Elk Grove Village, IL(847) 364-9060Allendale, NJ(201) 818-0100 Fountain Valley, CA(714) 434-6224The World Leader in CNC Swiss TurningThe Evolution Continues.Same quality youve come to expect with more tools, more exibility, more value.2-YEAR Machine andControl Limited Warrantywww.marucit.comCincom Sliding Headstock Type Automatic CNC LatheMachine specifcationsMaximum machining diameter (D) 20 mm (.79")Maximum machining length (L) 200 mm (7.87") / 1 chuckingMain spindle speed 10,000 rpmBack spindle speed 8,000 rpmLive tools 13 (standard)Supported by MCCs legendary, full service, distributor network.Experience the difference.Columns & Departments micromanufacturing.com|1Smartphone BeneftsYou can now use your smartphoneand a free application avail-able at get.neoreader.comto scan the quick response (QR) matrix bar code images below and instantly access the respective reports on our Web site, or enter the URLs into your Web browser.MicromachiningWatch a 3-minute video of a microlaser platform developed at Finlands Tampere University of Technology. The platform accepts several different lasers and has a single-axis velocity of up to 2,400mm/sec. with acceleration up to 2g.micro.delivr.com/141ui3-D laser systemSlovenian researchers recently demon-strated full 3-D tunable lasing in laser dye-doped cholesteric liquid-crystal microdro-plets from 15m to 50m in diameter. A brief video shows the process in action.micro.delivr.com/141ufSprue separatorALBA Enterprises offers a quick video demonstration of its sprue separator, which is said to address a common problem among micro-injection moldersseparating the runners from the good parts.micro.delivr.com/141u9On MICROmanufacturing.comCOLUMNS4Front PageDon Nelson,PublisherManufacturing shows signsof life.12Measurement MattersSusan Woods, Contributing EditorStrain gages for measuring and testing microparts.14MicromachiningAlan Richter, Senior EditorSpindle developments for micromachining.16Laser PointsRonald D. Schaeffer, PhotoMachining Inc.Using gas to improve laser machining.19Down SizingDennis Spaeth, Electronic Media EditorMEMS microphones.48Last WordDr. Alissa Fitzgerald, A.M. Fitzgerald &Associates LLCMachinist heritage key to MEMS future.DEPARTMENTS6 Tech News46 Products/Services47 Advertisers Index486Features www.micromanufacturing.com Main Offce40 Skokie Blvd., Ste. 450Northbrook, IL 60062(847) 714-0048micromanufacturing@jwr.comStaffPublisherDon Nelson(847) 714-0173dnelson@jwr.comEditorial DirectorAlan Rooks(847) 714-0174 arooks@jwr.comSenior EditorsJim Destefani(734) 528-9717jimd@jwr.comElectronic Media EditorDennis Spaeth(847) 714-0176dspaeth@jwr.comContributing EditorsBill Kennedy(724) 537-6182 billk@jwr.comAd Production ManagerJulie Disteneld(847) 714-0179 julied@jwr.comArt DirectorGina Moore(847) 714-0178 ginam@jwr.comAdministrative AssistantPat Jonespatj@jwr.comCirculationSynergy Direct Inc. (866) 207-1448andrea@sdicirc.comAdvertising SalesScott Beller (North/Southeast)(847) 714-0183scottb@jwr.comBarry Cohen (Central/South)(847) 714-0186bcohen@jwr.comPatrick Keefe (Central/West)(847) 714-0185pkeefe@jwr.comJody Nelson (International)(847) 714-0170jodyn@jwr.comSusan Woodssusanw@jwr.comAlan Richter(847) 714-0175 alanr@jwr.comJanuary/February 2011 Volume 4 Issue 12|JANUARY/FEBRUARY 2011|MICROmanufacturingCover Story22Implant NationWilliam Leventon,Contributing EditorImplantable medical-device market growth aided bymicroparts.28Swiss-Style SuccessGlen Crews,Marubeni-Citizen Cincom,and Bill Kennedy, Contributing EditorTools, tactics and tips for productive Swiss-stylemicromachining.33Rotary BurnAlan Richter, Senior EditorA rotary axis turns a wire EDM into a lathe.38Spinning TaleDr. LaRoux K. GillespieElectrospun bers exhibitincredible strength.ON THE COVER:Cover design by Tom Wright.382233FFFFFFFFFFFFFFFFFFFFFFFFFFRRRRRRRRRRRRRRRRRRRRRRRRRROOOOOOOOOOOOOOOOOOOOOOOOOONNNNNNNNNNNNNNNNNNNNNNNNNNTTTTTTTTTTTTTTTTTTTTTTTTTTpageDon NelsonPublisherManufacturing stinks. Ive heard that blunt assessment of the U.S. indus-trial sector plenty of times over the past 3 years. To all those whove uttered those wordsor even blunter appraisalsI oer a small measure of comfort: Manufacturing stinks less now than it has in a long time.Te latest government and industry statis-tics show: New orders rose 0.7 percent in November 2010, the fourth increase in 5 months. (Excluding the transportation sector, new orders grew 2.4 percent.)Shipments climbed 0.8 percent in November, the third consecutive monthly increase.Te December 2010 Purchasing Managers Index registered 57 percent, a 0.4 percent rise and the 17th straight month above 50 percent. (Fifty percent is the boundary line separating an expanding economy from a contracting one.)Plant capacity reached 71 percent in the third quarter of 2010, up 2.3 percent over the second quarter and 5.5 percent higher than the same period in 2009.Manufacturing jobs inched up 1.2 percent in 2010to roughly 11.7 millionthe rst increase since 1997. In a recent article in Te Wall Street Journal, economists predicted that the U.S. would add approximately 330,000 manufac-turing jobs in 2011. Tat certainly wouldn't come close to osetting the 6 million jobs lost since 1997, but it could indicate the bleeding has been staunched.Most of the manufacturing jobs lost the past 15 years wont be coming back. Tis is due to aggressive oshoring of production by American companies and to technolog-ical advancements that have signicantly raised U.S. workers productivity. From 1997 through 2009, factory productivity rose 54 percent, according to the Bureau of Labor Statistics. Another factor limiting U.S. job growth is the changing nature of manufacturing itself. Twenty years ago, we were looking at big companies that carried on almost all of their activities within their own four walls, said Massachusetts Institute of Technology Prof. Suzanne Berger during a recent inter-view on National Public Radio. Everything from research and development to design to production and on through distribution. Whats happened is that production does not take place within the four walls of a single company anymore. Te world of production has been completely broken up into indepen-dent companies. Engineers and technicians can be located thousands of miles apart.Tis has led to the formation of manufac-turing rms that have never manufactured anything. Tey design and prototype prod-ucts, then outsource production to other companies.MITs Industrial Performance Centera research group dedicated to the study of manufacturing innovation, productivity and competitivenessis looking at how the disconnect between design and production will aect U.S. manufacturing in the future. Specically, the group wants to examine the impact of losing the wealth of design inno-vations that occur during the manufacturing process. I think as we look [at] new technologies, said Berger, author of How We Compete and co-author of Made In America, were going to see a lot of areas where keeping manufac-turing closer to R&D and to design is going to be essential if we want to produce good products. Keeping production nearby would also be good for the U.S. economy in a multitude of ways, including the creation of well-payingand much-neededjobs.PublisherMICROmanufacturingTelephone: (847) 714-0173E-mail: dnelson@jwr.comFresh winds blowing through manufacturing4|JANUARY/FEBRUARY 2011|MICROmanufacturing6|JANUARY/FEBRUARY 2011|MICROmanufacturingTTTTTTTTTTTTTTTTTTTTTTTTTTEEEEEEEEEEEEEEEEEEEEEEEEEECCCCCCCCCCCCCCCCCCCCCCCCCCHHHHHHHHHHHHHHHHHHHHHHHHHHnewsHorizontal nanowire growth process yields nanoLEDsWhilereninganovelmethodfor makingnanoscalewires,chemistsat theNationalInstituteofStandardsand Technology(NIST)discoveredabo-nusnanowires that produce light sim-ilartothatfromlight-emittingdiodes. TesenanoLEDsmaysomedayhave their light-emission abilities put to work in microdevices such as nanogenerators or lab-on-a-chip systems.Typically,zinc-oxidenanowiresare grownverticallybychemicalvaporde-positionofmoleculesfromagasonto abasematerial.NISTchemistsBabak NikoobakhtandAndrewHerzingde-veloped a surface-directed method for growing zinc-oxide nanowires horizon-tallyacrossagallium-nitridesubstrate. Te technique uses gold heated to 900 C to catalyze crystal formation.Te scientists discovered that a cata-lystthicknessofabout20nmproduced nanowires that grew a shark-like dorsal n (referred to as a nanowall) with an electron-rich zinc-oxide portion and an electron-poorgallium-nitrideportion. Teinterfacebetweenthesetwomate-rialsknown as a p-n heterojunctionallowselectronstoowacrossitwhen charged with electricity. Te movement oftheelectronsproducedlightandled theresearcherstodubthestructurea nanoLED. AccordingtotheNISTscientists, the horizontal-growth method makes it easy to locate individual heterojunctions onthesurface.Microscopicexamina-tion of the nanostructures also revealed fewstructuraldefectsanddistinctp-n heterojunctions in the nanowalls.Teresearchersareusingthepro-cesstogrowzinc-oxidenanowireson dierentsubstrates,includingsapphire. Sapphire,byitsnature,isnotelectri-callyconductive,saidNikoobakht.So wegrowzinc-oxidewiresonit,then overcoatthewireswithGroupII-VI semiconductormaterialssuchaszinc sulde,cadmiumsuldeandcadmium selenide.Teideaistoallowtuningof thewavelengthofthenanoLEDemis-sions to cover a broader spectrum from theUVregiontonear-IRwavelengths, he explained.Te researchers hope nanoLEDs will leadtodevelopmentofhigh-e ciency solar cells, light sources and detectors. Jim DestefaniBook covers microfuidicsfabrication techniquesSelectionofthecorrectfabrication method is a key to producing microu-idicdevicesthatmeetdesiredapplica-tionrequirements,accordingtoJohn LeeandNarayanSundararajan,theco-authors of a new book called Microfab-rication for Microuidics.Teapplicationisimportantit driveseverything,saidLee,associate professorofMechanical&Aerospace Engineering, San Jose (Calif.) State Uni-versity.Butasfaraswhichfabrication process youre going to use, selection is oftenmoreimmediatelyinuencedby thelower-levelfunctionsyouwishto perform.Tebookcategorizesdiverse andnumerousmicrouidicfunc-tionsunderthreemainheadings: ow control within enclosed cavi-tiesandconduits,manipulation ofparticlesandcells,andejection of uids in the form of droplets or sprays.Teintendedfunctioninu-encesthegeometryrequiredin amicrouidicdevice,Leeex-plained.Forexample,foruid ejection,averycommongeomet-ric feature would be an orice per-pendiculartoaplanarsurfacefor adropletgenerator.Strategiesfor fabricatingsuchanoricemaybe quite dierent from approaches to makingapatternofconduitsthat lie within a plane for microchannel separations. So the function inu-encestherequiredgeometryand properties,which,inturn,dictate the fabrication processes and best-suited materials.Medicaldiagnosticsandrelated biologicalapplicationsformicro-uidicsreceivethegreatestattention in the book. Other applications include pollution-controldevicesthatallow rapid,on-siteanalysisofcontaminants and toxins, and microuidic devices that help control fuel cells, Lee said. Potential growthareasincludefabricationofmi-crouidics from multifunctional materi-als,suchaselectroactivepolymersand chemo-responsive materials, he added.J. DestefaniFabricating under the microscopeMicromanufacturerstypicallyuse microscopes for post-production evalu-ationandinspectionofparts,butone companyhasdevelopedasystemthat makes a microscope part of the produc-tion process. Teem Photonics 3-D Micro Fabrica-tion Module incorporates a nanosecond Nd:YAGlaser(1,064nmor532nm,up to40kHz,0.5ns)attachedtoamicro-scope. Te system relies on two-photon polymerization to fabricate parts.NISTIllustration at top shows a single row of nanowires (cylinders with red tops) with fin-shaped nanowalls extending outward. Optical micrograph above shows rows of nanoLEDs emitting light. micromanufacturing.com|9TTTTTTTTTTTTTTTTTTTTTTTTTTTEEEEEEEEEEEEEEEEEEEEEEEEEEECCCCCCCCCCCCCCCCCCCCCCCCCCCHHHHHHHHHHHHHHHHHHHHHHHHHHHnewsInTPP,ultrashortlaserpulsesselec-tivelypolymerizeanegativephotosen-sitivematerial,orselectivelybreakthe polymer chain in a positive photosensi-tive material. Molecules of the material absorbonlytwophotonsoflaserlight, hencethename.(Tolearnmoreabout TPP,seetheJuly/August2010cover story in MICROmanufacturing at www.micromanufacturing.com.)TeTeemPhotonicssystemwasde-signed to fabricate part features as small as 2m, with 200nm resolution, though ithasproduced1mfeatureswith 100nmresolution.Tesmallestfeature producedtodateis20nm.Typicalfea-turesincludepillars2mindiameter and30mhigh,andslots20mdeep and as narrow as 2m.Te3-DMicroFabricationModule combinesthreeelements:TeemPho-tonicsgreenQ-switchednanosecond laser, a piezoelectric sample-positioning stage with nanoscale accuracy, and pro-prietary Simpoly fabrication software.Temodulehasaworkenvelopeof 100m 100m 100m. An optional system is available that enlarges the en-velopeto300m300m300m. Userswatchtheprocessviaacamera, which is part of the system.Te module accepts 3-D scan les or CADles(SolidWorksorAutoCAD, forexample).Tesystems software develops the laser path and controls the slic-ing that creates a product, layer by layer. Te user de-neslaseroutputpower, time per part and the speed ofthesampleasitmoves pastthelasersfocalpoint. Tesoftwareallowsusers toproduceoneormore parts per cycle.Te3-DMicroFabrica-tion Module costs $50,000. AccordingtoDenisBar-bier,TeemPhotonicschieftechnology o cer, it takes a day to install the equip-ment and software and train users. Tesystemrequiresamicroscope, whichcanbepurchasedindependently or as part of the system. Te cost of an appropriatemicroscopeisestimatedat $20,000,bringingthetotalsystemcost to$70,000.Anybrandofmicroscope (716) 873-9907 www.titantoolsupply.comGrinding PinsDiamond and BorazonGrinding & Bottoming PinsGrinding WheelsDiamond and BorazonGrinding & Mounted WheelsDiamond FilesNeedle, Riffle, MiniatureSwiss Needle Files50% discount clearance salePolishing ProductsHand Stones; Diamond & BorazonSheets, Paste & CompoundRout-A-Burrs & ScrapersLarge Selection ofBlades and HandlesServing Your Needs for Quality Finishing Tools Since 1952Micro Finishing Toolsfor the metalworking professionalHuge 2010SALEPrices reducedup to 50%Teem PhotonicsThe Teem Photonics 3-D Micro Fabrication Module.10|JANUARY/FEBRUARY 2011|MICROmanufacturingTTTTTTTTTTTTTTTTTTTTTTTTTTEEEEEEEEEEEEEEEEEEEEEEEEEECCCCCCCCCCCCCCCCCCCCCCCCCCHHHHHHHHHHHHHHHHHHHHHHHHHHnewscanbeused,provideditisaninverted microscope with a 100-percent port se-lector, for eye safety. Teem Photonics of-fers the Olympus IX51 microscope with its system.Te3-DMicroFabricationModule canbeusedtoproducemicrouidic andMEMSdevices,microelectronics andnanophotonics.Plus,TPPhasthe potential to make negative-index optical devices.Biologicalapplicationsinclude theproductionofprotein-based,arti-cial,extracellularmatricesandbioassay chips. Te process has also been proven eective in microencapsulation and the productionofmicrocantilevers,pho-toniccrystals,microneedlearraysand prototype micromolds.Productshavebeenmadefromma-terialssuchassilver,aluminum,gold, tungsten,copper,ceramics,indiumtin oxide,acrylics,polyethylene,epoxies, Ormosil(aphotopolymer)andzirco-nium sol-gel. (Te metals are combined withresinsinvariouswaysorusedto coatacompletedpolymerizedstruc-ture.)Photosensitivematerialscanbe added to many polymers to make them more sensitive to the lasers UV light.Dr. LaRoux K. GillespieEditorsNote:Formoreinformation, contactDenisBarbier,TeemPhotonics, Meylan, France. Telephone: 011 33 476-040506.Web:www.teemphotonics.com. IntheU.S.,contact:JacquesBourgoin, directorofsales,Americas,TeemPho-tonics, Milipitas, Calif. Telephone: (408) 935-8390.Lights, camera, micro!Micromanufacturingrequiresspe-ciallightingconsiderations.Measuring dimensionstypicallycallsfordierent lighting than checking for stains, dust or surface-nish quality. (Detecting solvent stainsmayrequiredark-eldmicrosco-py, which excludes the unscattered light beam from the image.) Diuse light re-duceseyestrain,butitalsoreducesthe ability to see defects, such as burrs and texture dierences.Teequivalentofcleanroomlight-ingshouldbethegoalformostmicro-manufacturing operations, according to Paul Varni, president of American Clean Rooms,RanchoSantaMargarita,Calif. (Tecompanysmodularcleanrooms areilluminatedwith75foot-candlesof light; the light in an average o ce is 50 foot-candles.)Detecting burrs requires a strong light thatcastsshadows,butthelightmust be positioned so it does not reect into the technicians eyes. Incident angles of incominglightalsoaecttheabilityto readmarkingsandcapturethemwith cameras. Te optimal incident angle de-pends on surface roughness and the de-greeofshininessandtransparency.For example,wheninspectingintegrated circuits, an incident angle of 75 is best forhigh-surface-roughnessparts;for metalswithmoderateroughness,60 isrecommended.Ifthebackgroundis white, using lights at both 15 and 60 is recommended.Teideallightingarrangementfor microworkistwoormoreillumina-tionsourcesthatprovidediuselight formuchofthework,butallowthe usertocastshadowswhenandwhere needed.Smalluorescentandincan-descent units for workbenches are avail-ablewithexibleheads.Whenusinga microscope,side-positionedincandes-centlights,combinedwithuorescent sales@tungstentoolworks.comNow with Diamond, TiB2, HSN2, & more coatings online.FASTDELIVERY!Lighting issue Preferred solutionDetect stains UV light, dark eld microscopyDetect burrs Lights that cast shadowsDetect surface texture changes Lights that cast shadowsDisinfect surfaces UV lightMeasure SiO2 lm thickness Fluorescent lightCount parts Fluorescent lightReduce eye fatigue Fluorescent light, LEDsDeep microholes Through-the-microscope lens lightingGlare Change direction and magnitude of light micromanufacturing.com|11ringlightslocatedaroundthebottom ofamicroscopelens,provideanideal lighting setup. LED ring lights that pro-vide up to 1,900 foot-candles of light are available.Gooseneckber-opticilluminators providingupto40,000foot-candlesof light provide visibility in any hole. Ring-lighted4magnifyingglasses(about 130 foot-candles) are also good choices for the upper size limit of micro work.Someapplicationsrequirebottom lighting rather than side or top lighting. Microscopesthatincorporatecoaxial, through-the-lens light sources direct the light right where the eye is looking and are ideal for small, deep holes.L. GillespieLab brings metrology, micromachining R&D to LithuaniaAltechna Co. Ltd., a Lithuanian laser technologycompanyfoundedin1996, recently tripled the size of its laboratory facilitiesforR&Dandmetrology.Te Vilnius-basedcompany,whichfocuses on photonics and laser research, manu-facturesdiode-pumpedlasersources and components, develops laser micro-fabrication applications and designs op-tomechanical assemblies.TenewmetrologylabatAltechnas R&D division, called Workshop of Pho-tonics,performsQConopticalcom-ponentsandevaluateslasermicroma-chining results, according to R&D Sales ArchitectEvaldasPabreza.Halfofour companyisdevotedtoproductionof optics, laser crystals and similar things, so its very important to ensure the qual-ity of these components, Pabreza said.FinancedbytheLithuaniangovern-ment and the European Union, the new WorkshopofPhotonicslabmeasures opticalsurfacequality;transmittance andreectance;surfaceatnessand wavefrontdistortionofatandspheri-cal optics; the angles of prisms, wedges and other optics; and noncontact radius ofcurvatureandfocal-lengthmeasure-ments, according to Pabreza.Tefacilitiesalsoincludetwolabs equippedwithfemtosecondlasersand a laser assembly lab, all with cleanroom facilities.TeWorkshopsresearchers workwiththeircounterpartsatcorpo-rateandacademicpartnerstodevelop newsmall-scalelaserproductionpro-cesses.Researchpartnersincludethe LaserResearchCenteratVilniusUni-versity;LithuaniasPanevioMecha-tronikos Centras; Swinburne University ofTechnology,Melbourne,Australia; and Japans Laser Systems Inc.Formoreinformation,call+370-5-2725-738orvisitwww.wophotonics.com.J. DestefaniMikron Corp. MonroeTel. 203 261 3100Email: mmo@mikron.comwww.mikron.com/tool-usIntroducing the NEW CrazyDrill Cool XL family with through tool internal cooling fordeep hole drilling up to 40 x d, starting from .039"By using Mikron Tools, pecking is minimized.We open a new chapter when it comes todeep hole drilling. Example: drilling 40 x dinto challenging materials!Mikron helps you meet your micro- to medium-sized cutting tool needs with drills and mills insizes from .004 to .2362.Mikron has products to facilitate all of yourprecision tooling needs our CrazyDrill line isoutstanding for high-volume production.For low- to mid-size production lots the MiquDrillline is very cost effective. For high-speed-milling,we offer a top quality end mill line.Mikron is the one stop source for micro/smallcarbide cutting tools. Want to learn more?Please visit our website.12|JANUARY/FEBRUARY 2011|MICROmanufacturingMMMMMMMMMMMMMMMMMMMMMMMMMMEEEEEEEEEEEEEEEEEEEEEEEEEEAAAAAAAAAAAAAAAAAAAAAAAAAASSSSSSSSSSSSSSSSSSSSSSSSSSUUUUUUUUUUUUUUUUUUUUUUUUUURRRRRRRRRRRRRRRRRRRRRRRRRREEEEEEEEEEEEEEEEEEEEEEEEEEMMMMMMMMMMMMMMMMMMMMMMMMMMEEEEEEEEEEEEEEEEEEEEEEEEEENNNNNNNNNNNNNNNNNNNNNNNNNNTTTTTTTTTTTTTTTTTTTTTTTTTT mattersStrain gages were invented 70 years ago and have been used for years in products such as pressure sensors. Today, the gages are found in everything from small medical devices to aircraft components to bridge structures.Te electrical resistance of strain gages changes as the strain, or force, applied to them varies. Calculating that change provides the gages measurement capability. Te main application areas for strain gages are experimental stress analysis for R&D and manufacturing transducers for end products. Transducers, or sensors, include pressure sensors, load cells (a transducer used to measure forces) and torque sensors.Straintensile and compressiveis defor-mation of material that occurs on the surface of an object. Conventional strain gages consist of an insulating exible backing that supports a metallic-foil grid. Produced by photoetching a pattern into the foil, the grid determines the electrical resistance of the strain gage. Te more gridlines, the higher the resistance, according to Dirk Eberlein, product and application manager at HBM Inc., Marlborough, Mass.Te foil is bonded (glued) to an insulating polymer backing material. Tis carrier is then attached with an adhesive to the surface of the object under stress. As the object is stressed, the foil is deformed, causing its electrical resistance to change. Other gage components include a coating to protect against external eects, such as humidity or mechanical damage, and lead wires.Most strain gages are smaller than a postage stamp (9mm 12mm), but they can be much smaller. Typical strain gages are 6mm 5 mm (for uniaxial strain gages with a 3mm grid length) or 13mm 6mm (for uniaxial strain gages with a 6mm grid length). Uniaxial means the strain is measured in one direction. Measured in ohms, resistance is converted to millivolt output via a Wheatstone bridge (a divided bridge circuit used to measure elec-trical resistance). Te strain taking place is measured by applying a gage factor, which is the ratio of relative change in electrical resis-tance to the mechanical strain.Te information is transferred to a data-acquisition device. Te data is used for control and to warn when too much force is being applied, said Bill Richards, vice president of sales and marketing at Strain Measurement Devices Inc., Wallingford, Conn. For instance, a sensor can be put in a robotic hand and when the hand touches something, it tells the controller how hard that robot hand is touching [the object]or even if it is touching it.For stress analysis on larger structures, hundreds or thousands of tiny gages are applied. Aircraft manufacturers, for example, install thousands of strain gages on the body and wings to measure strain and, from that measurement, recalculate the mechanical stress, said Eberlein.Micro strain gagesManufacturers oer a variety of strain gages for micro applications.HBM, for example, has developed a strain gage with a foil-grid size of 0.3mm 0.9mm. Te carrier size of 2mm 1.2 mm also is not typical for a foil strain gage, said Eberlein. Our aim was to get 120-ohm performance in the smallest grid size possible.Designed for stress analysis, HBMs micro strain gage can be used in R&D, When showing strain is a good thingThree types of standard strain gages: uniaxial (bottom right), biaxial (top right) and a so-called chain with 10 grids on one carrier (left).HBM micromanufacturing.com|13such as testing mechanical stress inside of electronic parts directly on a printed circuit board. One of HBMs German customers installed a micro strain gage on a fully equipped PCB to determine how handling aected the board after it was manufactured. Other applications include measuring strain in notches and bore holes as small as 2mm, as well as between rivets found on aircraft.Strain Measurement Devices has used a thin-lm-vacuum-deposition process to bond strain gages directly to various metal substrates for 20 years. Tese gages are used in transducers to measure force.A thin-lmstrain gage eliminates the need for adhesive bonding to the product being measured. Instead, insulation is deposited onto the stressed metal surface to insulate the circuit from the metal substrate, said Richards. Ten, a thin lm of resistive alloy is sputtered over the dielectric layer in a vacuum chamber. Te lm is taken out and laser-trimmed to produce the four resistors of the Wheatstone bridge. Bonding pads are applied, and wire is bonded to the circuit to provide a power egress, then the whole thing is coated with an encap-sulation layer to protect the thin lm.According to Richards, the lack of adhesive promotes more intimate contact and long-term stability and better repeatability than [is found with] foil gages. When you adhe-sive-bond the foil onto the surface of an object, errors are introduced. Te more materials you have between the thing that is actually doing the sensing and the thing that is doing the moving, the more error you have.Te thin-lm strain gage has proven itself in applications where small size is required. Te smallest such gage Strain Measurement oers is 6.35mm, according to Richards. One application is in the medical eld. Delivery of uids to the body via pumps or irrigation systems in implantable medical devices can be interrupted by a pinched tube or pump failure. Engineers often use tube sensors to monitor pressure in the pump system by measuring the force exerted onto a sensor pressed against the expanding walls of tubing. Or they place the sensor behind the pump to record pressures as the pump backs up against the sensor during operation.Semiconductor strain gages, used mainly for manufac-turing transducers, operate the same way as metal-foil and thin-lm gages, but they are not produced the same way. Tey are made with single-crystal silicon instead of metal foil.We dont have to etch gridlines in the silicon; it is all one piece, said Rick Lester, semiconductor lab manager at Micron Instruments, a Simi Valley, Calif., manufacturer of semiconductor gages. Te silicon itself is the resist. Ours are mounted right to the unit, and then they are encapsulated with a protective coating. We can put them on a carrier, but when people want something really small they use the indi-vidual strain gages.Tese types of gages are well-suited for measuring small amounts of strain because of their high sensitivity. Te semiconductor gage has a lot more electrical output than a metal-foil gage, Lester said. Foil gages have extremely low output. With semiconductor gages, you can get a much stronger signal. You have better resolution, so you can check very minute movement.Because semiconductor gages have higher resistance than metal-foil gages, less material is required, which means they can be smaller. Our smallest is 0.0018" (0.025mm) long, said Lester. An interesting application involves placing the gage in a capsule that enters a patients heart to monitor it.Disadvantages of semiconductor gages are that they are more sensitive to temperature variations and are more expensive than metal-foil gages. Also, handling is more di -cult because they are brittle.About the author: Susan Woods is a contributing editor to MICROmanufacturing. E-mail: susanw@jwr.com.By Susan Woods, Contributing EditorTo satisfy the requirements for micro-machining applications, spindle manufacturers continue to develop products that are faster and more compact, accurate, powerful and thermally stable.One area of special interest for spindle manufacturers is Swiss-style machines. For example, NSK America Corp. last year intro-duced the iSpeed3 spindle series for live tooling on Swiss-style automatic lathes. Te spindles have an integral electric DC brush-less motor and an accuracy of less than 1m TIR, according to the company. Te iSpeed3, which has a maximum length of 103mm, is intended as a replacement for a machines standard spindle, noted Dick Garski, senior sales manager for the spindle manufacturers U.S. sales o ce in Schaumburg, Ill. Te series includes 19.05mm- and 20mm-OD spindles with a variable speed from 1,000 to 80,000 rpm and 22mm- and 25mm-OD spindles with a variable speed from 1,000 to 60,000 rpm. Tese spindles are designed to increase the speed of the machine, Garski said. Te standard rpm on most of those Swiss-type machines is 8,000 rpm for live tooling.Micropart manufacturers desire high spindle speeds not only to achieve an adequate chip load but also to boost produc-tivity when running microscale cutting tools. Its going to take forever to machine a reasonable-size surface unless youre running at very high speeds, said Chris Gerrard, R&D manager for Westwind Air Bearings. Te Poole, U.K.-based spindle manufac-turer oers units with speeds up to 350,000 rpm for drilling 0.004"-dia. and smaller microholes in printed circuit boards. It also has supplied spindles for micromachining metals, such as brass and aluminum, for the watchmaking industry.Although Westwind produces air-driven, or turbine-driven, spindles with speeds up to 100,000 rpm, Gerrard noted that direct-drive electric motors are the choice when a high-speed micromachining application requires real control. He indicated, however, that turbine spindles are easier to incorporate into a machine, particularly if an end user is doing the upgrade. You dont have to buy a high-speed inverter to get the electric power into the spindle, Gerrard said. You just need an air line and a control valve and away you go. He added that Westwind sells 95 percent of its spindles to machine tool builders.Bill Popoli, president of IBAG North America, North Haven, Conn., agreed that spindles with air-driven motors are typically not powerful enough. IBAG oers its Micro line of spindles with housing diameters as small as 16mm for Swiss-style machines. Te speed range is from 60,000 to 80,000 rpm, and a brushless DC motor delivers the required power and torque, Popoli noted. For a lot of small-part applications, partic-ularly if theyre in medical, youre cutting stainless steel, so theres a need for higher torque, he said.In addition to spindles for Swiss-style Spindle developments for micromachiningMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIICCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRROOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOmachiningIBAG North America IBAGs Micro line for Swiss-style machines includes these 22mm- to 25mm-OD spindles.14|JANUARY/FEBRUARY 2011|MICROmanufacturing micromanufacturing.com|15machines, IBAG is building models for 3- and 5-axis machining centers with automatic toolchangers. Te company has developed a special rotary coupling to put high-speed spindles on lathes with turrets, which require elec-trical or pneumatic connections for the spindles.To illustrate the advantage of an elec-tric spindle compared to a pneumatic one, Garski recalled how a customer near Salt Lake City who was using an NSK air-motor spindle to machine a hexapod drive on a bone screw reduced cycle time from 45 to 15 seconds by switching to an iSpeed3 spindle.Te most critical requirement for virtually all markets, including micromachining, is controlling and minimizing thermal growth of the spindle, according to Bill Howard, product line manager for Makino Inc., Mason, Ohio, a machine tool builder that produces its own spindles. To achieve that, Makino begins by passing temperature-controlled lubricant through the center of the spindle to cool the core. Te technique relies upon long passageways and designed orices to facilitate oil ow, he said, adding that the patented process attacks heat gener-ation at its sourcethe spindle core.Eectively lubricating spindle bear-ings also keeps thermal growth in check, but as spindle bearings spin faster and faster, centrifugal force prevents lubricant from reaching the inner bearing race, where it is needed, Howard explained. Terefore, Makino provides under-race lubrication to ensure lubrication and temperature control. Were lubricating the bearings from the inner race out, he said.Makino reports that a third method to control thermal growth is to add a cooling jacket that encloses the inte-gral spindle, which means the armature, windings and motor are part of the spindle. Te jacket connects to an Oilmatic, or chiller, unit that tightly controls spindle lubrication tempera-ture, relative to the machines bed. Tis ensures that the spindle and bed main-tain a constant, controlled relationship, providing a temperature-controlled manufacturing platform, Howard noted. Even microns of thermal growth in the spindle are going to cause issues in micromachining, he said.About the author: Alan Richter is senior editor of MICROmanufacturing. Telephone: (847) 714-0175. E-mail: alanr@jwr.com.By Alan Richter, Senior EditorEndMi l l Sol ut i onswww.advancedtool.com sales@advancedtool.comTel: 800.343.0210 - Fax: 313.768.4807 Marcy, New YorkHigh Production MillingWe design for youfrom Aluminum to Titanium & everything in between!Specialty Micro End Mills from .010 to .125NSK AmericaThe iSpeed3 series electric-powered spindles from NSK America provide speeds up to 80,000 rpm and are for live tooling on Swiss-style automatic lathes.Westwind Air BearingsA 1mm, single-crystal-diamond tool on a Westwind 160,000-rpm spindle machines brass samples at Cranfield University.16|JANUARY/FEBRUARY 2011|MICROmanufacturingLLLLLLLLLLLLLLLLLLLLLLLLLLAAAAAAAAAAAAAAAAAAAAAAAAAASSSSSSSSSSSSSSSSSSSSSSSSSSEEEEEEEEEEEEEEEEEEEEEEEEEERRRRRRRRRRRRRRRRRRRRRRRRRRpointsGas gives big assist to many lasing jobsMany of todays laser processes are performed with an assist gas, which is a pressurized stream of gas directed either coaxially with or lateral to the laser beam. In cases where an assist gas isnt required, its often applied to reduce processing time and enhance workpiece quality.Assist gases are used in laser oper-ations like cutting, drilling, welding, deposition and surface alteration. A common application is the production of stents: coronary, urinary, urethral/prostatic, colonic, duodenal, vascular and peripheral vascular. Te stents are made from biocompatible metals that are laser-cut in ways that give them the exibility to be snaked through the body and su cient rigidity to hold open the orice into which they are being inserted. Kerf widths of tens to hundreds of microns are typical, and outstanding surface nish is a mustespecially for drug-eluting stents. A typical vascular stent has a wall thickness of about 0.003" and strut-size tolerances around 0.0003". Te required surface nish is about 0.00015" (mirror nish), or 5 percent of wall thickness. Such requirements couldnt be met without an assist gas.Among the reasons to apply assist gases are:To remove molten debris from the workpiece surface. E cient removal of slag minimizes post-process cleaning and helps protect the lasers lens. Cool the workpiece.Inhibit oxidation. Frequently, a cover gas is applied that blankets the processing area with an inert gas. Doing this prevents oxidation at the high temperatures associated with laser welding and laser cutting of metal. (Note: Te process some-times is performed in an enclosed environment, like a laser glovebox.) Enhance oxidation, which speeds the burn process. Tis is often done when cutting stainless steel.Assist gases are teamed with infrared lasers more often than ultraviolet lasers. One reason is that, generally, IR lasers are used to welda common applica-tionand UV lasers are not. Te short wavelength and associated short pulse length of the UV laser do not lend themselves to joining applications. gradientlens.com 800.536.0790High Quality, Simple, AffordableVIDEO MICROSCOPEQ f/4.5 Zoom LensQDigital Video Image CaptureQOptional Borescope AttachmentQMade in the USAQDocumentation andMeasurement Software +/- .001QComfortable Viewingvs. Stereo MicroscopesQ15x - 200x MagnicationLuxxorVideo Microscopes Computer and monitor not included.Starting at $4,995!From the makers of:Visit us at: Booth 954 Aneheim, CAFebruary 8-10, 2011Pressure GageAssist Gas InletLaser BeamLensWorkpieceGas Jet and Focused BeamWhen an assist gas is delivered coaxial with the laser beam, beam centering is critical. micromanufacturing.com|17Another reason is that UV spot sizes are generally much smaller than IR spot sizes, meaning there is less molten material for an assist gas to remove during a UV-laser operation. Finally, with the exception of excimer lasers, UV lasers are generally delivered through galvanometer beam-delivery systems. Tese do not lend themselves to coaxial gas processing.Two UV applications where assist gas is used are pulsed-laser deposi-tion and laser cleaning. Tin lms of HtSs (high-temperature superconduc-tors) can be deposited uniformly and rapidly with UV lasers and the appro-priate gas environment. Other coatings can be applied by this method as well, including thin lms of crystalline and amorphous silicon. Laser cleaning systems for the semi-conductor market remove organics from wafers. One of them, a patented cleaning technology from UV Tech System, Sudbury, Mass., utilizes green gases coupled with laser light to remove organic materials from the surface of silicon wafers and other substrates. Te light and gas reaction creates a gas reaction zone that photochemi-cally and/or photo-ablatively removes selected material from the surface. No solvents or chemicals are requiredonly an inert gas like oxygen or nitrogen.Te most common assist gas applied in traditional laser processing is CDA (clean, dry air). Because the slightest presence of water will kill many processes, the air needs to be extremely clean, dry and pure. Other gases usually have some purity specication.An obvious choice to enhance oxida-tion is pure oxygen. Used for cutting and drilling certain metals, it generally is placed in the reactive-gas category.In order to limit oxidation, such as when welding metals, an inert cover gas is used. Tese gases include nitrogen, helium, neon and argon. A light gas like He moves quickly and can easily enter very small spaces. Larger gas molecules, like Ne and Ar, are heavy and tend to make better cover gases. Tey have enough massand therefore momentumto deect ejected material from the processing area. Even H2 and CO2 are used on occasion. It has been shown that gas mixtures sometimes perform better than pure gases. Laser cutting and drilling metals usually create a HAZ (heat-aected zone) that sometimes must be removed with a secondary process. Tis is undesirable and can be minimized or eliminated by applying the right gas mixture. Steel, for instance, responds well to a mixture of O2 and N2. Stain-less steel and aluminum respond well to a mixture of N2 and CDA, while tita-nium and nickel alloys respond well to Ar and He.Welding requires an assist gas to perform three main functions: protect the HAZ from oxidation, minimize plasma eects in the weld area and expel plasma from the weld joint. Helium is the gas of choice because of its high ionizing potential and minimal metallurgical concerns, but it is expen-sive. Argon is less expensive, but it has a lower ionizing potential and the perfor-mance is not as good as with He. Here again, a gas blend may be preferable.By Ronald D. Schaeffer,PhotoMachining Inc.gradientlens.com 800.536.0790Visit us at: Booth 954 Aneheim, CAFebruary 8-10, 2011Hawkeye Pro MicroFlex BorescopesDiameters as small as 0.5 mm! Hawkeye MicroFlex Semi-Rigid and Flexible borescopes have a 10,000 ber bundle delivering very good image quality in sucha small diameter package.Made in the USA.MicroFlex Semi-RigidAt only 0.9 mm (.035) indiameter, the very exibleNitinol sheathed MicroFlex Semi-Rigid models are six-inches long, and available in both 0 and 90 DOVs. MicroFlex FlexibleThe polyimide sheathed MicroFlex Flexible is now availble in diam-eters of 0.5 mm (.020), 0.9 mm (.035), and 1.5 mm (.059), and lengths up to one-meter (39.4). Gas pressure is vital and can vary greatly. For micromachining purposes, 80 psi probably is suffcient.18|JANUARY/FEBRUARY 2011|MICROmanufacturingLLLLLLLLLLLLLLLLLLLLLLLLLLLAAAAAAAAAAAAAAAAAAAAAAAAAAASSSSSSSSSSSSSSSSSSSSSSSSSSSEEEEEEEEEEEEEEEEEEEEEEEEEEERRRRRRRRRRRRRRRRRRRRRRRRRRRpointsGas pressure is vital and can vary greatly. For microma-chining purposes, 80 psi probably is su cient. Applications involving larger lasers, though, call for pressures up to 300 psi and ow rates up to 1,000 standard cu. ft./hr. Beam centering with a coaxial delivery system is extremely important, especially when trying to achieve consistent results in multidirectional cutting. For the oxygen-assisted cutting of steel, for example, concentricity should be within 50m. Centering of the gas nozzle is done after focusing. When coaxial gas-assist delivery is not possible, external nozzles can be used to direct the gas at the target area obliquely. Te direction of the gasi.e., toward, away from or perpendicular to the direction of travelcan make a big dierence in on-target quality.Finally, a key to maintaining excellence in processing over an extended time period is to consistently apply high-quality gases. Tis is achieved by partnering with a supplier known for providing a pure product. About the author: Ronald D. Schaeffer, Ph.D., is CEO of PhotoMachining Inc., a high-precision laser job shop and systems integrator in Pelham, N.H. E-mail: rschaeffer@photomachining.com.The worlds most compact and powerful high speed spindles for Swiss machining Eliminate secondary operations for Swiss Type lathes Built for fine drilling, milling, engraving in micro machining, and medical applications 60,000 to 100,000 rpm 20, 22 & 25 mm diameter spindles-right angle spindles also available Reduce machining time, improve productivity and increase profitswww.ibagnorthamerica.comIBAG North AmericaTel. 203-407-0397 Fax 203-407-0516e-mail: sales@ibagna.comThe NEW I BAG MICRO LINEThe NEW I BAG MICRO LINEFREE WEBINARM 1Micro Milling C8 www.cimatrontech.com1 l M Lu1 micromanufacturing.com|19DDDDDDDDDDDDDDDDDDDDDDDDDOOOOOOOOOOOOOOOOOOOOOOOOOWWWWWWWWWWWWWWWWWWWWWWWWWNNNNNNNNNNNNNNNNNNNNNNNNNsizingBy Dennis Spaeth, Electronic Media EditorWhen Alexander Graham Bell called Mr. Watson one Friday back in March 1876, he probably wanted to cele-brate the invention of the telephone. But Bells rst phone call should have been to his team of patent attorneys so they could begin preparing for the decades-long legal battles that followed.Tough this digression into telephone history may seem o topic, hold the phone. You see, Bells breakthrough led another American inventor, Emile Berliner, to come up with a better telephone transmitteror, as history would have it, the rst microphone. Te American Bell Telephone Co. was paying attention and quickly purchased the rights to Berliners patent.Shortly thereafter, Tomas Edison invented the carbon microphone, which Bell Telephone would eventually own as well. Of course, carbon microphone technology, which was used in phones for the next 100 years or so, didnt escape a patent battle of its own. Unlike the telephone patent chal-lenges that continued in one form or another until 1897, the microphone battle pitting Bell and Berliner against Edison was resolved in Edisons favor by 1892.So much for my childhood memories of who invented what. Yet if this not-so-nostalgic trip into microphone history teaches us anything, it is that many people contribute to such inventions, and that tech-nology progresses despite whatever legal battles may ensue. Indeed, microphone patent disputes have managed to span more than a century of technological advancesfrom the condenser microphone in 1916 to the electret condenser microphone (ECM) in 1962 to the MEMS-based microphones that have evolved over the past two decades. Today, though, patent lawsuits surround the microelectromechan-ical processes involved in producing the millions of tiny MEMS-based microphones used in cell phones, smart phones, personal computers and laptops.Te legal turf battles are understandable, given that the market for MEMS microphones is forecast to grow from just under 700 million Speaking of smallWhile microphones still come in all shapes and sizes for a wide variety of applications and needs, they too have done well in the march toward miniaturization. The Akustica Inc. MEMS microphone shown is 1mm x 1mm x 0.4mm. Silicon die image courtesy Akustica Inc.DDDDDDDDDDDDDDDDDDDDDDDDDDOOOOOOOOOOOOOOOOOOOOOOOOOOWWWWWWWWWWWWWWWWWWWWWWWWWWNNNNNNNNNNNNNNNNNNNNNNNNNNsizing20|JANUARY/FEBRUARY 2011|MICROmanufacturingunits shipped in 2010 to more than 1.7 billion units in 2014, according to iSuppli Corp., a market research rm based in El Segundo, Calif. Tats not a particu-larly surprising forecast considering smart phones began incorporating two MEMS microphones in 2010, in a move to suppress background noise, and are expected to incorporate even more such microphones by 2014.Although noise suppression has been available since 2006, the arrival of Motorola Inc.s Droid as well as the iPhone 4 (from Apple) has caused the popularity of the technologyand of MEMS microphonesto soar, iSuppli observed in a report accompanying its latest forecast. Whats more, iSuppli noted that MEMS microphone makers should nd it easier to compete with Knowles Electronics LLC, Itasca, Ill., thanks to a Nov. 22, 2010, U.S. International Trade Commission ruling that the companys silicon microphone patents were invalid. Knowles, which is cred-ited with successfully commercializing MEMS microphones in 2003, remains the category leader, and accounted for more than 80 percent of the devices shipped worldwide in 2010, according to iSuppli.While the ITC ruling is sure to be welcome news for MEMS microphone competitors such as Analog Devices Inc., Norwood, Mass., this and similar legal challenges have done little to impede the technological progress of the MEMS microphoneparticularly where size is concerned.In fact, from 2003 to 2008 MEMS-based analog microphones dropped in size from 4mm 6mm to about 4mm 4mm. Ten in 2008, Akustica Inc., a MEMS microphone maker based in Pittsburgh, rolled out the worlds smallest MEMS microphone at 2mm 2mm.Tese dimensions, however, refer to the overall MEMS microphone package that must adhere to standard micro-phone footprints, which shrink more slowly than the die inside, observed Dr. Marcie G. Weinstein, marketing strate-gist at Akustica.Te size of Akusticas analog micro-phone die measures just 1mm 1mm and about 0.4mm thicka feat owing directly to an acoustic MEMS tech-nology for which Akustica holds the exclusive patent rights. Te technology allows Akustica to fabricate both the 715.247.3500inquiry@smcltd.comAt SMC Ltd., we understand that precision matters at every size. Through our proprietary micro molding process and in-house tooling capabilities, we offer complex part geometries with fast lead times and high repeatability on even the smallest components. When details are critical, choosing a supplier that understands precision can make the difference. To see how we can partner with you on your next medical device or to sign-up to receive our case studies visit: www.smcltd.comPrecision at every sizeMicro Molding:Legal challenges have done little to impede the technological progress of the MEMs microphoneparticularly where size is concerned.continued on page 45 The 6th International Conference on MicroManufacturing ICOMMJ2011 March 7 - 10, 2011 Tokyo, Japan Held on the campus of Tokyo Denki University in the Kanda district of Tokyo 70 to 80 papers will be presented in technical sessions and published in the conference proceedings (bound volume & CD). Theoretical and applied research related to manufacture, assembly and metrology for components and systems with micro/meso-scale features will be presented. Topics

A broad range of processes:machining formingEDM and ECMLaser-based processes casting and molding others; Applications of current and emerging micromanufacturing methods; The microfactory paradigm;Micro-scale metrology;Materials handling and joining; Micro-assembly;Multi-scale modeling and simulation;Design for micro manufacturing; Materials-related issues at the Mechanics and dynamics of process behavior at the microscale;Miniaturization of machines and equipment:toolingfixturingpositioningmotion generationsensor systemscontrol;Contact Takashi Matsumura, Professor Tokyo Denki UniversitySecretary, ICOMM 2011 Phone: +81-3-5280-3391Fax: +81-3-5280-3568 E-mail: tmatsumu@cck.dendai.ac.jp Industry Tour A post-conference tour will be organized to RIKEN - The Institute of Physical and Chemical Research.RIKEN is Japans flagship research institution devoted to basic and applied research. The tour will visit the Ohmori Materials Fabrication LaboratoryExhibition A micromanufacturing technology exhibition will be held during the conference. Manufacturers of micromanufacturing equipment, micro-tooling, metrology and precision devices will be available to demonstrate and discuss their products.Exhibition space is still available.>22|JANUARY/FEBRUARY 2011|MICROmanufacturingContinuedgrowthintheU.S.market forimplantablemedicaldevicesshould translate into both growing opportunities and challenges for companies that mold and machine tiny implant parts.In the U.S., demand for implantable medical devices is projected to increase by more than 8 percent a yearto almost $50 billion in 2014, accordingtoTeFreedoniaGroup,aCleve-land-basedmarketresearchrm.Inareport entitled Implantable Medical Devices to 2014, Freedonianotesthatgrowthintheimplant market will be spurred by the development of newdevicesfeaturingnoveltechnologiesand bettermaterials.And,ineectivedrugtreat-mentmethodsareexpectedtoincreasethe useofimplantabledevicesforcardiovascular, neurological, orthopedic and other conditions, reports Freedonia. Intheareaofso-calledactive-implantable medical devices (AIMDs), which are activated byelectricityorsomeothertypeofenergy, Freedonia forecasts demand for cardiac implants to rise more than 7 percent annually, to about $17 billion in 2014. Key segments of this market includecardiacresynchronizationtherapy devicesthecategoryexpectedtoexperience the strongest growth among pacing devicesas well as implantable cardioverter debrillators and cardiac pacemakers.Among other AIMDs, Freedonia is bullish on the prospects for implantable stimulators used to treat neurological conditions. New stimula-tiondevicesandapplicationsareexpectedto boost demand by nearly 8 percent annually, to $1.3 billion in 2014.Asfororthopedicimplants,Freedoniasees U.S. demand increasing almost 9 percent annu-ally, reaching nearly $26 billion in 2014. Among themarketstoexperiencethehighestgrowth ratesisthatforreconstructivejointreplace-ments.Spurringthegrowthareimproved productsandtheactivelifestylesofanaging population.Freedoniaalsoexpectsstrong growthforspinalimplants,dueinparttothe increase of people with chronic back problems, andtraumaxationimplants,suchasplating systems for fractures near joints.MTD Micro MoldingEDMing a micromold for implant parts.Implant Nation Smaller parts, larger marketsCover StoryBy Bill Leventon, Contributing Editor micromanufacturing.com|23Freedoniapredictsthemarketfor cardiac stents and stent-related implants will grow more than 9 percent per year, to over $7 billion in 2014, due in part to the introductionofimproveddrug-eluting stents, as well as strong demand for prod-ucts such as endovascular stent-grafts and stents for treating carotid artery disease.Tecarotidstentmarketalsolooks promisingtoVenkatRajanofFrost& Sullivan,SanAntonio,Texas.Overall, Rajan,whotracksmedicaldevicesales forthemarketresearchrm,predicted onlymodestgrowthforU.S.implant markets,whosecombinedannualsales heputataround$31billion.Forthe most part, Id say that the implant markets intheU.S.arefairlysaturated,hesaid. Therearesomesegmentsthathave moreopportunityaheadofthemthan others,buttherearenttoomanythat have double-digit growth rates.Like Freedonia, Rajan also sees strong growthpotentialforneurostimulation devicesimplantedinpatientswhoare unresponsive to rehabilitation and phar-maceutical treatments. On the downside, he believes this market is limited by the fact that the products, though capable of enhancingthequalityoflife,arentlife-saving in nature.Rajanisalsooptimisticabouttrans-catheter valve technology, which he views as a signicant new development in the implantmarket.Tetechnology,which allowsreplacementofheartvalvesina minimallyinvasiveprocess,opensup anat-riskpatientpopulationthatyou potentially werent able to address before because you dont have to crack open the chest, he noted.Shrinking parts, new materialsDuetodemandforever-less-inva-sive medical devices, the size of implant partsgrowseversmaller.Ifwemade something [at a certain size] 3 years ago, today were probably making it half that size, said Brian Hrouda, director of sales andmarketingforNormanNobleInc., acontractmachiningrminHighland Heights, Ohio. And we continue to see that trend moving forward.Tomeetthepart-sizerequirements of medical OEMs, Norman Noble plans ahead. If a customer tells us, Down the road, we want this part to be half the size it is now, well start developing a process to do that, Hrouda said. And well design manufacturing machines or equipment to make what they want.Other implant trends involve the use ofmaterials.Atpresent,forexample, Norman Noble is experiencing increased demandforimplantpartsmadeof Micro PrecisionMolding Machines VerticalAdd On Injection UnitTel:909.941.0600 U800.432.6653 UFax:909.941.0190 Email:albaplas@albaent.com Uwww.albaent.comJohnson Matthey Medical microparts machined by Johnson Matthey from platimum/iridium alloys, 316 stainless, Nitinol and titanium.24|JANUARY/FEBRUARY 2011|MICROmanufacturingNitinol,ashape-memoryalloy.Hrouda attributed this to medical OEMs success with Nitinol implant components, as well as a better understanding of the material among product designers and regulators.Foryears,NormanNoblehasbeen lasermachiningNitinoltubestocreate stents.Now,however,thecompany also can machine Nitinol bar stock with Swiss-stylemachines.Withitsunique characteristics, Nitinol allows engineers todesignproductsthatcantbemade withstandardmaterials,Hroudasaid. But the problem has always been that if you couldnt laser-machine the product becauseofgeometryrestrictions,you couldnt make the product out of Nitinol. Now, our Swiss capability is opening the door to things like Nitinol bone screws and other exciting new products.Demand is also increasing for implant partsmadeofplatinum.Accordingto Hrouda,manufacturingmethodsare now available that allow machining plat-inum parts with dimensions that werent possible in the past. For example, his company developed aprocesscalledNobleUltralight,an athermallasermachiningtechnique developedtocutprecisefeaturesin bothmetalsandpolymers.Sinceit doesnt produce a heat-aected zone, the processcanmachinesmallerholesand other features in platinum parts than are possible with heat-generating techniques. In addition, Hrouda pointed out that theathermalprocesseliminatesthe needforpost-processingsteps,suchas cleaning and electropolishing, which can adversely aect features with microscale dimensions.In some cases, platinum is combined with another material that adds strength or other properties. For example, a plat-inumalloythatincludes10percent iridium is commonly used to make long-termimplantablepartsthroughwhich electrical signals pass, said John Morley, medicalproductmanagerforJohnson Matthey,aU.K.-basedglobalmaterials supplierthatalsomicromachinesparts made of platinum and other metals. Te partsincludeactivexationleadsthat attach pacemakers to the heart. Te leads, madefromaplatinum-iridiumalloy, oer both biocompatibility and electrical conductivity, according to Morley. MuchofJohnsonMattheysmedical business involves platinum-based prod-ucts.Butwiththepriceofplatinum soaringalongwiththepricesofother commoditiesmanufacturers are looking for less-expensive alternatives. Terefore, JohnsonMattheyoerscustomersthe optionofswitchingfromplatinumto alloysbasedonpalladium,whichcan oerpart-to-part material cost savings of about 75 percent compared to platinum, accordingtoMorley.Asformechan-ical properties, Morley maintained that thetwomaterialsareinterchangeable, though he added that there may be subtle dierencesbetweenthetwomaterials when used in implants.Withcomparablepropertiesanda much lower price, palladium would seem to be a good deal for implant manufac-turers.Onedrawback,however,isthe fact that palladium is new in the medical device industry. When you adopt a new technology in this industry, you have to answer a lot of questions from the FDA, Morleysaid.Allthesequestionshave beenansweredforplatinum,butthey have yet to be answered for palladium.In addition to using readily available materials, Hrouda reported that implant OEMS are working closely with material suppliers to develop proprietary custom alloysandpolymerformulationsthat willallowtheOEMStoachievetheir product-design goals. In some cases, he added, the material is a bigger concern to the OEM than the part design because ofitsimpactonpartperformance. Processingexoticnewimplantmate-rialscomplicatesmattersforrmslike Norman Noble, because it has to learn how to machine them.Implant Nation continuedImplantable medical device demand ($ millions)% Annual growthItem 2004 2009 2014 2019 2004-2009 2009-2014Implantable medical device demand 19,870 32,860 49,050 70,900 10.6 8.3Orthopedic implants (total):10,290 16,900 25,800 38,400 10.4 8.8Reconstructive joint replacements 4,860 7,160 10,490 15,350 8.1 7.9Spinal implants 2,270 4,4607,500 11,800 14.5 11.0Orthobiologics 1,4102,7404,1706,100 14.2 8.8Trauma xation implants1,7502,5403,640 5,1507.77.5Cardiac implants (total):7,460 12,280 17,600 23,700 10.57.5Pacing devices 4,460 6,7309,000 11,900 8.66.0Cardiac stents 2,300 4,540 7,1009,540 14.69.4Structural cardiac implants700 1,010 1,500 2,260 7.6 8.2Other implantable medical devices2,1203,6805,650 8,80011.7 9.0The Freedonia Group Inc.RapidwerksPolymer bone screws molded by Rapidwerks. micromanufacturing.com|25Materials arent the only complicating factor when it comes to making implant-ablemicroparts.Forexample,Hrouda notedthatsomeofthesepartsareso small that they cant be moved individu-ally with ngers or tools. Instead, batches oftinypartsaremovedtogetherinan automated process. Norman Noble can attach roughly 1,000 parts to xtures the sizeofapenny,whicharethenmoved using proprietary automation technology. Complicationscanariseduring machining as well. Johnson Matthey, for instance, has found that a single machine oftencantdoeverythingrequiredto make very complex and/or high-quality micropartsforimplants,according toMorley.Terefore,thecompanyis performingmoresecondaryoperations onceaninitialmachiningprocessis completed. Tomakepartsforthevasculature system, for example, the rm starts with Swiss-style machining and then turns to EDMingtocreateverysmall,burr-free holes in the parts that allow the passage of uid inside the body.Anothertwo-machineprocessis usedtomaketinyelectrodesforthe neurostimulationdevicesthatattachto thespinalcord.First,JohnsonMatthey usesproprietarytechnologytocut match-head-sizeelectrodebodiesfrom tubesmadeofelectricallyconductive precious metals. Ten, the rm switches to EDMing to cut lengthwise slits in the tubes. An EDM puts essentially no force ontheseveryneparts,soyourenot deforming them when youre cutting the slits, Morley explained.Machined to molded partsDespitesucheffortstosatisf y customers,machiningmaybefalling outoffavorwithsomeimplantmanu-facturers. For a number of implant types, therehasbeenafairlylargetransi-tionfrommachinedtomoldedparts, accordingtoScottHerbert,president of Rapidwerks Inc., a Pleasanton, Calif., molder of microparts.Itwasoncethoughttobeimpos-sible to mold the tiny features on some Screw machines for making microparts at a Johnson Matthey manufacturing plant in San Diego. The plant also uses wire and sinker EDMs, and lasers for cutting and welding.Johnson Matthey 26|JANUARY/FEBRUARY 2011|MICROmanufacturingoftheseparts,Herbertsaid.Butnow thatwehavetheabilitytomoldthem, companies that typically machined both metalsandplasticsareleaningtoward molding the same materials. In the case ofspinecages,machiningcostsmight be $170 versus less than $10 to mold the same part, with no secondary machining, deburring or cleaning required after the molding process, he noted.Herbert also maintained that molding can give implant part designers more ex-ibility than machining, allowing designs withcomplexgeometriestobemanu-factured.Insomecases,youmaynot be able to machine a specic geometry, but you may be able to mold it and create somethingthatsmorebenecialtothe application, he said.As for materials, Herbert sees another transition, this one from metals to plas-tics.Forexample,hesaidthatimplant manufacturers are looking to replace tita-nium with polymer materials that are less expensive but oer similar performance properties.One such material is PEEK (polyether ether ketone), which oers high structural strength. PEEK isnt an exact match for titanium in terms of structural strength, Herbert noted, but for a polymer-based material, its pretty darn good.MTDMicroMoldingofCharlton, Mass.,whichspecializesinmolding microparts, is working with an implantable PEEK grade thats carbon-ber-reinforced for higher strength. Tis material is suit-able for applications such as bone anchors thataresubjectedtohighloads,said Dennis Tully, president of MTD.Onthedownside,suchhighlyengi-neeredmaterialscanbedifficultto process.Forexample,Herbertnoted thatmoldingthematerialscanrequire temperaturesinexcessof750F,higher thanthosecommonlyencounteredby most injection molders.PEEKisalsoacostlymaterial,so molders must keep their runner-to-part weightratiosmuchlowerthanthose usedincommonmoldingoperations. Herbertsaidanappropriateratiofor molding PEEK might be 6:1, as opposed tothe60:1ratiothatmightbeusedin ordinarymoldingjobs.Whenyoure molding materials that cost a few thou-sand dollars a kilogram, molding a runner [that outweighs the part by] 60:1 is a very expensive proposition, he added.Despiteitshighcost,PEEKmaybe specied for implants because its already well-documentedformedicalapplica-tions,savingusersalotoftroublein qualifyingtheirmaterials.Tus,they haventarrivedatthatmaterialfroma properties standpoint; theyve arrived at itfromaconveniencestandpoint,said Tully, adding that specifying PEEK when aless-expensivemateriallikepolypro-pylene would do the job is not necessarily a great approach in the long term.Asforothermaterialtrends,Tully reportedthatMTDcustomershave recentlybecomeinterestedinTPE (thermoplasticelastomer)andTPU (thermoplastic polyurethane) for neuro-stimulation devices. Te impulse-carrying parts involved must be exible enough to allowtheirpassagethroughthebody, which Tully believes is the reason for the Implant Nation continuedMOLDED PARTS USED IN IMPLANTABLE medical devices that come into contact with human tissue must meet stringent quality standards. Meeting those standards starts in the design process and continues through manufacturing and packaging. One key design consideration is minimizing parting-line height, according to Brent Hahn, senior sales engineer for Ankeny, Iowa-based Accumold, which specializes in molding parts down to the size of a grain of sand.The alignment of parting lines must be extremely precise, because if they are not you can create ash, he said. The larger the gap between the mold halves, the greater the chance of creating a sharp edge that can break off when the part is used. And even if doesnt, that sharp edge might damage human tissue.While parting lines will always remain on a part, where those lines are placed is critical. There will always be a least two halves creating a 360 parting line, and if you add slides, inserts or other features, there will be more, he said.There may be grooves or other features in the part that must not have parting lines, but the molding process may also dictate the location of parting lines, so an ongoing dialog between the molder and the medical OEM during design is crucial.During the molding process itself, a cleanroom is required that meets at least Class 100,000 standards. A greaseless mold is also preferred to eliminate possible contamination from oil, grease and mold-release agents. Also, resins used for medical parts must be protected from degradation during processing. Medical OEMs choose resins with specic properties, but those properties can be degraded when using equipment with excessive residence times, said Hahn. This has long been a challenge for Considerations when designing and molding medical partsAccumold(515) 964-5741www.accu-mold.comThe Freedonia Group(440) 684-9600www.freedoniagroup.comFrost & Sullivan(877) 463-7678www.frost.comJohnson Matthey Inc.(800) 442-1405www.mathey.comMakuta Technics Inc.(317) 642-0001www.makuta.comMTD Micro Molding(508) 248-0111 www.mtdmicromolding.comNorman Noble Inc.(800) 474-4322www.normannoble.comRapidwerks Inc.(925) 417-0124www.micromolding.comContributors micromanufacturing.com|27material choice.Polymers are also being developed that will allow devices to safely reside in the body for long periods of time, according toStuKaplan,presidentofMakuta TechnicsInc.,amicromoldingrmin Shelbyville, Ind. Were learning so much more about these kinds of materials than weknewafewyearsago,saidKaplan, whosecompanyiscurrentlyworking withthematerialsonanexperimental basis.Manyofthedevelopmentsare condential,headded,butnotonlyis it happening, its being commercialized.Still,manymedicalOEMsremain unaware of what can be done by leading micromolders, suggested MTDs Tully. Wehavealotofconversationsthat startwithsomeonesayingsomething like,Iknowthisdesignisntgoingto bepossible,butwehadtostartsome-whereandIwantedyoutolookatit, Tullysaid.Butmanytimeswelookat it and say, Tis is nowhere near impos-sible. In fact, its not all that di cult by todays standards. About the author: Bill Leventon is a New Jersey-based freelance writer. He has a M.S. in Engineering from the University of Pennsylvania and a B.S in Engineering from Temple University. Telephone: (609) 926-6447. E-mail: wleventon@verizon.net.Editors Note: Copies of the report Implantable Medical Devices to 2014 can be purchased at The Freedonia Group Web site: www.freedoniagroup.com. For more information, go to the Medical and Pharmaceutical Products page.Dedicated to the Science ofMotionAerotech, Inc., 101 Zeta Drive, Pittsburgh, PA 15238Ph: 412-963-7470 Fax: 412-963-7459 Email: sales@aerotech.comwww. aerot ech. comAH0510F_PPSA e r o t e c h Wo r l d w i d eUni t edSt at esGermanyUni t edKi ngdomJapanChi naIntegral cable management formulti-axis systemsAdd an Aerotech award-winning single- or multi-axiscontrol system for a completemotion solution.The ANT180-L offers nanometer resolution,superior bi-directional repeatability, andoutstanding in-position stability for high-accuracy alignment, measurement,scanning, and other demandingapplications. The direct-drive linear motordrives the stage to a peak acceleration of 2 g and maximum velocity of 500 mm/s.The ironless forcer is a cog-free design thatprovides exceptional velocity control. Thedirect-drive linear motor and high-accuracylinear encoder make possible the excellentstep-to-step resolution critical inspectroscopy, optical delay line, and otherprecision applications. Contact an Aerotech Application Engineertoday and see how the ANT180-L canprovide your application with a competitiveadvantage.Anti-creepcrossed-rollerbearings160, 210, 260,and 360 mmtravelsHigh resolution(1 nm),repeatability(100 nm),and accuracy(150 nm)Noncontact,non-cogging,frictionlessdirect-driveInternal cablemanagementSmooth, Precise, Repeatable Excellence in MotionThe Aerotech ANT180-L Series Linear-Motor Positioning StageUltra-stiff two-piece designGet our FREEnano MotionTechnology brochure atwww.aerotech.commolders, he explained. Because of the small shot sizes used when molding these microparts, the heated resin can remain in the machines screw and barrel well beyond recommended residence times. That can break down the chemical structure of the resin; you are literally baking the desired properties out of it, he said. If youre molding a bookmark, it doesnt really matter, but if the part is going into the body, thats a problem.Machinery designed for micromolding can target this problem. For example, Accumold has devised micromolding machines that have much shorter residence times than the industry standard, according to Hahn. After the part is molded, it should be removed from the mold via an end-of-arm robotic tool and be placed in a clean bag or tray. No debris from the gate or contaminants from the mold or press should fall on the parts.While some molded parts are placed in electrostatic-free, high-density polyethylene bags, Hahn recommended standard HDPE bags. Some electrostatic bag makers use soap or corn starch to reduce static, and these additives can contaminate parts [used] for implantable medical devices, he said.Alan Rooks28|JANUARY/FEBRUARY 2011|MICROmanufacturingSomeshopsviewmakingmicropartsona Swiss-style machine as a dark art, but the processisjustadierentstyleofmachining and not something mysterious. Success in this micro realm requires a blend of special tactics, attentiontodetailandtop-qualitytoolsand equipment. Tomachinemicropartsconsistentlyand e ciently,aCNCSwiss-styleautomaticlathe isoftenthebestchoice.Temachinescan routinelyturndiametersdownto0.003"or smaller,machinefeaturesassmallas0.0003" and achieve 0.0002" tolerances. A Swiss-style machine is distinguished from other lathes by a sliding headstock that feeds a rotating workpiece through a guide bushing. Typical bar diameters are from 2mm to 38mm. ASwiss-stylemachineoffersarangeof machiningadvantagesandcapabilities.Static androtatingside-andend-mountedtools cutwithinmillimetersoftheguidebushing, eectively eliminating overhang and part deec-tion.Multipleaxesanddriventoolsenable nonturning operations, such as milling, drilling and deburring. CNC technology permits use of standardtoolgeometriestoproducecomplex and nonround shapes. Twin-spindle congura-tions facilitate nishing of both ends of a part. In sum, the machines can produce small, precise parts complete in one chucking. Segmentation, materialsAmachiningtacticmatchedtoSwiss-stylemachininginvolvessegmentationofthe workpiece.Insegmentation,theworkpieceis machined to completion one section at a time. Te bar is extended a short distance from the guide bushing, turned to size and then subjected tooperationssuchasgroovingorcross-hole drilling.Whentherstsectioniscompleted, anothersegmentofworkpieceisadvanced throughtheguidebushing,turned,machined to create other features and so on. Thesegmentbeingmachinedisclosely supported by the guide bushing, but operations such as peck drilling and single-point threading Swiss-Style SuccessTools, tactics and tips for productive Swiss-style micromachiningBy Glen Crews, Marubeni-Citizen Cincom, and Bill Kennedy, Contributing EditorB. Kennedy micromanufacturing.com|29requirethattheworkbepulledashort distancebackintotheguidebushing (seeillustrationonpage30).Tomain-tain guide bushing support, the pull-back distanceislimitedtothestrokeofthe machine, usually about 58", depending on the conguration of the guide bushing.Te bar or wire workpiece fed through the guide bushing must be large enough indiametersoitdoesntbendortwist duringfeeding,butalsobeascloseas possible to the nished diameter of the parts largest OD. Tesmallestbarmanyshopswork withis 116"indiameter.Mostsmaller-capacitymachines(16mmindiameter and below) handle 116"-dia. material with minimal di culty.Toconsistentlyachievesuchsmall-scaleprecision,itisessentialtohavea workpiecematerialthatismetallurgi-cally and dimensionally consistent. From a metallurgical point of view, some mate-rialsareeasiertomachinethanothers. Forexample,brassandcopperalloys generallymachineeasily.Ontheother hand, stainless steel can be more di cult to machinebut not all grades. Within 300-seriesstainlesssteels,the303alloy isnotaproblemtomachine,whilethe 304 alloy can be very di cult. Bar stock suppliers have developed premium-grade alloystoprovideoptimalmachinability andproducethemundertightmetal-lurgicalspecificationstoensurethat machinabilityremainsconsistentfrom bar to bar. Regardingdimensionalconsistency, barstockformicromachiningina Swiss-stylemachinetypicallyiscenter-less-groundtoadiametrictoleranceof 0.0002". Moreimportantthanabsolutetoler-ances,however,isaconsistentbar Guide bushingSliding headstockSpindle colletWorkpieceSwiss-style machining basicsLive toolEndworking toolTurning toolBar feedB. KennedyIn a Swiss-style lathe, a sliding headstock feeds rotating stock through a guide bushing, eliminating overhang and deflection. 30|JANUARY/FEBRUARY 2011|MICROmanufacturingdiameteralongitsentirelength.Abar may be 0.0005" undersize, but as long as theentirebarisundersizebythesame amount,adjustmentscanbemadeto produce the part dimensions required. In general, a Swiss-style machine can hold 60 percent of bar stock tolerance; that is, if bar stock varies by 0.001", the part can vary by as much as 0.0006". Additionally,barstockshouldbeas straight as possible, exhibiting a bow of less than 0.001" per 12" of length, and be round. If the material is out of round, the machined part will be too. Tathighlightsonedisadvantageof Swiss-stylemachining:anout-of-round barcanbechuckedbetweencentersin aconventionallatheandturnedround, but in a Swiss-style machine, an out-of-round bar will be turning oblong in the guide bushing, and the machined part will be the same shape. Bushing guidanceTheconfiguration,adjustment andqualityoftheguidebushingare majorfactorsinsuccessfulSwiss-style machining.Problemswithdimensional control or tolerances are often the result of an inaccurate or worn guide bushing.Tere are two guide bushing styles. For parts with wider tolerances (greater than 0.0005"),thebushingrotatesinsync with the workpiece material. But tighter tolerances require a xed guide bushing, which remains static while the bar stock spins.Axedguidebushingisadjust-ableandmustbesizedsothatthebar stock is in full contact with the bushing but can still spin freely without seizing. Hand skills and feel for the relationship between the bar and bushing play a role. Formicromachining,high-precision guidebushings,whichcostmorethan standard-qualityones,areneededto maintainmicron-scaletolerances.A goodSwiss-stylemachinewillprovide unvaryingrepeatability,butifthebar stockorworkholdingortoolholding componentsareinconsistent,itdoesnt matter how accurately the machine can repeat. Tooling is one of the most important elements of the micromachining process on Swiss-style lathes. Using tooling engi-neered specically for micromachining is crucial. Until recently, it was di cult to nd insert tools for Swiss-style machines suitableformicromachining.Tetool-noseradiiwerenotsharpenough,and thetoolslackedsufficientclearance anglesbehindthecuttingedge.Fortu-nately,anincreasingnumberofcutting tool manufacturers have realized there is a signicant market for tools engineered for micromachining, and they now oer them. Ingeneral,turningtoolsforSwiss-style machines have sharp edges, 0 nose radii and higher clearance angles behind thecuttingedge.Itshouldberecog-nizedthatthenoseradiusofaSwiss turningtoolisnotlikethatofan80 or55diamond-shapedtool.Toolsfor Swiss-style machines feature a nearly at, 90angle of contact with the workpiece. Te atness of the edge acts like a wiper tool to smooth the work surface. Tetoolsalsohavetobesharp.Te slightly radiused edge of a typical ANSI-standardinsertrequiresmorecutting forceand,therefore,moremachine toolhorsepower.Andconsideringthe extremely light DOC that is characteristic of many Swiss operations, a sharp edge is necessary to ensure the insert actually cutstheworkpiecematerialinsteadof simply pushing it. Swiss-styletoolsoperateinclose proximitytotheworkpiece,andsu -cientclearancebehindthecutting edgepreventsrubbingonthework. Chipbreakersshouldbegroundnot moldedinto the cutting edge to ensure they cut and bend the chip eectively. Finding drillsTe accuracy of Swiss-style machines makeitpossibletodrillholestoa 0.0002"ortightertolerance.Butjust aswithturning,holemakingpresents specic challenges. Tere are a limited number of suppliers that make microdrills. As a result, many shops apply drills meant for other appli-cations,suchasdrillingprintedcircuit boards.A recurring problem with holemaking on this scale is that manufacturing engi-neersoftendesignpartswithhole dimensionsthatdontmatchstandard WHEN MACHINING MICROPARTS ON a Swiss-style machine, programming generally is not as large an issue as tooling. By their nature, microparts do not feature overly complex geometries. There are some truly complicated parts that cant be programmed manually, but there are many others that can be programmed at the machine or ofine. For complex parts, there are Swiss-specic automated CAM systems available, but they can be expensive. A shop should decide whether that level of sophistication is necessary for the parts it makes. If a shop does decide to employ an automated CAM system, it should make sure the programmer learns how to use all its capabilities. The programmer should also know how to program a part manually, so he will be familiar with the codes being generated and have a sense of their appropriateness. A CAM system can generate codes that may not be Swiss-style Success continuedA key Swiss-style machining tactic is segmentation, in which the workpiece is closely supported by the guide bushing and machined to completion one section at a time. Swiss-style programming G. Crews micromanufacturing.com|31letter-andwire-sizedrilldimensions. Somecuttingtoolmanufacturers provide drills down to 0.100mm in diam-eter,in0.010mm-dia.increments,but specialsmaystillbeneededforcertain applications. Regarding special or odd hole sizes, as well as specic part tolerances, it can be benecialforashoptoworkwithpart designers and conrm that the specied hole sizes and tolerances do have func-tionalvalue.Referencedimensionscan replaceunnecessarilytighttolerances thatcanmakeapartacandidatefor failure in inspection, although it is func-tionally perfect. Swiss-style machines are capable of controlling a process beyond what many quality managers or statisti-cians say is possible. Whentightholetolerancesare required,reamerstraditionallyhave been applied to achieve them. Microscale reamers, however, are hard to nd. But evenifappropriatelysizedreamersare available, it can be di cult to determine thereamertolerancethatwillproduce the nal hole size desired. As an example, reamers were unavail-ableforoneholemakingapplication thathada0.0003"tolerance.Tesolu-tionwascustom-made,tight-tolerance drills engineered to achieve the tolerance withoutreaming.Aftertrialanderror determined the exact drill size required, thousandsofpartsweresuccessfully produced. smart grinding smart future info@rollomatic.chwww.rollomaticsa.comWith the Rollomatic GrindSmartSeriesFor the highest quality tool production, the NEW GrindSmart series with the VirtualGrindPro software suite is the right solution for surgical tools, endmills, drills, inserts, thread whirling tools, routers, reamers, taps and more. Rise to the challenges of todays market Visit us at : Rollomatic Booth #3158, MD&M West show in Anaheim CA, from February 8th - 10th 2011suited for what a shop wants to do, but once the codes are produced, a skilled programmer can change them to t a specic application. A shop also needs to adjust recommended cutting parameters found in speed-and-feed charts to t the requirements of a specic job. The recommended parameters are not always achievable because standard machines often cant generate the high surface speeds required for very small parts and tools. In turning, for example, reaching the recommended surface speed for a very small part may require a spindle speed of 25,000 to 30,000 rpm, a speed generally not available on standard machines. In some cases, however, a machine can be upgraded. A machine builder can provide certain modications that boost effective machining speeds, including spindle liners and reduction sleeves for the pickoff spindle. Compromises often are necessary and, in many cases, are quite effective. Tool geometries play an important role in nessing machining parameters. For example, sharper geometries work better at slower surface speeds. It will come down to testing and experience; when a part is machined, the results can be documented and a cause analysis performed to nd what is causing the result. G. Crews, B. Kennedy32|JANUARY/FEBRUARY 2011|MICROmanufacturingAnotherissueispartnishing.For example, burrs that are insignicant on large parts can cause major problems on microparts.Inmanycases,theburris bigger than the feature being machined. Tere are a variety of ways to minimize formation of burrs or remove them. Forsomeholes,runningthedrill through the hole more than once limits burr formation. Or, after a cross-hole is drilled, a pass with a turning tool across theholemouthcaneliminateburrs. Another alternative is to drill the hole in two steps, rst performing a predrill close to nish size, then nish drilling the hole tothenaldiameter.Tesecondpass takesoutminimalmaterialandleaves no burrs.Cross-holes and other features can be deburredwithnylonwheelsorbrushes engineered for use with hand-held tools. Applied in a live spindle in a Swiss-style machine, the brush will knock the burr o without scratching the part. Some shops adapt tiny dental burs to remove heavier burrs or make their own deburring tools. Inevitably,somefeaturesarepracti-cally impossible to deburr. In some cases, theburrjustopsbackandforthand never breaks away. Tis is common with titanium and some stainless steels. As a result, many shops EDM holes, especially those manufacturing medical parts that must be burr-free. Te additional process consumesmoretimeand makes the part more expen-sive,butitismandatedby therequirementforburr-free parts. In many cases, thermal, elec-trolytic or chemical deburring iseffective,butproblems arise when the burr is bigger thanapartfeatureorthe partitself.Acornerradius on a small medical part may be 0.005". Burning o the burr removes metal and can eradicate featuresor even blow up the whole part. In addition, when the amount of metal involved is so small, the process can be hard to control.Capturing and measuringIn addition to nding ways to handle theactualmachiningofmicroparts,an additionalchallengeiscapturingthe tinycomponents after machining and measuring them. Te standard collec-tionbasketsofscrew machines are generally too big for microparts. Ejected fromthesubspindle,apart can oat away or drop through the mesh in the bottom of the basket.Machinetoolbuilders offeravarietyofpart-handling systems. One method uses a vacuum extractor that sucks in the part as the subspindle releases it. Generating tiny features is one thing; conrming their dimensions is another. On-machinemeasurementgenerally isnotavailable,andpost-machining measurementusuallyinvolvesnoncon-tactvisionorshadowgraphtechniques. It is important to qualify the measuring system,aswellasthepeoplewhoare doing the measuring, to ensure measure-ment is consistently performed.No MysteryTe true keys to success in microma-chining with Swiss-style automatic lathes arepatienceandarealdesiretomake smallparts.Itissurprisinghowmany shopssimplydontwanttodealwith anything under " in diameter. It is essential to work carefully because the dimensions and tolerances involved leaveverylittlemarginforerror.On paper,thepartmayappeartoposeno problems,butthechallengesbecome obvious when part details cant be seen with the naked eye. Machining microparts on a Swiss-style machinecanbetedious,anditdoesnt always work the same way twice. Tere isaneedtomonitorandcontrolevery facet of the process, from the workpiece materialandworkholding/toolholding componentstothecuttingparameters and machine tool thermal stability.Tis type of machining usually comes downtotrial,errorandexperience. BuildersofSwiss-stylemachinesand tooling representatives can supply a great deal of practical information. Its their job to demystify the process and help shops facilitatetheproductionofmicroscale parts.About the authors: Glen Crews is Western regional sales manager for Marubeni-Citizen Cincom Inc., Allendale, N.J. He is based in the companys ofce in Fountain Valley, Calif. Telephone: (714) 434-6224. E-mail: gcrews@mcc-h-b.com. Bill Kennedy is a contributing editor to MICROmanufacturing. Telephone: (724) 537-6182. E-mail: billk@jwr.com. Swiss-style Success continuedMarubeni Citizen-CincomThis titanium screw for a medical application, produced on a Marubeni Citizen-Cincom R07 VI machine, typifies the continually shrinking scale of parts produced on Swiss-style machines. The 0.200"-long part has a 0.015"-dia. shank and features a 0.05"-dia. head with a 0.03"-dia. bore and four 0.02"-wide 0.03"-deep slots. Genevieve Swiss IndustriesTo be fully effective, tools for machining microscale parts on Swiss-type machines must be designed for that purpose. These boring bars are designed to handle minimum diameters from 0.480" to 0.027". Live spindles located perpendicular to the round bar stock enable Swiss-style CNC lathes to produce small square-sided parts like this titanium dental bridge.B. Kennedy micromanufacturing.com|33Adding a submersible rotary axis to a wire EDM, where a chuck mounted on a rotary table holds the workpiece rather than clamping ittothemachinesworktable,servesseveral purposes.Theseareparticularlyusefulfor producing microparts. EDMingunlikegrinding,turningor millingisanoncontactprocessandthere-fore doesnt exert side pressure on delicate part features,includingthosewithdiametersof 0.002"andsmaller.Tatenables,forexample, production of long, skinny parts. You would have a very hard time milling a shape with a 200:1 aspect ratio simply because the forces tend to deect the part, said Marcus Carius, a former dentist and owner of Implant Mechanix, a Vancouver, British Columbia, job shop that focuses on design, development and prototyping of dental devices. You dont have that with wire.Index, turn and spinIndexandburn,alsoknownasturnand burn, is the basic function a rotary EDM axis performs. Te EDM operator pushes the start button and the rotary table moves the workpiece to a specic location. When the table stops, the EDM head cuts the required feature while the partisstationarybeforebeingindexedtothe next location for further cutting, explained Peter Knowles, president of Hirschmann Engineering USA Inc., Schaumburg, Ill., a manufacturer of EDM rotary and tilting tables and other EDM products.A more sophisticated method is having the rotary axis interface with the control so the spark generator drives the rotary motionturn while burn,notedLarryWetmore,westernregion salesrepresentativeforEDMNetworkInc.,a Sugar Grove, Ill., EDM distributor and rebuilder. Tat enables the table to rotate simultaneously withanyotheraxismotioninacoordinated manner and allows the control to monitor the servo speed and rotary positioning and set the metal-removal parameters. An EDM is not like a mill, where you just give it a feed rate and it shoves the cutter through the material at that rate, Wetmore said. With an EDM, both sinker and wire, the control is always monitoringthecuttingactionandadjusting theservosandthesparkbasedoneachcut. Forexample,anEDMcontrolmightslowthe wire,orevenreverseitsdirection,ifthewire approaches a short-out situation.When the rotary axis external control inter-faces with a wire EDM via an M codewherein ithandshakeswiththemachine,allowing ittorunautomaticallyitisalsoreferredto asanA-orB-axis,Knowlesnoted.Havinga rotary axis integrate directly with the machine controleliminatestheexternalcontroland enablessynchronousmotion.Inthiscase,if youcanturnwhileburn,youcanindexand burn, he said.Whenintegratingarotaryaxisintoawire EDM,itsimportantthattheunithasalow prole so the machines upper and lower heads canbepositionedascloseaspossibletothe workpiece. Tis is necessary to achieve the tight tolerancestypicallyspeciedformicroparts andfeatures,explainedGisbertLedvon,busi-nessdevelopmentmanagerforEDMbuilder GF AgieCharmilles, Lincolnshire, Ill. Ledvon noted that the smallest wire it oers forturn-while-burnapplicationsis0.0008" Rotary BurnA rotary axis turns a wire EDM into a latheBy Alan Richte