Charmilles Leads a New Millennium of EDM ... - die sinker edm · manager of tool and die at VEKA. ... to supplement the Wire EDM service. Two years later, CNC Sinker EDM and CNC Small

Inside This Issue:

VEKA Case Study..............................2

Quality EDM work is paramount to VEKA’sworldwide operations.

AcuCut Case Study ......4

Speed, automation anddependability add up tosuccess for AcuCut, Inc.

Business Forecast Survey............................6

Business seems to be goodif you judge by theAMBA’s most recent business forecast survey.

SEKAM TechnologiesCase Study..................10

Robofil 6030 wire-EDMkeys SEKAM Technologiesexplosive growth.

Used Equipment.........13

Charmilles’ UsedEquipment web page

Charmilles Open House...........................16

Higher productivity:Charmilles EDMs unveiledat Open House.

Machining Carbide on aWire EDM....................18

Grinding is not the optionto achieve good tool lifewhen machining carbide.

www.charmillesus.com

Spring 2001

Charmilles Leads a New Millennium of EDM Technology


Spring 2001

VEKA is one of the world’s leadingextruders of vinyl profiles for the win-dow and door industry. One ofVEKA’s top customers is RepublicWindows and Doors. VEKA’s growthin the U.S. in 2000 paralleled that ofthe strong U.S. economy. Eighty fivenew employees were added lastyear alone, sales growth figures hitinto the double digits, and theFombell, PA., plant was expanded tojust under 600,000 square feet ofspace.

That plant hums with activity, running24 hours a day, seven days a week.The first step for VEKA is to develop a precision tooling system. This iswhere wire EDMs come into play.

And quality EDM operations are critical.

“It’s essential,” agrees Pat Racioppi,manager of tool and die at VEKA.

“It’s the first step during the produc-tion of precision extrusion tooling. It’s the core of how we build accu-rate tooling. The geometry is the mostimportant and critical thing in theextrusion business.”

For VEKA, it’s a ‘Baker’s Dozen,’ ofCharmilles machines. The companyhas 13 Robofil 330F machines. “Wewouldn’t have 13 of them if weweren’t certain they do exactly whatwe need them to do,” Racioppi says.

Jim Nagle, Charmilles’ district man-ager for the Northeast says, “VEKA isa great customer and they’re greatindividuals to deal with becausethey’re very knowledgeable in theirfield. It makes it very easy to workwith them.”

Racioppi feels that compared to thegeneral marketplace, the Robofil

2

Quality EDM Work is Paramount to VEKA’sWorldwide Operations


Pat Racioppi, Manager of Tool and Die at VEKA

330F was built for extrusion die making. He lists four features thatseparate the 330F from the rest of the EDM pack.

The first is the table’s rigidity. It is notuncommon for VEKA to work withlarge blocks of steel that will be onthe table for 60 to 100 hours at atime.

“The table on the 330F is reallyalmost the kind of a table that youwould see on a milling machine,”Racioppi says. “It can support heavyloads and support them in a stablemanner for long periods of time.”

When heavy parts require top-loading into the machine tool, the330F really shines. Among all EDMmanufacturers, Racioppi says,Charmilles was the only one toaddress this eventuality. There is acut-out on the top of the machine soheavy blocks can be top-loaded witha crane.

“If you’re not a customer that’s liftingheavy loads and dropping bigblocks of material into the machinework area, you’re probably notgoing to see that as a big sellingpoint,” Racioppi says. “But if you’re aperson who is putting a 125-poundor 150-pound block of steel in andout of your machines, you can imagine the difficulty lifting it to waist-height and then pushing it ontoa conventional table. Not the type ofthing you want to do all day long sofor us that top-loading feature wasvery attractive.”

Speed is the next feature that makesthe Robofil 330F so attractive toVEKA. The 330’s tank fills and drainsvery quickly. This is important

of cutting complexextrusion tools. TheRobofil 330F is theonly wire EDM thatcuts a 30-degreetaper on 15.75” tallworkpieces – submerged. In addi-tion, the machinefeatures larger X-Y-Ztravels of 15.75” x11 .8” x 15.75” plus U-V travels of 19.68” x 15.75”.

Upper head travel has beenincreased on the Robofil 330F by 2”per side. This allows a workpiece tobe positioned very near the tablelimit of the primary X or Y-axis withfull taper cutting over a very largeworking area.

Racioppi says, “The heavy tapering isfantastic. Not only does it cut heavytaper but it trim-cuts consistently,yielding a uniform surface, whichreduces polishing time and gives you good surface quality on the

extrusion.

“The ability of the 330F to cut aheavy taper pretty much putthe nail in the coffin of all

the other manufacturers.We just couldn’t lookany further. It was point-less. Nobody else couldcompete againstCharmilles in heavytaper cutting.”

The Robofil 330F alsocomes equipped withIntegrated CollisionProtection (ICP). The ICPprevents damage to themachine if a workpiece

3New Ideas In EDM


Adam Reed, a wire-EDM apprentice at VEKA, downloads a program on the Robofil 330F

because VEKA works on very tallworkpieces. Racioppi says that thefill/drain cycle was the fastest of anymanufacturer he had seen. With thevolume VEKA puts through its wireEDM machines, the fill and draincycle time becomes very important.

Charmilles’ Nagle says the 330Fboasts better technology for cuttingtall parts than anybody else in theindustry.

“Most of our competitors,” Naglesays, “have to make extrusions insmaller pieces which creates a seamline. If you have a seam line it isanother area where plastic, when it isextruded, can get stuck and caught.The next thing you know the extrusionwill show a line through it or start tobuild up and you have to tear it allapart. So cutting taller parts withoutany seams to it is a big plus for theirtype of work.”

Last, but certainly not least, is theability of the 330F to cut heavytapers. A heavy taper isvery important inthe process

or clamping device, for example, is inthe path of the machine’s operation.This can prevent downtime andrepair expense.

Though VEKA has been in businesssince 1967, its loyalty to Charmillesbegan only in 1996 when the first330F was purchased, making it oneof the first such machines in NorthAmerica.

There is no question that VEKA plansto buy additional Charmillesmachines in the future.

“The other EDM suppliers have notaddressed the extrusion die makingmarket as thoroughly as Charmilles,”Racioppi says. “When you factor therigid work table, top-loading capa-bility, heavy taper cutting, andcollision protection, Charmillesclearly is superior in this market withthe 330F machine.”

Reed performs a part set-up on VEKA’sRobofil 330F

4

Brother Helps AcuCut Exceed Customer Demands


Speed, automation, dependability and cost add upto the success the Brother Model HS50A has helpedbring to AcuCut, Inc. of Southington, CT. With production orders in the aerospace and medicalfields rising in the last year, Mike Barmore, AcuCut’svice-president of production needed more equip-ment to meet his customer’s demands.

And Mike is increasingly turning to Charmilles/Brother to meet — and exceed — those customerdemands.

“We initially started with the Brother HS5100 with aB-axis,” Barmore said. “It took up very little floorspace and was extremely dependable. We wantedmore diversification so when the HS50A entered themarket we traded in the 5100 and purchased 3HS50A’s. We now have purchased seven in a year’sspan. You might say they speak for themselves.”

AcuCut was one of the country’s first job shops toutilize Wire EDM when Stephen Barmore founded it

with two employees in 1978. Business quicklyboomed and AcuCut was purchasing one to twowire machines each year to accommodate cus-tomers’ needs.

Innovation soon became part of the company’s lexi-con. The first laser cutting machine debuted in 1985to supplement the Wire EDM service. Two yearslater, CNC Sinker EDM and CNC Small Hole EDMDrilling were added. In 1996, AcuCut began to offergeneral machining as a complement to all of itsother services.

Today, there are 50 employees and annual salesrevenue is approximately $5 million.

AcuCut purchased their initial HS5100 in the fall of1998. Mike Barmore said the HS5100 was equal inspeed to the more expensive wires in the shop. “Itdid the job within budget and performed well,”Barmore said.

Mike Barmore, vice president of production at AcuCut, holds anaerospace part produced by the Brother HS50A.

A row of Brother HS50As at AcuCut in Southington,CT. The company has purchased seven HS50As in justone year.

What Barmore saw in the newBrother HS50A was critical toAcuCut’s needed diversificationstrategy. The new Brother offeredtaper with a programmable Z andmany new control features. Intotal, the Brother HS50A was acomplete package that was worththe investment.

The Brother EDM is critical toAcuCut which runs three shifts aday. Outstanding teamwork exemplified by careful planningand fixturing their production workproperly, has allowed AcuCut’sgrowth and expansion in all areasof EDM.

“Anytime you can keep the costdown, make consistently goodparts and meet deliveries, thework will continue to come,”Barmore said.

AcuCut continues to depend onCharmilles. AcuCut recently pur-chased two new Charmilles EDMSinkers, the Roboform 35 and theRoboform 55. “We keep growingwith the industry to guarantee thebest product on time for goodvalue,” Barmore said.

5New Ideas In EDM


An AcuCut employee uses the easy-to-operate control on the Brother HS50A.

Poor

Fair

Excellent

NewMach

ineO

wners

How Is Business NOW?

Good

Overall, business seems to begood if you judge by our mostrecent business forecast survey. Of those responding to the survey,61 percent said business wasgood to excellent. That’s animprovement over the last survey.

On this survey, AMBA requestedsome additional information tohelp me verify a trend I thought Iwas seeing in the industry: theshops with newer equipment tendto be busier and have a moreoptimistic outlook than shops witholder equipment.

For example, in the category question “How is businessNOW?” respondents who replied“Excellent” in that category haveequipment that averages 2 yearsold. In the “Good” category ofhow business is doing, 35 out of48 respondents have equipmentthat averages 3 years old. Onerespondent in the “Excellent” cate-gory has equipment 1 year old,and three respondents in the“Good” category have equipment1 year old.

Now for the “Fair” category ofbusiness, 16 respondents haveequipment averaging 4 years old.For those responding that businessis “Poor” or “Bad”, their equipmentaverages 6 years old. A fewresponded that their equipment is8-10 years old.

Judging from the information pro-vided in this survey, and from whatI see while traveling and visitingshops, I think my theory is correct.The newer the equipment a moldshop has, the more business ithas. Obviously, shops utilizingnewer technology are able to bemore competitive.

A respondent in the “Excellent”business category commented: “Wehave doubled ourwork force in thelast year.”

Though the bene-fits of new technology are obvious, makingthe investment is a tough decision.One moldmaker who’d recentlymade a quarter-million dollarinvestment in new equipment toldme that getting rid of older equip-ment that still runs perfectly is thetoughest thing he has to do. Iknow that feeling. I had a FujitsuDL3400 high-speed (by 1984 standards) dot matrix printer. For16 years this printer served mewell, printing out hundreds ofthousands of pages over that time,never missing a beat.

Recently, I got a new computersystem (my old one was 5 yearsold, a lifetime in computer time),and purchased a new, H-P

Deskjet printer. Although the oldprinter ran perfectly, I couldn’tdownload things off the Internetand I couldn’t print in color. It did-n’t stop me from doing my job, butit was a terrible inconvenience

and cost mea lot of timein hand-copyingthings off theInternet that I

needed when I do research.

As our survey indicates, things arepretty good out there. A lot isbeing done at the technology endto help mold shops improve theirproductivity. Taking advantage ofnew technology is paying off forthose shops that make the investment.

For more information on theAmerican Mold BuildersAssociation, please contact:

Annmarie Parisi

Membership ServicesCoordinator

630-980-7667

[email protected]

6

Editorial Comment on theBusiness Forecast SurveyBy Clare Goldsberry

Reprinted with permission of Clare Goldsberry and the American Mold Builders Association


The newer the equipment

… the more business …

8


How is business NOW?

Excellent 18%

Good 43%

Fair 27%

Poor 10%

Bad 2%

What is the average mean age of your machines?

Excellent 3.33 years old

Good 4.12 years old

Fair 4.54 years old

Poor 6 years old

Bad 6 years old

Projection for the next three months:

Increase substantially 5%

Increase moderately 37%

Remain the same 47%

Decease moderately 9%

Decrease substantially 2%

Fall 2000 Business Forecast Results(Compiled by the American Mold Builders Association)

Current level of business vs. 3 months ago:

Quoting

Up 32%

Same 41%

Down 27%

Shipment

Up 32%

Same 50%

Down 18%

Backlog

Up 34%

Same 32%

Down 34%

Current level of business vs. 3 months ago:

Profits

Up 25%

Same 45%

Down 30%

Employment

Up 25%

Same 58%

Down 17%

Current average work week:

Shop Hours: 49

Design Hours: 48

Current plant employment:

Shop Employees 21

Design Employees 4

Average number of hours perweek, per machine:

CNC EDM 71 hours

WIRE EDM 62 hours

Machining Center 73 hours

More or less than one year ago:

More 62%

Less 29%

Same 9%

Did you request the lead listingfrom NPE? Yes 53%

RFQ’s:

Yes 7%

Not yet 21%

No 69%

No response 3%

Why Not?

Can’t handle more work 7%

Wasn’t aware/forgot/send 27%

Not interested 20%

Too many 18%

No response 11%

Other 17%

The following AMBA BusinessForecast survey was developedto provide AMBA memberswith a projection of businessconditions in the upcomingmonths. The October 2000forecast survey resulted in a26% member response rate.The results disclosed the following:

Kaveh Vafaei is a man of theworld and he’s building a world-class business. Born in Iran, rearedin France, and educated inCanada, the 29-year-old Vafaei isone of four partners at SEKAMTechnologies based in Waterloo,Ontario. SEKAM specializes infine blanking production, a metalstamping process that utilizeshydraulic presses.

One of the keys to SEKAM’sexplosive growth has been theprowess of Charmilles’ Robofil6030 wire-EDM. Indeed, whenVafaei took delivery of the 6030 inOctober 1999, just one monthafter starting SEKAM, he becamethe first operator of the machine inCanada.

One of the first phone calls Vafaeimade was to Charmilles distribu-tor Darren Carroll, a vicepresident of Ossco Machine Salesin Newmarket, Ontario. The twomet for lunch and Vafaei quicklysteered the conversation towardswire EDMs and the machine he

wanted: the Robofil 4020. He hadused the Robofil 4020 extensivelyand liked the way it worked.

“One of the things that I likedabout the machine,” Vafaei saidof the 4020, “was that it was veryuser-friendly. The tank was veryaccessible. Everything was verysimple and obvious. It was the firstCharmilles machine that webought and our operators werevery happy with it.”

But Carroll had other ideas andcommunicated them to Vafaei. Hementioned a bigger machine, theRobofil 6020SI, as perhaps beingwhat Vafaei’s new businessneeded. Infact, Carrollsaid, therewas a brand-new modelcoming out,the Robofil6030SI, which was the new andimproved version of the Robofil6020SI.

Carroll said, “Being a start-upshop, he wanted to deliver to thecustomers in a timely fashion andbe right the first time. And some ofthe new features on the Robofil6030SI – with the threading andability to search for a hole – weregoing to lend themselves to whathe was trying to do. At the start,with only himself and one otherguy, he wanted to automatethings as much as possible.”

The Robofil 6030SI is the largest

machine in Charmilles’ 1030 seriesof wire-EDMs and Carroll felt thiswas an important feature forVafaei. “I think the larger machinegave him the ability to initiallytake on any work that came in,”Carroll said. “There was no workthat he had to turn down – hewas able to accommodate it all.”

And with the Robofil 6030SI,SEKAM was ready to hit theground running. “When theCharmilles’ technician was doneinstalling the machine,” Vafaeisaid, “it was ready to go. We did-n’t have to do any test cuts.”

The Robofil 6030SI has many

10

Charmilles’ Robofil 6030SI Fuels SEKAM’sExplosive Growth


The Robofil 6030SI has been a keyto SEKAM Technologies’ explosivegrowth.

qualities that make it perfect forSEKAM. Its surface integrity gener-ator leads to longer tool life.Moreover, it boasts high cuttingspeed for improved productivityand a faster threading cycle forimproved throughput.

SEKAM grew quickly. Vafaeistarted with three employees. A little over one year later, he had24. Vafaei and his partners areblowing by their revenue goals,too. Compared to the originalprojection of $2.6 million(Canadian), Vafaei expects thebusiness to earn $6 million.

One of the things that I likedabout the machine was that itwas very user-friendly.

“Every time I go out there,” Carrollsays, “he’s added more employ-ees, more presses, and he’s gotmore work going out the door. Hestarted in a small physical spaceand now it seems he’s alwaysknocking out a wall and takingover the unit next door. I musthave walked through four unitsyesterday that are now all hiswhere he knocked the wall outand expanded. He’s pretty muchtaken over the whole complex thathe’s in. It’s tremendous growth insuch a short time period.”

Most of SEKAM’s business is tiedto the auto industry. They are aTier II supplier, meaning that theyare supplying North America’s topauto suppliers such as MagnaInternational and the VentraGroup. SEKAM is also developingwhat Vafaei terms a “niche market,” and that is in the area of micro-electronics where thecompany makes mechanical support plates for computers. Thisis a growing segment of the com-pany’s business and an importantbuffer if the auto business slowsdown.

Through it all, the selection of theright wire-EDM was critical,according to Vafaei.

“If the wire EDM is done correctly,then the rest falls in place,” hesays. “We’re after very tight fits inthe die so the EDM has to be veryaccurate. That’s why we wentafter the Robofil series. These arethe only machines that can holdour tolerances. We need theirconsistency and their accuracy.”

Dimensional tolerances on wire-cut pieces must be kept toabout 2/10ths of a thousand,Vafaei says.

The Robofil 6030 has performedvery well for SEKAM. It runs 24hours a day, seven days a week.Much of that running time occursduring off-hours when SEKAM isclosed for the evening or theweekend. If theEDM operatorneeds to be called,a modem con-nected to themachine dials hispager.

Vafaei and his man-agement team arecurrently discussing

the purchase of anotherCharmilles wire-EDM machine.That of course is fine with Ossco’sCarroll. “We see ourselves as along-term partner with him. Weplan on being there for Kaveh, tooffer him the latest and greatestthat Charmilles has to offer that’sapplicable to his industry.”

11New Ideas In EDM


SEKAM’s Ricardo Joseph works on the Robofil 6030SI.

Ricardo Joseph, an EM Technician at SEKAM Technologies works on the controlof the Robofil 6030SI.

Charmilles Technologies haschanged its name to Charmilles.A host of changes accompanythe new corporate identity,including a creative new “We Push the Limits of EDM” ad campaign:

• New Charmilles logo

• New Solutions logo

• Chamilles calendar, new yearcard, and catalogues for newproducts

• Machine badging

• “We Push the Limits of EDM”ad campaign

12

What’s New


You Can See Your Ad in New Ideas In EDMCall Steph Meyers at DGS Group • 317-479-3155

The Charmilles Parts Catalog is now available on CD ROM.This disk contains valuable machine part photos and lists foryour Charmilles EDM Machine. If you have not received yourcopy in the mail, contact Charmilles Customer Support at 1-800-CTC-1EDM.

Charmilles Technologies recently revampedits web site, www.charmillesus.com, tobecome more customer-friendly. One of thebest examples of this new focus is the site’sability to interface with customers wishing to purchase, sell or trade a used Charmilles EDM.

“We wanted to be more customer-focused,”says Gisbert Ledvon, Charmilles’ marketingmanager. “We wanted not to just have a website with product information but to have aweb site with useful information for customerswhich would include a used machine tradesection.”

The web site itself lists the advantages ofpurchasing a used Charmilles EDM. The sys-tem allows buyers and sellers to list machines

that they would like to purchase or to sell. Thesoftware will then try to match buyer andseller in the U.S. – with no broker involvement.

Similarly, a trade or sale is enhancedthrough web site commerce at www.charmillesus.com/prod/used_edm.cfm.Since Charmilles finds the buyer, the sellershould realize a higher value without anequipment broker’s participation.

The site also allows for customization.Sellers can list the attributes of their currentmachines and buyers can list the qualitiesthey are seeking in a Charmilles wire or sinkermachine.

And there’s more to come. “Eventually we’llbuild a database that will allow us to matchup buyers and sellers,” Ledvon says.

13New Ideas In EDM


Revamped Charmilles Web Site Features Used Machine Section Used EDMs

Charmilles’ New Robofil 240 and 440

Support a Wide Variety of

Applications

With its “CT-Millennium” numerical control,Charmilles Technologies’ new Robofil240/440 are two of the world’smost versatile submerged wireEDM machines. Thesemachines, the product ofCharmilles’ many years ofexperience as an industryleader, support a wide varietyof stamping tools, moldmakingand mechanical engineeringapplications.

The new Windows NT-basedcontrol makes the machinemuch more user-friendly anddrastically shortens the learn-ing cycle. An easy-to-use touchscreen greatly facilitates andaccelerates operator input. Theoperator is guided by draw-ings, which illustrate theavailable options. Despite itsmodern and clean look, itremains very compatible withprevious Charmilles systemsand is easy to link to othercomputers and robots. Thecontrol also supports Ethernetcommunications.

The fixed table of the Robofil240/440 will support heavyloads as it’s made of thickstainless steel and rests directly

14


on a rhenocast main frame. The Robofil240/440 also come equipped with IntegratedCollision Protection (ICP). The ICP preventsdamage to the machine if a workpiece orclamping device, for example, is in the path ofthe machine’s operation. This can preventdowntime and repair expense.

Charmilles has developed a unique andexclusive process to widen the range of avail-able applications with the design ofsymmetrical XY and UV tables. These travelsare X (U) 13.77 x Y (V) 8.66 on the Robofil240 and X (U) 21 .65 x Y (V) 13.77 on theRobofil 440. A programmable Z-axis allowsseveral workpieces of varying heights to beworked on simultaneously without operatorintervention.

With more and more industrial sectors makinguse of wire EDM for machining tall work-pieces, the Robofil 240/440 deliver

continues on pages 16 & 17 …

Charmilles’Robofil240/440 aretwo of the twoof the world’smost versatilesubmersed wire-EDM machines

Charmilles Pushes the Limitswith GroundbreakingEDM’s at Open House

An enthusiastic audience of 300 cus-tomers, distributors, and journalistsglimpsed the exciting future of EDM atCharmilles Technologies Open House,held at the company’s North Americanheadquarters March 23-24, 2001 .

Titled ‘We Push the Limits of EDM,’ thenew product rollout was attended by Dr.Kurt E. Stirnemann, President and CEO ofAgie Charmilles Group.

The product presentation didn’t disap-point as Charmilles’ product managersunveiled a bevy of new products. “Ourexpectations were certainly met,” saidGisbert Ledvon, Charmilles’ marketingmanager. “Everybody was excited aboutthe new products. Customers wereastounded about the new products,especially the twin wire machine and theCharmilles Millennium Control.”

The unveiling of the revolutionary twinwire machine, the Robofil 2030SI-TW,was a highlight of the two-day event.Product manager Bill Boehmert did thehonors of presenting the details of thefirst wire EDM to feature a fully auto-mated dual-wire system. The PentiumPC-based control, featured on the newForm 20 ZNC machine, was presentedby the product manager, Eric Ostini. Thecontrol is simple to use because of thetouch-screen interface, the first of its kindin this class of machine. The only vari-ables that need to be entered into thesystem are the material to be cut, the surface finish desired, and the depth ofthe cut.

Ostini also presented the Robofil240/440, two of the world’s most versa-tile submerged wire EDM machines withthe new Millennium Control and a fastwire threading system. Damien Carron, aproduct manager from Geneva, offeredhis insight into the speedy Roboform 35P,

54P and 55P. All three models offerspeed enhancements when compared tocurrent models. The acceleration speedis two times as fast, the axis speed isthree times faster, and the pulsationspeed has doubled, too.

After the product launches, Charmilles’President Harry Moser facilitated a livelyquestion-and-answer period that wasmuch appreciated by distributors andcustomers.

Robofil 2030SI-TW Revolutionizes

Wire EDM with First Automatic Wire

Changer

Charmilles Technologies revolutionizes thewire EDM field with the world premiere of theRobofil 2030SI-TW (Twin Wire) ElectricalDischarge Machine. The Robofil 2030SI-TW isthe first wire EDM to feature a fully auto-mated dual-wire system. Now it is possible toperform a quick changeover without operatorintervention.

The productivity gains from this unattendedability are significant. Depending on theapplication, productivity can reduce machin-ing times from 30 to 50 percent because thelarge diameter wire can be used for pocket-ing in the rough cut and the small wire isapplied for small-radius finishing. Totalmachining time is reduced in this processwhich boosts productivity.

The Robofil 2030SI-TW does not require anyspecial technologies or programming.Installation of the two wires does not compli-cate the use of the machine since the set-up isautomatic for both. During machining, theRobofil 2030SI-TW automatically switches toanother wire as needed. This changeovertakes less than 45 seconds.

30 degrees of taper irrespective of Z position.The Robofil 240/440 achieve angles of 30degrees across the entire length of Z travelprogrammable from 0 to 8.66” (Robofil 240)and 0 to 15.75” (Robofil 440).

Another outstanding feature of the Robofil240/440 is their new, unique, and fast wirethreading system, which stretches the wireand cuts it under the effect of heat. A coolingair flow inside the tube allows it to accuratelycontrol the cutting point’s exact location. Thewire cutter is maintenance-free since it has noparts that are subject to wear. It leaves noburrs and a tapered wire tip makes it easy topass through the wire guides.

16


Approximately two years

ago, Charmilles

Technologies sent out a

mailing that we are

maintaining Andrews

parts inventory on a

non-restocking basis.

We still have most parts

in inventory, but since

these parts are being

maintained on a

“non-restocking” basis,

we would like to encour-

age you to contact us to

ensure availability. Please

contact our Customer

Service Center at

1-800-CTC-1EDM to place

your parts order today.

We hope you continue to

use your Andrews

machine for years to

come and will think

“Charmilles” for all of

your EDM needs.

Andrews Machine Parts

The revolutionary Robofil 2030SI-TW, thefirst-ever EDM that comes equipped with anautomatic wire changer.

Charmilles’ Form 20 ZNC Combines a

Manual Machine with a Pentium

(trademark of Intel) PC Control

Charmilles Technologies’ new Form 20 ZNCis the perfect marriage of a manual machinewith a touch-screen, Pentium PC-based control.

The control is simple to use because of thetouch-screen interface, the first of its kind inthis class of machine. The only variables thatneed to be entered into the system are thematerial to be cut, the surface finish desired,and the depth of the cut. From there, the con-trol automatically generates the program.

Because the control’s logic operates with theuse of graphics and icons, and not text, thelearning curve is very short. The Form 20ZNC’s international appeal should be greatas non-English speaking personnel can oper-ate the machine easily.

The control’s performance is very sophisti-cated. The control manages the optionalorbiter, which enables the machine to cutintricate parts. There is also the capability ofperforming measurement on the control,which will split the distance of two points inhalf so the operator can find the center of aworkpiece very easily.

The Form 20 ZNC has a Charmilles genera-tor, available in either 32 or optional 64amps with Microfin II, which gives great sur-face quality of RA 0.4 µ m and performance.Glass scales are present on all axes. TheForm 20 ZNC comes equipped with copper-to-steel, graphite-to-steel, and coppertungsten-to-carbide technology and has avery high pulsation speed of up to 1 .18inches/second, especially important for deeprib burns.

Charmilles Form 20 ZNC combines amanual machine with a Pentium control.

17New Ideas In EDM


Acceleration Speed Doubles on New

Roboform Series

Speed is the key for Charmilles Technologies’new generation of Roboform machines – theRoboform 35P, 54P, and 55P. All three modelsoffer speed enhancements when comparedto current models. The acceleration speed istwo times as fast, the axis speed is three timesfaster, and the pulsation speed has doubled,too.

See the Roboform 35PQCRi, and Robofil 240in action at Charmilles’ EASTEC booth #5345at the Eastern States Exposition Grounds inWest Springfield, Massachusetts.

The speed increase means greater productiv-ity. Because of the advancements inacceleration speed, tool change time is 35percent less than it used to be on theRoboform 35 or 55. There is also a 27 per-cent time savings for measuring cycles.

The Roboform 35P and 55P come equippedwith drop tanks. This enables the operatoreasy access to the machining table fromthree directions. The drop tank design alsoyields quicker fill-and-drain time. Time is alsosaved because the drop tank can be pro-grammed to match the height of theworkpiece.

Accuracy has not been sacrificed at theexpense of speed, however. All of themachines have glass scales for life-long accu-racy. The machines can also accommodatethe Quick Change Robot (QCRi) feature. TheQCRi allows operators to further boost theirtotal hours of EDM productivity because oneCNC controls both the robot and themachine.

All models come equipped with the SinkerProgramming System (SPS). This new offlinesystem allows the operator or mold designerto program complex diesinking applicationswith a few mouse clicks. SPS will also enablethe operator to utilize command programswidely used for the efficient automation ofRoboform diesinking machines.

Speed is the key for the new generation of Charmilles Technologies’Roboform machines – the Roboform35P, 54P, and 55P.

Plansee Tizit is an international company with over 75 years ofindustry experience in the production of carbide. The com-pany is headquartered in Reutte, Austria and employsapproximately 4,000 people worldwide. Plansee utilizes itsexperience and expertise in numerous collaborations withboth wire EDM machine producers and die builders, to assistin the improvement of wire EDM technology in the cutting oftungsten carbide.

With so many variables involved in the wire EDM process,general rules are difficult to establish. However, Plansee makesevery effort to inform customers of specific problems and mistakes that commonly occur in the industry. The followingare four problem areas with wire EDM that Plansee hasrepeatedly encountered:

• Surface Damage• Thermal Cracking• Electro-Chemical Reaction (Pitting)• Corrosion

Surface Damage

Generally, the examination of any wire EDM roughed, or pre-cut, surface will display three zones. The rough cut that isgenerally accompanied by the highest electrical power andfeed rate, creates a white zone which comprises a mixture ofresidue from different materials. Most of the residue, or recastlayer, comes from melted material from the work-piece andthe wire. This is Zone 1, and it is approximately 3 – 5 µmdeep.

The heat-affected area, immediately beneath the white zone,is Zone 2. The same high power/high feed conditiondescribed above creates thermal disturbances (approximately27,030° F) generally about 9 µm deep. However, many exami-nations of customer-supplied specimens over the past fewyears have shown damage that goes much deeper than 9µm. This is a serious problem, because if this cobalt-depletedregion is not fully removed by finish passes on the wiremachine, the results in the die will be disastrous.

Zone 3 (figure 1) is the undamaged carbide area that must bereached through sufficient re-cutting if the important mechani-cal properties of tungsten carbide are to be seen. It isabsolutely essential that this zone be reached. The number ofpasses it takes to accomplish this is gained by experience inwire EDM, but each employee involved should be fully awareof the (Zone 1 and 2) condition and the need to remove it.Figure 2 clearly illustrates the situation that all die makers must

be aware of. They also must know that good surfaces result inlonger tool life; but good surfaces cost money to achieve.

Thermal Cracking

Thermal cracking and cobalt depletion occur because thehigh power of the generator can create very high tempera-tures that the surrounding carbide cannot adequately transferaway from the work area. The problem is compounded by thehigh feed rates and poor electrolyte flushing, combined with acorresponding increase in the dielectric conductivity. Whenthermal cracking occurs, the user frequently says there issomething wrong with the carbide’s quality. (See figure 3 for adescription)

Spark erosion machines, sometimes called “drill devils”, arefrequently used to quickly “shoot” holes in carbide blocks.Blasting, shooting, and devil are good words to describe thisprocess in carbide. Thermal cracks and chips up to a depth of0.02” are the results of too much power, too much feed, andpoor flushing. Judging by the number of failures Plansee hasseen, they recommend reduced power and the allowance ofat least 0.01” between the start hole and a finished surfaceposition.

Electro-Chemical Reaction & Corrosion

The topics of electrochemical reaction (pitting) and corrosionmust be considered together, since both reactions occur simul-taneously on both eroded and non-eroded surfaces. Theseeffects become evident on the entire workpiece, not just thewire-cut surfaces. The spots, or small holes, that appear on thesurfaces, are called pitting. Often, it is not possible to see thepits (actually cobalt depletion) during the first stages.However, they become very evident as the machining or pol-ishing of the workpiece continues, or even worse, during theblanking application. (Figure 4 shows typical pitting, which isvisible to the unaided eye)

As described above, the pits will appear on non-machinedsurfaces as well. This is because the cobalt binder that literallyholds the tungsten carbide together is magnetic. Therefore, themagnetic cobalt draws particulate matter to itself from thedielectric, which results in mechanical wear and increasedcorrosion.

Some mechanical wear actually occurs the instant the wirepasses a given area, due to the energy of the spark and theoscillation of the residues that it causes. The pitting of the

18

W-EDM of Carbide from the View of a Metallu


fig. 3fig. 2fig. 1

binder is due to an electrochemical process that is takingplace in the dielectric, which affects the surfaces to a depth ofapproximately 20 µm. This process occurs to a far greaterdegree if flushing is poor and/ or the conductivity of thedielectric is too high. It is important for a Wire EDM to controlthe water conductivity and warn if the level is exceeding thepre-set value. (Figure 5 shows a cross section of the effects ofpitting)

Every toolmaker would like to put a large carbide block on hiswire EDM machine on Friday afternoon, do the programmingand take out 30 or more ready to use die inserts on Mondaymorning. But chemical corrosion has been setting up barriersto this practice. Parts produced over the weekend or someother extended period often did not meet a customer’srequirements due to poor wear characteristics, chipping, andpoor surface finish (pitting) on die parts.

The composition of carbide contributes to the aforementionedproblems. Carbide consists of tungsten carbide and cobalt.Cobalt is used as the binder and provides fracture toughnessto the modern carbides. From the electrochemical view, cobaltbelongs to the non-noble metals. Due to the contact with thedielectric (water H2O with high (H+) ion concentration) youget electrochemical corrosion in the form of pitting. Corrosionin this case the binder (Co) is dissolved.

Therefore, it would be ideal to choose wire EDM carbidegrades which resist corrosion by using binders with noblealloys. Cobalt could be replaced, for example, by Nickel. Thatwould eliminate the corrosion problem. However, it is not wireEDM that assures good tool performance — it is the mechani-cal properties of the carbide grade used. Because of theoutstanding wettability that exists between cobalt and tung-sten carbide, there is no better solution with regard tomechanical properties.

Plansee Tizit has announced a new carbide grade for the tooland die industry. Plansee has achieved mechanical propertiesidentical to traditional grades, but with better susceptibility tocorrosion and an improvement in corrosion velocity of 80 –100 times.

With traditional carbide grades you see signs of corrosionappearing on tungsten carbide after approximately 8 hours indielectric. According to theoretical measurements in their lab-oratory, Plansee predicted that the onset of corrosion couldbe delayed up to 800 hours.

In order to achieve high performance surfaces, there are several important factors that must be carefully considered:

• temperature affected zone• conductivity of the dielectric• flushing• water change• water quality: pH-value, chlorine content, etc.

After designing an electromechanical corrosion test for thisspecial application in Wire EDM machines, the potentiody-namic current density potential curves in an aggressivelycorrosive medium (dielectric pH<5) were recorded. In comparison to the known corrosion tests, (loss of weight usinga corrosion medium according to DIN 50905), this new testmethod for carbide indicates the process by which carbidecorrodes.

In this test the carbide test piece is immersed in an aggressivemedium and an electrical potential is charged. The electricalpotential is continuously increased and the current is measured. The measured current is a good indicator of theamount of cobalt that has been dissolved and how quickly thecorrosion is advancing or the corrosion velocity. The electricalpotential curve relates to the corrosion susceptibility or proba-bility of the material. (In figure 6 the measured current densitycurve is shown for standard carbide and for the newly devel-oped patent pending grade from Plansee TIZIT).

Because of the self-developing protecting layer which is continuously formed (with the CF-grade) just before Cobalt is dissolved, the corrosion velocity can be decreased by afactor of 80 – 100. The protecting layer consists of chromium-oxide and cobalt, which can be seen in a transmittingelectron microscope. (See figure 7) In addition, the cobaltbinder was modified with Rhenium to reduce the tendency tocorrode.

By using the right carbide and a wire EDM machine that controls water conductivity and incorporates sophisticatedcarbide technology like the Robofil series, no grinding is nec-essary to produce carbide dies and punches with excellentsurface integrity.

If you would like more information on wire EDMs, feel free tocontact a Charmilles representative. For further informationabout carbide, a Plansee Tizit representative would bepleased to assist you.

19New Ideas In EDM


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fig. 4 fig. 5 fig. 6 fig. 7

GEORG FISCHER Manufacturing TechnologyGF

560 Bond St.Lincolnshire, IL 60069


Tel: (888) CTC 1EDM

AGIE CHARMILLES Group

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