also lined with insulatingmaterial to prevent radiated heat from affecting the casting,and air is circulated through the entire assembly for additionalcooling. An electronic thermal compensation algorithm in theHaas control accurately models ballscrew heating from highduty cycles and automatically corrects for any expansion thatcould cause positioning errors. Available options includelinear scales, Visual Quick Code probing and expandedprogram memory (up to 16 MB).


service engineer can perform a ball bartest for you. A properly maintained and operated Haas machine, though,will hold the factory tolerances formany years.

If you do work for certainindustries, however, such as aircraft,aerospace and defense, you may berequired to calibrate your equipmentregularly in order to maintaincertification. We have numerouscustomers who make parts forcompanies such as Boeing, GeneralElectric and Pratt & Whitney, and haveto meet this type of requirement.Typically, these customers mustperform ball bar testing twice a year,and their Haas machines typically meetthe required specs with no problem.

Since we recommend that ball bartesting be done by a trainedprofessional, we do not publish acalibration procedure for ourcustomers. If you’re interested inunderstanding the procedure better,just ask the next Haas Service engineerwho visits your shop.

Sincerely,Haas Applications

• • •

Dear Applications:

I have been reading the macroprogramming section of theOperator’s Manual, and I see it ispossible to use the DPRINTstatement to print to a serial printerattached to the Haas control. Is itpossible to write to a text file on thecontrol’s floppy disk drive, or would

I need to connect a PC to themachine and write to something likeWindows Terminal?

Alan

Dear Alan:

While it is not possible to use theDPRINT statement to output data tothe control’s floppy disk drive, you arein luck; you can connect a PC to yourHaas machine’s RS-232 port andoutput data that way. You will need anull modem cable andcommunications software for your PC.If you like, you can use WindowsTerminal. Simply follow theinstructions in your manual to connectthe PC to the machine. Then start yourcommunications software, and you’reready to start using DPRINT.


• • •

Dear Applications,

Is the Haas mill control capable ofutilizing feed-per-revolution mode?

Thanks,William Alvarez

Dear William:

Yes, this is a new feature of theHaas control. G95 will interpret anyfeed value as Feed Per Rev. When G95is active, a spindle revolution willresult in a travel distance specified bythe feed value. If Setting 9,DIMENSIONING, is set to INCH, thenthe feed value (F) will be taken asinches/rev. If Setting 9 is set to MM,then the feed will be taken as mm/rev.The G95 mode will stay effective untilanother feed mode, such as G94, FeedPer Minute, has been specified.

Note that the default at power-upis G94. Feed Override and SpindleOverride will affect the behavior of themachine while G95 is active. When aspindle override is selected, anychange in the spindle speed will resultin a corresponding change in feed inorder to keep the chip load uniform.However, if a feed override is selected,then any change in the feed overridewill only affect the feedrate and notthe spindle. A command block thatcontains a tap cycle will ignore anyfeed and spindle overrides, andperform that block at 100%. Setting 56,RESTORE DEFAULT G, willdetermine whether or not an M30should reset the Feed Per Rev mode. If


Dear Applications:

It would save me a lot of time if Icould edit another program while I’mmaking a part. Is it possible to edit orload a new program while my VF-3 isrunning a different one?

Art Contreras

Dear Art:

Yes, you can use Background Editto create or edit a program whileanother program is running. (In fact,you can even edit the program that’srunning, although the changes won’ttake effect until after the machinereaches an M30.) In MEM mode, fromthe PRGRM display, call upBackground Edit by typing in theprogram number you want (Onnnnn)and pressing F4. This will bring up theprogram you requested on the screenand open it for editing. When you’redone editing, push F4 again to go backto the program that’s running.

The easiest way to load aprogram is using the I/O menu in theAdvanced Editor (EDIT mode, then F1to activate the menus). You can onlyuse EDIT mode when there is noprogram running, however, so it is notpossible to load a program whileanother one is active. (If you have theHD/ENET option, you have to loadprograms from LIST PROG mode,which, again, can only be done whenno program is running.)


• • •

Dear Applications:

We use 303 stainless steel. Is thatthe stainless steel I or II in the Haasmilling calculator? Also, on the samecalculator page, the recommendedchip load for both steel I and II is0.002" to 0.004", while therecommended surface feet per minuteis 300–550 sfm for steel I and 275–525sfm for steel II. Why is there only a0.002 range for chip load, but a 250range for sfm?

Dan Bohm

Dear Dan:

The milling calculator gives a rangeof recommended values that are typicalfor machining a specific material. It doesnot define an exact value because it hasno way to know what your particularmachining conditions are. If you’re notsure what values to use, you can startwith the lowest ones and increase themas needed. Presumably you’re using acarbide tool – the values you mention

fall within the range for that typeof tool.

For 303 stainless, usingstainless steel II in the calculator

would be a good starting point.Remember, the values given in the

milling calculator arerecommendations. There are manyvariables in machining, so you mayneed to use values smaller than theserecommendations. The Machinery’sHandbook discusses details andadjustments to many different cuttingconditions.


• • •

Dear Applications:

What is the recommendedcalibration period for Haas machine?Do most customers get their machinescalibrated periodically, or only afterthey start experiencing problems? Doyou publish a calibration procedure?

Bill Garcia

Dear Bill:

All Haas machine tools use high-precision linear guides on all axes, andevery machine is fully calibrated beforeit leaves the factory. Unlike box ways,linear guides do not wear over time,and therefore maintain accuracythroughout the life of the machine.

If you wish to verify yourmachine’s accuracy for your own peaceof mind, most HFOs offer a preventivemaintenance program that includes anannual ball bar check. A certified Haas

the ANSWER M NCNCMACHINING


programming with a CAM system, setup the post processor to output inversetime feedrates (G93) during 4-axismachining. The CAM system willdetermine the distance the tool tiptravels in each block, and outputinverse time feed values to controlboth linear and rotary motion based onyour desired feed per minute (G94).Your CAM system distributor can helpyou set up your post processor.

If you are not using a CAMsystem, we would suggest adjustingSetting 34 for one of the diameters andprogramming the correct feedrate.Then, modify the feedrate for theother diameters.

Example: If you want to mill at 10inches per minute on a 5" diameter, a3" diameter and a 2" diameter, setSetting 34 to 5.0 and program F10.0 for

the 5" diameter. On the 3" diameter,program F16.6667 (5 ÷ 3 = 1.6667;1.6667 x 10 = 16.6667). For the 2"diameter, program F25.0 (5 ÷ 2 = 2.5;2.5 x 10 = 25.)


• • •

Dear Applications:

Do you have software that willsimulate a new program on a PC, andshow the same alarms that I would getfrom the Haas control? We programusing a CAM system, but we still have afew problems when we load a programinto one of our Haas machines (we havefive), and then it takes up time on themachine to troubleshoot the program.

Tony Palazzo

Dear Tony:

Given the number of Haasmachines your shop has, it might beworth your while to invest in a Haascontrol simulator (you now get bothlathe and mill capabilities in onesimulator). While you can writeprograms on a PC and easily transferthem to your Haas machines, we donot have PC software that willsimulate running a program.

That said, if you’re getting thesame alarms every time you send anew program to the machine, thosealarms can probably be fixed bymodifying your CAM system’s postprocessor. Send both the original G code that your CAM system

generated, and the modified G codethat doesn’t alarm out, to your CAMdealer. With this information, they canmodify your post processor.


• • •

Dear Applications:

We are investigating the purchaseof a vertical CNC for high-speedmachining. Are any special G codesneeded for HSM on a Haas machine,like they are on other machines? Also,HSM hardware is typically faster (i.e.,speeds, feeds, etc.). What would be thedifference in software?

Leo Pawelczyk

Dear Leo:

No special G codes are needed forthe Haas control to utilize high-speedmachining. The Haas HSM option isenabled electronically, via a codeentered into your control. This meansthat no special software is required forthe HSM option.

With HSM, shorter cycle timeswill be realized for surfacing programsthat use shorter strokes at higherfeedrates. The Haas control achievesthis via the ability to look ahead up to80 blocks of code. The controlanticipates vector changes, anddecelerates and accelerates moreefficiently, thus reducing cycle time.


this setting is enabled, then an M30 atthe end of a program will reset thismode to its default G94, Feed PerMinute, mode. Alarm 309, EXCEEDEDMAX FEEDRATE, will be generated ifthe combination of spindle speed andfeed value (F) exceeds the limit specifiedby Parameter 59, MAX FEED IN/MIN.


• • •

Dear Applications:

Could you help me with aprogram example for my SL-30? Iwant to use G76 for a tapered pipethread without a thread chamfer. It’s a1.25 NPT thread, 0.875" deep. Thanks!

Larry Cho

Dear Larry:

The taper is 3/4" per foot, so:1) 0.75 ÷ 2 = 0.3752) 0.375 ÷ 12 = 0.031253) 2nd tan–1 of 0.03125 (need a

calculator for this) = angle of 1.7899degrees. This is the taper of the thread.

Now determine the minordiameter, which is X1.161 at Z0 (theface of the part). Determine the Xposition at Z0.5, which is X1.1785, andthe X value at Z-0.5, which is X1.1435.Then:

1.1785 – 1.1435 = 0.0350.035 ÷ 2 = 0.0175, which is your

positive I value. The rest should be easy.%

O00005 (1-11.5 PIPE THREAD) G54 T101

S1000 M03 G00 X0.95 Z0.5 M23 (or M24 for chamfer off) G76 X1.1785 Z-0.5 I0.0175 K0.03D0.01 F0.0869 G28 M30 %

You can use a CAM system orthe calculator on the Haas controlto make points, lines and angleswith which to determine X values.


• • •

Dear Applications:

I’ve been running a program onour VF-2 that was written for a partmade from stainless steel. I would liketo run the same program on a titaniumpiece, but set an override for bothspeed and feed to 60%. My concern isthat there’s a rigid tapping operationinvolved – will the overrides affect theG84 commands? Can I do this withouthaving to go through the wholeprogram and change everything?

Josh Alstead

Dear Josh:

There is one exception to theoverride keys: tapping canned cycles.The override keys will not affectfeedrates or spindle speeds within G84(or G74) canned cycles. Fnnn andSnnnn values on the G84 line will runas programmed.


• • •

Dear Applications:

I have a Haas TM-2 ToolroomMill with an HRT 160 rotary table.When I do rotary milling, I programthe feed in inches/min, and let Setting34 correct the feed for the diameter. If I have two or more diameters thatI’m milling on, how do I correct thefeed for the different diameters? Isthere a method of changing Setting 34in the program? I understand that thisis possible using an “R” or “Q” valuewith G107, but I program my rotarymotion using “X” and “A” rather thancylindrical mapping. What should Iuse to calculate feed for the varyingdiameters? Any help that you couldgive would be great.

Thank you,Jeff Conrad

Dear Jeff:

Although it’s not possible tochange Setting 34 from within a G-code program, there are two goodways to work around this. If you are

the ANSWER M NCNCMACHINING

You can order a mill/lathe simulator from yourHaas distributor.

RELENTLESS.

Documents

CNC Magazine