Contents Non-Traditional Machining Handbook Unit 1 1. Fundamentals of Non-Traditional Machining Unit 2 Wire EDM Fundamentals of Wire EDM

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1 9 Contents Non-Traditional Machining Handbook Testimonials...3 About the Author...4 Acknowledgments...8 Unit 1 1. Fundamentals of Non-Traditional Machining Understanding the Processes of Non-Traditional Machining...27 The Machining Revolution...29 The Two Phases of the Computer Revolution...29 A. Computer-controlled Machines:...29 B. Computer-controlled Machines Using Non-traditional Machining Methods...29 Six Basic Processes to Alter Material in Non-Traditional Machining...32 A. Electricity...32 B. Water...32 C. Abrasives...32 D. Chemicals...32 E. Plasma...32 F. Light...32 Speed and Accuracy...33 Understanding Accuracy...33 The Future...34 Unit 2 Wire EDM 2. Fundamentals of Wire EDM Revolutionizing Machining...39 Wire EDM Beginnings...40 Production Wire EDM...41 Capabilities of Wire EDM...42 Wire EDM a Serious Contender With Conventional Machining...42 New Demands by Design Engineers...43 Fully Automated Wire EDMs...44 How Wire EDM Works...45 The Step by Step EDM Process...47 A. Power Supply Generates Volts and Amps...47 B. During On Time Controlled Spark Erodes Material...47 C. Off Time Allows Fluid to Remove Eroded Particles...48 D. Filter Removes Chips While the Cycle is Repeated...48 Super Precision Band Saw...49

2 10 Non-Traditional Machining Handbook Independent Four Axis...50 Understanding Independent Four Axis...52 Submersible Cutting...53 Staying Competitive Profiting With Wire EDM Users of Wire EDM...55 Benefits Of Wire EDM...55 A. Production Runs...55 B. Various Shapes and Sizes...56 C. Accuracy and Finishes...56 D. Eliminates Extra Machining Processes...56 E. Burr Free and Perfectly Straight Machining...57 F. Damaged Parts Can Be Repaired with Inserts...57 G. Less Need for Skilled Craftspersons...58 H. Material Hardness Not a Factor...58 I. Computers Can Perform Calculations...58 J. Digitizing is Possible...59 K. Miniaturization of Parts...60 L. Machining With Nozzles Away from Workpiece...60 Parts for Wire EDM...61 A. Precision Gauges and Templates...61 C. Shaft Slots...62 D. Collets...62 E. Parting Tubes and Shafts...63 F. Shaft Pockets...63 G. Fabrication of Graphite Electrodes for Ram EDM...63 I. Progressive Stamping Dies...64 K. Molds...65 L. Special and Production Tool Cutters...65 M. Difficult-to-Machine Shapes...66 N. Other Cost-Reducing Parts...66 Cutting Shim Stock Absolutely Burr Free...68 Single Cavity Cut With Wire EDM Into One Side of a Tube...69 Horizontal Wire EDM...70 Machining Costs Proper Procedures for Wire EDM Starting Methods for Edges and Holes...71 Three Methods to Pick Up Dimensions A. Pick Up Two Edges as in Figure 4: B. Pick Up a Hole as in Figure 4: C. Pick Up an Edge and Holes or Two Holes as in Figure 4: Edge Preparation...72 A. Square Edges Machined or Ground....72

3 Contents 11 B. Scale...73 C. Pick-Ups...74 Starter Holes...74 A. Automatic Pick-up...74 C. Relieved Holes...75 D. Smooth Holes...75 E. Placement and Location of Starter Holes...76 Layout Understanding the Wire EDM Process Accuracy and Tolerances...79 Finishes...79 Wire Path...80 A. Wire Kerf...80 Skim Cutting...81 A. Barreling Effect and Wire Trail-Off...82 B. Metal Movement...83 C. Finishes and Accuracy...83 Carbide...84 Polycrystalline Diamond...84 Ceramics...85 Flushing...85 Cutting Speed...86 Impurities...86 Recast and Heat-Affected Zones...87 AC Non-Electrolysis Power Supplies...87 Isolated Pitting...88 Heat-Treated Steels...89 Cutting Large Sections...89 Cutting Sections From a Block...90 A. Leaving a Frame...90 B. Strength of Frame...91 C. Material for Clamping...91 Understanding the Wire EDM Process Reducing Wire EDM Costs Create One Slug...93 Keeping Flush Nozzles on the Workpiece...95 Machining After Wire EDM...96 Cutting Multiple Plates and Sheet Metal Parts...97 Production Lots...98 Stipulating Wire Sizes...99 Pre-Machining Non-Complicated Shapes...100

4 12 Non-Traditional Machining Handbook 7. Wire EDM Applications Production Wire EDM...97 A Great Problem...99 Examples of Wire EDM...99 A. Tall Parts...99 B. Modified Machines Submersible Cutting C. Large Heavy Gears D. Various Tall Parts E. Overhanging Parts F. Long Tubes G. Other Applications Splitting Machined Parts Cutting a Test Specimen Advantages of Wire EDM for Die Making A. Old-Fashioned Tool and Die Making B. The Revolution C. Advantages of Wire EDM Dies One-Piece Die Sections Exact Spare Parts Dowel Holes EDMed Better Tool Steels Accuracy Die Repairs Fine Textured Finish Eliminates Distortion Inserts for High Wear Areas Smaller Dies Longer Lasting Punches and Dies From One Piece of Tool Steel Cutting Stripper and Die Section Together Wave of the Future Unit 3 Ram EDM 8. Fundamentals of Ram EDM Ram EDM Machining Ram EDM Beginnings How Ram EDM Works The Step-by-Step Ram EDM Process Polarity No-Wear Fuzzy Logic Fumes from Ram EDM Benefits of Understanding the Process...124

5 Contents Profiting With Ram EDM Uses of Ram EDM Benefits of Ram EDM A. Different Shapes and Sizes B. Accuracy and Finishes C. Workpiece Hardness Not a Factor D. EDMing Threads Into Hardened Parts A. Molds B. Blind Keyways E. Helical Gear Machining Micro Machining for Ram EDM Machining Large Pieces Materials for Ram EDM Speeding the Mold Processing EDMing Carbide Proper Procedures for Ram EDM Ram EDM Electrodes and Finishing Electrodes A. Function of the Electrode B. Electrode Selection C. Type of Electrode Materials D. Galvano Process for Metallic Electrodes E. Custom Molded Metallic Electrodes F. Graphite Electrodes H. Electrode Wear I. Abrading Graphite Electrodes I. Ultrasonic Machining for Graphite Electrodes J. Wire EDMing Metallic and Graphite Electrodes K. Electrodes and C Axis H. Electrode Overcut Recast and Heat-Affected Zone Finishing Mirror Finishing and Diffused Discharge Machining Micro Machining Dielectric Oil and Flushing for Ram EDM Dielectric Oil Coolant System Flash Point Flushing A. Proper Flushing B. Volume, Not Pressure C. Types of Flushing...151

6 14 Non-Traditional Machining Handbook 1. Pressure Flushing a. Pressure Flushing Through the Electrode b. Pressure Flushing Through the Workpiece Suction Flushing Combined Pressure and Suction Flushing Jet Flushing Pulse Flushing a. Vertical Flushing b. Rotary Flushing c. Orbiting Flushing Filtration System The Challenge of New Procedures Reducing Costs for Ram EDM Preparing Workpieces for Ram EDM Difference Between Ram and Wire EDM in Reducing Costs Prolonging Electrode Life With No-Wear EDMing and No Premachining Electrode and Workpiece Holding Devices Orbiting Manual Machines Mounted With Orbiting Devices Repairing Molds With Microwelding Abrasive Flow Machining Automatic Tool Changers Future of Ram EDM Unit Small Hole EDM Drilling How Small Hole EDM Drilling Works A. Dielectric and Flushing Pressure B. The Electrode C. Electrode Guides D. Servo Motors Metal Disintegrating Machines Compared to Small Hole EDM Drilling 179 Other Methods to Produce Holes Disadvantages in Small Hole EDM Drilling A. Electrode Wear B. Reduced Speed for Large Holes C. Blind Holes are Difficult to Control Advantages in EDM Drilling A. Drilling on Curved and Angled Surfaces B. Drilling Hardened Materials C. Materials That Produce Chips that Cling to Cutters D. Drilling Deep Holes E. No Hole Deburring F. Preventing Broken Drills...181

7 Contents 15 G. Creating Straight Holes Accuracy of Small Hole EDM Drilling Versatility of Small Hole EDM Drilling Conclusion Unit Abrasive Flow, Thermal Energy Deburring, and Ultrasonic Machining Abrasive Flow Machining A. How Abrasive Flow Machining Works B. Abrasives C. Viscosity D. Extrusion Pressure E. Finishes Thermal Energy Deburring Disadvantages and Advantages of Thermal Energy Deburring Ultrasonic Machining and Polishing How Ultrasonic Machining Works Conclusion Unit Photochemical Machining Fundamentals of Photochemical Machining Designing the Part Imaging Etching and Stripping Materials and Products for Photochemical Machining Tolerances Corner Radii Beveling Cutting and Etching in One Operation Three Dimensional Chemical Machining Disadvantages of Photochemical Machining A. Bevel Slots and Holes B. High Run Production C. Limited Metal Thicknesses Advantages of Photochemical Machining A. Eliminates the Need for Hard Tooling B. Just In Time Machining C. Freedom of Burrs D. Stress-Free Machining E. Delicate and Complex Parts Can be Produced Photochemical Machining of Micro-Etched Screens Electroformed Process for Micro-Etched Screens Conclusion...211

8 16 Non-Traditional Machining Handbook Unit Electrochemical Machining How Electrochemical Machining Works Disadvantages of Electrochemical Machining A. The Shaped Workpiece is Not a Replica of the Electrode B. Shaped Electrodes are Difficult to Machine C. Electrolyte and Sludge Removal Advantages of Electrochemical Machining A. Practically No Electrode Wear B. No Recast Layer or Thermal Stress C. Material Hardness and Toughness Not a Factor D. Rapid Metal Removal E. Deburring and Radiusing of Holes Stem Drilling Capillary Drilling Conclusion Unit Plasma and Precision Plasma Cutting How Plasma Cutting Works Plasma Processes A. Conventional Plasma Cutting B. Dual Gas Plasma Cutting C. Water Shield Plasma Cutting D. Water Injection Plasma Cutting E. Precision Plasma Cutting Difference Between Regular Plasma and Precision Plasma Cutting A. Beveled Cuts B. Double Arcing Materials for Plasma Cutting Heat Distortion and Heat Affected Zone Accuracy Consumables Plasma and Shield Gases Advantages and Disadvantages of Plasma Cutting Systems Plasma and Turret Punch Presses Other Applications for Plasma Understanding Plasma Cutting...235

9 Contents 17 Unit Waterjet and Abrasive Waterjet Machining Fundamentals of Waterjet and Abrasive Waterjet Machining Introducing Abrasive Into the Waterjet Abrasives for Cutting The Abrasive System The Abrasive Cutting Head Motion Control Systems Catcher System Profiting With Waterjet and Abrasive Waterjet Cutting Materials Cut With Waterjet Materials Cut With Abrasive Waterjet Accuracy Safety Disadvantages of Waterjet and Abrasive Waterjet Machining A. Frosting From Abrasive Waterjet Cutting B. Slower Speed Rates and Higher Costs Than Plasma and Lasers..253 C. Catchers Needed With Multi-Axis Cutting D. Large Cuts Become Stratified Advantages of Waterjet and Abrasive Waterjet Machining A. Material Savings B. No Special Tooling Required C. Moisture Absorption Not a Problem D. Focusing the Waterjet is Not Critical E. Simple Fixtures Required F. Entry Hole Not Required G. No Heat Affected Zone or Microcracking H. No Fumes I. Eliminates Some Difficult Cutting Problems J. Burr Free Cutting K. Easily Attached to Robots Cutting With Multiple Heads and Stacking Materials Glass Sculpturing Turning With Abrasive Waterjet Waterjet and Abrasive Waterjet Capabilities...256

10 18 Non-Traditional Machining Handbook Unit 10 Lasers 20. Fundamentals of Lasers Lasers: The Revolutionary Concept Laser Cutting How Lasers Work Resonator Laser Mirrors Laser Optics Assist Gases The Laser Cut Sensing Unit Laser Safety Fumes From Laser Cutting Understanding Laser Cutting Kerf Width Material Distortion Heat-affected Zone Edge Quality Test Cuts Reducing Costs Speed of Lasers Tolerances Surface Condition Beam Quality Beam Focal Length Quantity Redesigning Parts Lasers and Turret Punch Presses Cutting Laser Increasingly in Demand Various Lasers and Their Configurations How YAG Lasers Work Increasing Power for Nd:YAG Lasers Various Lasers Benefits of Nd:YAG Lasers Fiber Optics Smaller Focusing Beam Excimer Lasers How Excimer Lasers Work Capabilities of Excimer Lasers...280

11 Contents 19 Optical Microlithography Laser for Integrated Circuits Traveling Methods of Laser Cutting Machines Beam Traveling Workpiece Traveling Combination of Beam and Workpiece Traveling Custom-Made Laser Systems Beam Splitting Profiting With Laser Cutting Materials for Laser Cutting Determining Factors on Material Thickness Lacquered Metals Tube Cutting Multiaxis Laser Cutting Lasers With Pallet Changers or Sheet Loaders Lasers With Robots Part Trimming Time Sharing Advantages of Laser Cutting Material Savings Minimum Heat-Affected Zone Edge Quality Minimum Distortion and Thermal Stress Close Nesting of Parts Thin Webs Elimination of Hard Tooling Just-In-Time (JIT) Machining Various Shapes and Sizes Material Hardness Consistent Laser Beam Prototypes Can be Fabricated Easily Repeatability Ideal for Short Run Production Disadvantages of Lasers Lasers for Welding, Cladding, Alloying, Heat Treating, Marking, and Drilling I. Laser Welding A. Laser Welding Compared to Electron Beam Welding B. Two Types of Laser Welding: Spot and Continuous Welding C. Welding Dissimilar Metals D. Keyhole Welding E. Focusing the Beam and Through-The-Lens TV Viewer F. Considerations for Laser Welding...305

12 20 Non-Traditional Machining Handbook II. Laser Cladding A. Conventional Cladding B. Advantages of Laser Cladding III. Laser Surface Alloying A. Lasers the Ideal Tool for Surface Alloying B. Difference Between Laser Alloying and Laser Cladding IV. Laser Heat Treating A. Procedures for Laser Heat Treating B. Advantages and Disadvantages of Surface Heat Treating V. Laser Marking A. How Laser Marking Works B. Advantages of Laser Marking VI. Laser Drilling A. How Laser Drilling Works B. Disadvantages of Laser Drilling C. Advantages of Laser Drilling The Future of Lasers Unit Rapid Prototyping and Manufacturing The Photopolymer Rapid Prototyping Process A. Computer Aided Design B. Laser Drawing C. Photopolymerization D. Translator E. Sweep and Z-Wait F. Postcuring G. Finishing H. Size Capabilities Selective Laser Sintering The 3D Keltool Process Solid Ground Curing Fused Deposition Prototyping Multi-Jet Modeling Prototyping The ProMetal Process Advantages of Office Modeling Systems Expanding Field of Manufacturers and Methods Understanding the Rapid Prototyping and Manufacturing Process Advantages of Rapid Prototyping and Manufacturing A. Eliminates Time-Consuming and Costly Model Making B. Fast Turnarounds C. Redesigned Models Easily Produced...335

13 Contents 21 D. Enhanced Visualization for Design Verification E. Rapid Prototyping and Investment Casting F. Producing Hard Tooling With Rapid Prototyping Rapid Milling for Prototypes New Developments Conclusion Unit Purchasing Equipment Staying Abreast With New Technology Benefits of Purchasing Equipment Making the Right Selection A. Selecting the Right Process B. Selecting the Right Machine Various Machines and Their Cutting Capabilities* A. Wire EDM B. Laser (1500 watt CO 2 ) C. Precision plasma (70 amp) D. Abrasive water jet Choosing the Brand of Machine A. Service B. Capability C. Reliability of Company Retrofitting or Building a Machine Factors in Purchasing Equipment A. Can the machine process the material? B. Does the process meet accuracy requirements? C. Is the surface finish satisfactory? D. Does the process affect the material, for example: unsatisfactory... heat affected zone, surface cracks, or burrs? E. Is this the most cost effective method? F. In the long term, is this the best process for various operations?..348 G. Which manufacturer has the best and most reliable equipment?..348 H. What is the financial health of the company? I. Does the machine manufacturer have excellent service and sufficient spare parts inventory in case of machine breakdowns? J. What are the initial as well as the additional costs associated with having this equipment in house? K. Does the company really need to invest in this machine, or would... it be wiser to invest the money to enhance other machining... operations? (This issue will be discussed in the next chapter.) Machine Installation Decision Making...349

14 22 Non-Traditional Machining Handbook Unit Outsourcing Advantages of Job Shops A. Competitive Outsourcing B. Guaranteed Quality C. Reliable Service D. Efficiencies of Job Shops Costs to be Considered For In-House Work A. Fixturing and Machine Modification B. Programming and Inspecting Equipment C. Training Personnel D. Costly Support Equipment E. Cost of Unused Machines Due to Economic Slowdown F. Machine Maintenance G. Machine and Operation Costs The Final Decision Maximizing Core Competency Unit The Revolutionary Future Non-Traditional Machine The Problem Possible Solutions A. Develop an intensifier that will use a magnetic field to spin and accelerate electrons with plasma B. Use a magnetic field with high-intensity laser light C. Have a high-energy magnetic field to guide plasma or laser D. Create a powerful laser wave length that will not diffuse E. Combine high-energy light, plasma, and electricity F. Use controlled atomic energy G. Apply star wars technology for cutting Conclusion Unit Questions Chapter 1 Fundamentals of Non-Traditional Machining Chapter 2 Wire EDM Fundamentals Chapter 3 Profiting With Wire EDM Chapter 4 Proper Procedures for Wire EDM Chapter 5 Understanding the Wire EDM Process Chapter 6 Reducing Wire EDM Costs Chapter 7 Various Wire EDM Applications Chapter 8 Fundamentals of Ram EDM...371

15 Contents 23 Chapter 9 Profiting With Ram EDM Chapter 10 Ram EDM Electrodes and Finishing Chapter 11 Dielectric Oil and Flushing for Ram EDM Chapter 12 Reducing Costs for Ram EDM Chapter 13 Fast Hole EDM Drilling Chapter 14 Abrasive Flow, Thermal Energy Deburring, and Ultrasonic Machining Chapter 15 Photochemical Machining Chapter 16 Electrochemical Machining Chapter 17 Plasma and Precision Plasma Cutting Chapter 18 Waterjet and Abrasive Waterjet Machining Chapter 19 Profiting With Waterjet and Abrasive Waterjet Cutting Chapter 20 Fundamentals of Lasers Chapter 21 Understanding Laser Cutting Chapter 22 Various Lasers and Their Configurations Chapter 23 Profiting With Laser Cutting Chapter 24 Lasers for Welding, Drilling, Cladding, Alloying, Heat Treating, Marking, and Drilling Chapter 25 Rapid Prototyping and Manufacturing Chapter 26 Understanding the Rapid Prototyping and Manufacturing Process Chapter 27 Purchasing Equipment Chapter 28 Outsourcing Chapter 29 The Revolutionary Future Non-Traditional Machine Index Index...389

16 24 Non-Traditional Machining Handbook Notes