xix CHAPTER 25 Cutting Tapers and Screw Threads on a Lathe................................................ 422 25.1 Taper Turning ..................................................424 25.2 Cutting Screw Threads on a Lathe ...................429 25.3 Safety.............................................................436 CHAPTER 26 Milling Machines ................................. 440 26.1 Types of Milling Machines ..............................442 26.2 Milling Categories ..........................................445 26.3 Milling Methods .............................................446 26.4 Milling Cutters ................................................446 26.5 Cutting Speeds and Feeds ..............................454 26.6 Workholding Attachments .............................456 26.7 Horizontal Milling Operations.........................459 26.8 Vertical Milling Machine Operations ...............466 26.9 Industrial Applications ...................................474 26.10 Milling Safety Practices ................................475 CHAPTER 27 Introduction to Computer Numerical Control and Automation....................... 478 27.1 Methods of Control .........................................480 27.2 Positioning Systems .......................................481 27.3 Movement Systems ........................................484 27.4 CNC Processing Equipment .............................487 27.5 Automation....................................................489 27.6 Flexible Manufacturing Systems ....................489 27.7 Safety .............................................................492 CHAPTER 28 Introduction to CNC Programming and Machining .................................... 496 28.1 Programming Methods ..................................498 28.2 CNC Programming Codes ................................502 28.3 CNC Modal Commands ...................................503 28.4 Planning the CNC Program .............................508 28.5 Writing the Program.......................................510 28.6 Setting Work Off sets and Tool Off sets .............515 28.7 Verifying the Program ....................................516 28.8 Running the Program.....................................517 28.9 Safety.............................................................518 CHAPTER 29 Nontraditional Machining Techniques .... 522 29.1 Electrical Discharge Processes ........................524 29.2 Electrochemical Machining ............................526 29.3 Chemical Machining.......................................527 29.4 Hydrodynamic Machining ..............................529 29.5 Electron Beam Machining ..............................530 29.6 Laser Beam Machining ...................................531 29.7 Ultrasonic Machining .....................................532 SECTION 5 WELDING CHAPTER 30 Soldering and Brazing ......................... 538 30.1 Soldering Conditions ......................................540 30.2 Tinning a Soldering Copper ............................542 30.3 Soldering a Lap Joint ......................................543 30.4 Soldering a Seam Joint ...................................543 30.5 Sweat Soldering a Joint ..................................544 30.6 Hard Soldering ...............................................544 30.7 Silver Brazing .................................................545 30.8 Safety.............................................................547 CHAPTER 31 Gas Welding ........................................ 550 31.1 Oxyfuel Gas Welding ......................................552 31.2 Gas Welding Equipment .................................554 31.3 Welding Rods .................................................557 31.4 Fluxes .............................................................558 31.5 Equipment Preparation and Adjustment ........558 31.6 Welding Joints ................................................559 31.7 Forehand Welding ..........................................561 31.8 Backhand Welding .........................................561 31.9 The Weld Pool.................................................561 31.10 Brazing and Braze Welding ..........................562 31.11 Gas Welding Safety Precautions ...................562