STEREOLITHOGRAPHY AND SELECTIVE LASER SINTERING p 36 SURFACE PREP FOR ADHESIVES p 40 DIODES AND HOW THEY EMIT LIGHT p 48 APRIL 2015 machinedesign.com BY ENGINEERS FOR ENGINEERS Supersonic FFlight THE RETURN OF 30 p| Powered by Penton® First we raised the bar Then we lowered the price You’ve known Rittal quality in Wallmount Enclosures for years Now you can get the industry’s highestquality enclosures at a price so low Hoffman and Saginaw can’t bear for you to see With more than 100 UL Listed standard sizes available in both carbon and stainless steel, and features like foamedin-place gasket and secure locking systems on every enclosure, Rittal Wallmounts are ideal for all industrial needs And, with our manufacturing plant located in the USA, local availability means you won’t have to wait for the perfect Rittal Wallmount enclosure you need for your facility today Wallmounts Rittal Part # WM121206NC WM161208NC WM161608NC WM201608NC WM202008NC WM242008NC WM242408NC Size 12x12x6 16x12x8 16x16x8 20x16x8 20x20x8 24x20x8 24x24x8 Rittal Part # JB060604HC JB100806HC JB121206HC Size 6x6x4 10x8x6 12x12x6 Hoffman Part # CSD12126 CSD16128 CSD16168 CSD20168 CSD20208 CSD24208 CSD24248 Saginaw Part # SCE-12EL1206LP SCE-16EL1208LP SCE-16EL1608LP SCE-20EL1608LP SCE-20EL2008LP SCE-24EL2008LP SCE-24EL2408LP Rittal Price $93 $105 $120 $122 $131 $149 $145 Saginaw Part # SCE-606ELJ SCE-10086ELJ SCE-1212ELJ Rittal Price $24 $40 $51 Starting at $24 Junction Boxes and Wallmounts include a mounting panel at no extra charge Junction Boxes Hoffman Part # A606CHNF A10086CHNF A1212CHNF For a full list of available enclosures and participating dealers, please visit www.rittalenclosures.com Terms and conditions subject to change Get the FREE Wallmount App for iOS and Android www.RittalEnclosures.com (800) 477-4000 RITTAL SHIPS QUICK! Made in the USA APRIL 2015 | VOLUME 87, ISSUE In This Issue FEATURES 30 SUPERSONIC FLIGHT: OVERCOMING THE SONIC BOOM NASA and private companies are pushing research to reintroduce supersonic flight to the aerospace market 36 WHAT’S THE DIFFERENCE BETWEEN SLA AND SLS? Depending on the application, one must weigh the pros and cons of a liquid- or powder-based approach to optimize 3D printing 40 30 PROPER SURFACE PREP: AN ADHESIVE’S BEST FRIEND To get the strongest, more durable adhesive bonds, start with clean surfaces 48 THE ABCs OF LEDs The integration of LEDs into a myriad of lighting applications not only saves energy costs, but the environment from carbon dioxide, too 50 THE EVER-SHRINKING LIMITATIONS OF 3D PRINTING Limitations and developments are changing the way engineers think about of 3D printing 58 PRACTICAL ASPECTS OF WELD FATIGUE In the last of this series, we look at some real-world cases of applying fatigue data to welded structures NEWS 14 DEPARTMENTS SATELLITES HITCH A RIDE ON A FIGHTER JET COLUMNS EDITORIAL ON MACHINEDESIGN.COM 10 LETTERS 12 WHAT’S INSIDE Quarter-turn Fasteners Prevent Lost Hardware The Value of Innovation When You’re Under the Knife—Kenneth Korane 24 INTERVIEW 40 Pallets Move on Customizable Conveyor The Changing World of Brake Design— Manfred Meyer 72 PRODUCT DEVELOPMENT Test Suite Rebalancing Reduces Time-to-Market— Bradford L Goldense DISTRIBUTION RESOURCE 62 PRODUCTS 66 70 71 71 NEW PRODUCTS DATA FILES CLASSIFIEDS AD INDEX FASTENERS GO HIGH-TECH 50 ON THE COVER: The Supersonic Aerion AS2 from Aerion Corp JOIN US ONLINE twitter.com/machinedesign facebook.com/ MachineDesignMagazine Printed in U.S.A., Copyright © 2015 Penton Media, Inc All rights reserved MACHINE DESIGN (ISSN 0024-9114) is published monthly by Penton Media, Inc., 9800 Metcalf Ave., Overland Park, KS 66212 Paid subscriptions include issues 1-12 Rates: U.S.: $139/year; $199/two years Canada/ Mexico: $159/year; $239/two years; All other countries: $199/year; $299/two years Cost for back issues are U.S $10.00 per copy plus tax, Canada $15.00 per issue plus tax, and Int’l $20.00 per issue OEM Handbook and Supplier Directory, $50.00 plus tax Prepaid subscription: Penton Media (MACHINE DESIGN), P.O Box 2100, Skokie IL 60076-7800 Periodicals postage paid at Kansas City, MO and additional mailing offices Can GST #R126431964 Canadian Post Publications Mail Agreement No.40612608 Canada return address: IMEX Global Solutions, P.O Box 25542, London, Ont., N6C 6B2 Digital subscription rates: U.S.: $69/year Canada/Mexico: $79/year All other countries: $99/year Print/Digital combo subscription rates: U.S.: $174/year; $249/two years Canada/Mexico: $199/year; $299/two years; All other countries: $249/year; $374/two years POSTMASTER: Send change of address notice to Customer Service, MACHINE DESIGN, P.O Box 2100, Skokie, IL 60076-7800 APRIL 2015 MACHINE DESIGN Protect your gear at AutomationDirect prices! Ensure that your equipment is safeguarded at every point in the power distribution network with high-quality, cost-efective circuit protection and disconnection devices that meet UL standards They’ll pay for themselves in no time! UL 489 MCCBs starting at $182 SUPPLY Motor feeder short circuit and ground fault protection UL 98 UL 489 Miniature Circuit Breakers, up to 40A starting at $18.00 UL 98 Disconnect Switches starting at $88 • Class T, RK5, RK1 and Class J current limiting short circuit protection up to 600A • Sold in packs of 1, or 10 fuses • • • • • Non-fusible and fusible rotary disconnect switches • Make/break loads up to 800 amps Main Circuit UL 248 Current Limiting Fuses starting at $7.75 (Class T 1-pack) Motor disconnecting means • Rated current up to 800A, max 600V • Standard and high-interrupting capacity types (NEC 430.101-430.113) Motor branch-circuit short circuit protection DIN-rail mounted Up to 40 amps 1, 2, or 3-pole available 10kAIC @ 277/480VAC (NEC 430.51-430.58) (NEC 430.21-430.44) C Motor overload protection C UL 508 (NEC 430.81-430.91) OL Motor Circuit Motor controller OSHA Lockout/ tagout disconnect (NEC 430.81-430.91) M MOTOR Bryant Manual Motor Controllers starting at $23.50 UL 508 Load Switches starting at $26 • • • • • • 35mm DIN rail mountable or direct mountable • Loads from 16 to 125 amps • IP20 degree of protection Lockout / Tagout capability 30, 40 and 60A up to 600 VAC 2-pole and 3-pole switches Quick make, slow break design UL Listed as “Suitable as Motor Disconnect” under UL 508 Relays Control Circuit PLC I/O Contact Coils • Up to 30A, utilizing Class CC or Midget fuses • 1, and 3-pole models • Open fuse indication • Lockout/Tagout capability UL 248 General Fuses starting at $2.00 (5-pack) UL 1077 Supplementary Protectors starting at $9.00 Control Transformer UL 98 and UL 508 Compact Fusible Disconnect Switches starting at $19.50 • DIN rail mountable • Full line of auxiliary switches, alarm switches and padlock lockout accessories • B trip curve to 60 amps • C trip curve 0.5 to 60 amps • D trip curve 0.5 to 40 amps • Class CC, general purpose class M (Midget) and small dimension glass and ceramic fuses • Ideal supplementary protection up to 30 amps for branch circuits and 50 amps for end of line equipment Research, price, buy at: www.automationdirect.com/circuit-protection Order Today, Ships Today! * See our Web site for details and restrictions © Copyright 2014 AutomationDirect, Cumming, GA USA All rights reserved 1-800-633-0405 the #1 value in automation on METAL HARDWARE COATINGS AND FINISHES ECOCAR CHALLENGE TO IMPROVE HYBRID CARS http://machinedesign.com/metals/basics-coatings-and-finishesmetal-hardware http://machinedesign.com/automotive/ecocar-3-challengesstudents-industry-partners-improve-hybrid-cars Engineers have a range of coatings and finishes they can specify for metal hardware such as retaining rings, wave springs, latches, hinges, and fasteners The finishes can be functional or aesthetic Here is a list of the most popular coating and finishes The EcoCAR challenge, sponsored by General Motors and the U.S Department of Energy, features the most technologically advanced Camaro and tasks the team with creating an energy-efficient powertrain to maximize performance Students’ focus is on choosing alternate fuels and advanced technologies to lower greenhouse gases and tailpipe emissions The design must keep the original body design, and preserve safety and consumer standards join us online twitter.com/machinedesign facebook.com/MachineDesignMagazine WHY INTERLOCK GUARDS TRUMP LOCKOUT/TAGOUT MYTHS ABOUT THE R&D TAX CREDIT http://machinedesign.com/blog/8-myths-about-rd-tax-credit http://machinedesign.com/basics-design/engineering-basicswhy-interlock-guards-trump-lockouttagout Here’s a look at some of the reasons why interlocked safety guards prevent more accidents than lockout/tagout procedures and rules The U.S R&D tax credit could be worth up to $10 billion annually to small and large firms Yet evidence shows that only one of out of 20 small and medium-sized companies eligible for this credit actually use it Why is that? Our Skeptical Engineer, Steve Mraz, takes a look at the reasons APRIL 2015 MACHINE DESIGN Smarter Embedded Designs, Faster Deployment The combination of NI LabVIEW system design software and reconfigurable I/O (RIO) hardware helps small design teams with varied expertise develop demanding embedded applications in less time Using this graphical system design approach, you can take advantage of the same integrated platform to program embedded processors and FPGAs for faster application development in industries ranging from energy to transportation, manufacturing, and life sciences >> Accelerate your productivity at ni.com/embedded-platform 800 453 6202 ©2013 National Instruments All rights reserved LabVIEW, National Instruments, NI, and ni.com are trademarks of National Instruments Other product and company names listed are trademarks or trade names of their respective companies 12118 LabVIEW system design software offers ultimate flexibility through FPGA programming, simplifies code reuse, and helps you program the way you think–graphically Self-lubricating dry-tech bearings ® Improve technology Reduce cost April 2015 Delivered in business days! General purpose Editorial ExEcutivE Editor: Kenneth J Korane ken.korane@penton.com SEnior Editor: Stephen J Mraz stephen.mraz@penton.com tEchnology Editor: CarloS Gonzalez carlos.gonzalez@penton.com tEchnology Editor: Jeff KernS jeff.kerns@penton.com contEnt Production dirEctor: MIChael Browne michael.browne@penton.com contEnt Production SPEciAliSt: roGer enGelKe roger.engelke@penton.com Production Editor: JereMy Cohen jeremy.cohen@penton.com ASSociAtE contEnt ProducEr: IlIza SoKol iliza.sokol@penton.com ASSociAtE contEnt ProducEr: leah SCully leah.scully@penton.com industry covEragE: Extreme loads FAStEning & Joining, PAckAging, mAnuFActuring: Stephen J Mraz Fluid PoWEr, mEchAnicAl: Kenneth J Korane motion control, cAd/cAm: CarloS Gonzalez 3d Printing, mAtEriAlS, ElEctronicS/ElEctricAl: Jeff KernS art dEpartmEnt Art dirEctor: randall l ruBenKInG randall.rubenking@penton.com grouP dESign dirEctor: anthony VItolo tony.vitolo@penton.com contEnt dESign SPEciAliSt: JIM MIller jim.miller@penton.com production Low wear grouP Production dirEctor: Carey Sweeten carey.sweeten@penton.com Ad oPErAtionS SPEciAliSt: Brenda wIley brenda.wiley@penton.com audiEncE markEting High temperature uSEr mArkEting dirEctor: Brenda roode brenda.roode@penton.com uSEr mArkEting mAnAgEr: deBBIe Brady debbie.brady@penton.com FrEE SubScriPtion/StAtuS oF SubScriPtion/AddrESS chAngE/miSSing bAck iSSuES: hAllmArk dAtA T | 847.763.9670 F | 847.763.9673 machinedesign@halldata.com onlinE Product dEvEloPmEnt dirEctor: ryan MaleC ryan.malec@penton.com cliEnt SErvicES mAnAgEr: Joann MartIn joann.martin@penton.com salEs & markEting Chemical resistant mAnAging dirEctor: traCy SMIth T | 913.967.1324 F | 913.514.6881 tracy.smith@penton.com regional sales rePresenTaTiVes Ak, AZ, cA, co, hi, id, iA, ky, mn, mt, nd, nE, nv, or, Sd, tn, ut, WA, Wi, Wy, WEStErn cAnAdA: paul MIlnaMow paul.milnamow@penton.com t | 312.840.8462 f | 913.514.3957 dc, dE, md, nc, nJ, ny, oh, PA, Sc, vA, Wv: Brandy BISSell brandy.bissell@penton.com t | 234.678.8401 f | 913.514.6357 Food contact ct, mA, mE, nh, ri, vt, EAStErn cAnAdA: lIz Stott, liz.stott@penton.com t | 857.636.9737 f | 913.514.6914 il, in, mi, cEntrAl cAnAdA: Marty McClellan marty.mcclellan@penton.com T | 312.840.8488 M | 312.343.9278 Al, Ar, Fl, gA, kS, lA, mo, mS, nc, nm, ok, Sc, tx: CarrIe halBrooK carrie.halbrook@penton.com t | 317.358.9965 f | 913.514.3965 Niche products inTernaTional sales rePresenTaTiVes bElgium, FrAncE, luxEmburg, nEthErlAndS, PortugAl, ScAndinAviA, SPAin, unitEd kingdom: raChel dISanto rachel.disanto@husonmedia.com t | 011.44.1625.876622 M | 011.44.7794.366887 gErmAny, AuStriA, And SWitZErlAnd: ChrIStIan hoelSCher christian.hoelscher@husonmedia.com t | 011.49.89.95002778 f | 011.49.89.95002779 itAly: CeSare CaSIraGhI cesare@casiraghi,info t | 011.390.31.261407 f | 011.390.31.261380 JAPAn, ASiA: helen laI helen@twoway-com.com t | 866.2.2727.7799 f | 866.2.2727.3686 Special solutions Longer life Shipped from stock Online calculations Online 3D CAD Cost down life up! dEsign EnginEEring & sourcing group vicE PrESidEnt & mArkEt lEAdEr: BIll BauMann grouP dirEctor oF EditoriAl contEnt And uSEr EngAgEmEnt: nanCy frIedrICh grouP dirEctor oF oPErAtionS: ChrIStIna CaVano grouP dirEctor oF mArkEting: Jane Cooper pEnton chiEF ExEcutivE oFFicEr: daVId KIeSelSteIn david.kieselstein@penton.com chiEF FinAnciAl oFFicEr: nICola allaIS nicola.allais@penton.com SEnior vP, dESign EnginEEring grouP: BoB MaCarthur bob.macarthur@penton.com 1166 AvEnuE oF thE AmEricAS, 10th Floor nEW york, ny 10036 t | 212.204.4200 Free samples available! 800-521-2747 Electronic Design | Machine Design | Microwaves & RF | Medical Design | Source ESB | Hydraulics & Pneumatics | Global Purchasing | Distribution Resource Power Electronics | Defense Electronics | Electronic Design Europe | Engineering TV com/iglide April 2015 machine design We Turn Ideas Into Results Advanced Material Technologies Every day at Minnesota Rubber and Plastics we produce high performance components and assemblies for the most demanding applications Our experience in advanced material formulation enables us to meet increasingly stringent regulations and your unique product requirements Our over 60 year history in the design and manufacture of Custom Molded Rubber, Plastics and Assemblies complex devices makes us the preferred partner for industry leaders throughout the world The next time your component or assembly project seems impossible, there’s no one better to partner with than Minnesota Rubber and Plastics We’ll make your tough application a reality For a project evaluation call : 952-927-1400 Email requests to power@mnrubber.com Download our complete literature and design guide at mnrubber.com/power Leader in Advanced Material Technologies Editorial Kenneth Korane | Executive Editor The Value of Innovation When You’re Under the Knife L Application Example: SUV rear window latch assembly utilizes three Coiled Pins as hinges ongtime readers of Machine Design may have noticed my comments and articles have been missing from our magazine and website for the last six months Many of you likely assumed that I was serving a stint in the Big House, but the truth is a bit more lame: I’ve been out on medical leave The good news: After innumerable encounters with doctors, nurses, and technicians of every stripe and tests and procedures ad infinitum, the medical professionals overseeing my care finally managed to pinpoint my problem and permanently correct it The bad news: A foray into the healthcare system isn’t cheap, to say the least The cost of a hospital room can exceed $5,000/day; CT and MRI scans easily run in the $2,000 to $3,000 range; and even a single aspirin costs over $3 With insurance, there’s sticker shock Without it, you could be bankrupt With so much hand-wringing over rising medical costs, one certainly wonders: Given all of today’s medical bells and whistles, the benefits of advanced technologies outweigh the costs? If you’re sick, they often Take heart procedures Options for treating heart attacks now range from bypass surgery, angioplasty, and stents to defibrillator implants and pacemakers, to name a few Treatment costs have gone up with the introduction of such procedures, but they bring savings in terms of shorter hospital stays, quicker recovery, and fewer re-admissions, in addition to a longer and better-quality life An even better example of cost-benefit tradeoffs involves infant mortality In 1950, little could be done medically for low-birthweight babies (weighing less than 3.3 lb) and the mortality rate was a shocking 70% And those lucky enough to survive could expect a shorter lifespan as well as life-long medical and developmental problems Now, with advances such as NICUs, special ventilators, and medications that speed lung development, four out of five low-birthweight infants survive Such treatments are undoubtedly expensive But that’s far outweighed by the tangible and sizable financial and societal benefits when these once-sick infants grow up, earn a paycheck, and enjoy normal, productive lives Or consider surgical robots These engineering wonders combine high-definition vision and imaging systems with precision-guided medical instruments and let surgeons perform complicated procedures with only a few small incisions They can also cost well over $1 million apiece But in the hands of skilled specialists, surgical robots can be more productive with higher success rates and fewer complications, compared to more invasive alternatives They tend, for the patient, to result in less pain, faster recovery, and an overall less unpleasant experience For bean counters that may not matter, but for someone on the operating table, it sure has a lot of value At the end of the day, investments in the latest medical technology outweigh the costs? From a patient’s perspective, they’re worth every penny April 2015 machinE dEsign ... ABOUT THE R&D TAX CREDIT http://machinedesign.com/blog/8-myths-about-rd-tax-credit http://machinedesign.com/basics -design/ engineering-basicswhy-interlock-guards-trump-lockouttagout Here’s a look... HYBRID CARS http://machinedesign.com/metals/basics-coatings-and-finishesmetal-hardware http://machinedesign.com/automotive/ecocar-3-challengesstudents-industry-partners-improve-hybrid-cars Engineers... Part # SCE-12EL1206LP SCE-16EL1208LP SCE-16EL1608LP SCE-20EL1608LP SCE-20EL2008LP SCE-24EL2008LP SCE-24EL2408LP Rittal Price $93 $105 $120 $122 $131 $149 $145 Saginaw Part # SCE-606ELJ SCE-10086ELJ