Machinery's Handbook 27th Edition TABLE OF CONTENTS THREADS AND THREADING SCREW THREAD SYSTEMS METRIC SCREW THREADS 1725 Screw Thread Forms 1783 American Standard Metric Screw 1725 V-Thread, Sharp V-thread Threads M Profile 1725 US Standard Screw Thread 1783 Comparison with Inch Threads 1725 Unified Screw Thread Forms 1783 Interchangeability 1726 International Metric Thread 1783 Definitions 1727 Definitions of Screw Threads 1784 Basic M Profile 1784 M Crest and Root Form UNIFIED SCREW THREADS 1785 General Symbols 1732 American Standard for Unified 1785 M Profile Screw Thread Series Screw Threads 1785 Mechanical Fastener Coarse Pitch 1732 Revised Standard 1786 M Profile Data 1732 Advantages of Unified Threads 1787 Limits and Fits 1732 Thread Form 1793 Dimensional Effect of Coating 1733 Internal and External Screw 1793 Formulas for M Profile Thread Design Profile 1797 Tolerance Grade Comparisons 1733 Thread Series 1797 M Profile Limiting Dimension 1734 Inch Screw Thread 1798 Internal Metric Thread 1735 Diameter-Pitch Combination 1800 External Metric Thread 1736 Standard Series Combinations 1804 American Standard Metric Screw 1763 Coarse-Thread Series Threads MJ Profile 1764 Fine-Thread Series 1804 Diameter-Pitch Combinations 1764 Extra-Fine-Thread Series 1807 Trapezoidal Metric Thread 1765 Constant Pitch Series 1807 Comparison of ISO and DIN 1766 4-Thread Series Standards 1767 6-Thread Series 1813 Trapezoidal Metric Thread 1768 8-Thread Series 1814 ISO Miniature Screw Threads 1769 12-Thread Series 1814 British Standard ISO Metric Screw 1770 16-Thread Series Threads 1771 20-Thread Series 1814 Basic Profile Dimensions 1772 28-Thread Series 1815 Tolerance System 1773 Thread Classes 1815 Fundamental Deviations 1773 Coated 60-deg. Threads 1816 Tolerance Grades 1775 Screw Thread Selection 1816 Tolerance Positions 1775 Pitch Diameter Tolerance 1816 Tolerance Classes 1775 Screw Thread Designation 1817 Lengths of Thread Engagements 1776 Designating Coated Threads 1817 Design Profiles 1776 Designating UNS Threads 1817 Designation 1776 Hole Sizes for Tapping 1818 Fundamental Deviation Formulas 1776 Minor Diameter Tolerance 1819 Crest Diameter Tolerance 1777 Unified Miniature Screw Thread Formulas 1777 Basic Thread Form 1819 Limits and Tolerances 1778 Design Thread Form 1822 Diameter/Pitch Combinations 1779 Design Form Dimensions 1822 Limits and Tolerances for 1779 Formulas for Basic Dimensions Finished Uncoated Threads 1780 Limits of Size and Tolerances 1823 Diameter/Pitch Combinations 1781 Minimum Root Flats 1824 Comparison of Various Metric 1782 British Standard Unified Screw Thread Systems Threads UNJ Profile 1824 Comparison of Maximum Metal Dimension 1721 Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition TABLE OF CONTENTS THREADS AND THREADING ACME SCREW THREADS WHITWORTH THREADS 1825 General Purpose Acme Threads 1857 British Standard Whitworth (BSW) 1825 Acme Thread Form and Fine (BSF) Threads 1827 Acme Thread Abbreviations 1857 Standard Thread Form 1827 Designation 1857 Whitworth Standard Thread Form 1827 Basic Dimensions 1857 Tolerance Formulas 1827 Formulas for Diameters 1858 Basic Dimensions 1827 Limiting Dimensions 1827 Single-Start Screw Thread Data PIPE AND HOSE THREADS 1827 Pitch Diameter Allowances 1860 American National Standard Pipe 1827 Multiple Start Acme Threads Threads 1832 Pitch Diameter Tolerances 1860 Thread Designation and Notation 1832 Centralizing Acme Threads 1860 Taper Pipe Thread 1834 Basic Dimensions 1861 Basic Dimensions 1836 Formulas for Diameters 1862 Engagement 1836 Limiting Dimensions 1862 Tolerances on Thread Elements 1836 Screw Thread Data 1863 Limits on Crest and Root 1836 Pitch Diameter Allowances 1864 Pipe Couplings 1837 Pitch Diameter Tolerances 1864 Railing Joint 1837 Tolerances and Allowances 1864 Straight Pipe Threads 1843 Designation 1864 Mechanical Joints 1843 Acme Centralizing Thread 1866 Dryseal Pipe Thread 1843 Stub Acme Threads 1866 Limits on Crest and Root 1843 Basic Dimensions 1866 Types of Dryseal Pipe Thread 1843 Formulas for Diameters 1866 Limitation of Assembly 1843 Limiting Dimensions 1868 Tap Drill Sizes 1846 Stub Acme Thread Designations 1868 Special Dryseal Threads 1846 Alternative Stub Acme Threads 1869 Limitations for Combinations 1846 Former 60-Degree Stub Thread 1869 British Standard Pipe Threads 1848 Square Thread 1869 Non-pressure-tight Joints 1848 10-Degree Square Thread 1870 Basic Sizes BUTTRESS THREADS 1870 Pressure-tight Joints 1871 Limits of Size 1849 Threads of Buttress Form 1872 Hose Coupling Screw Threads 1849 British Standard Buttress Threads 1872 ANSI Standard 1849 Lowenherz or Löwenherz Thread 1873 Hose Coupling Threads 1850 Buttress Inch Screw Threads 1874 Screw Thread Length 1850 American National Standard 1874 Fire Hose Connection Buttress Inch Screw Threads 1875 Basic Dimensions 1850 Pitch Combinations 1876 Limits of Size 1850 Basic Dimensions 1850 Buttress Thread OTHER THREADS 1850 Symbols and Form 1877 Interference-Fit Threads 1851 Buttress Thread Tolerances 1878 Design and Application Data 1851 Class 2 Tolerances 1879 External Thread Dimension 1855 Allowances for Easy Assembly 1879 Internal Thread Dimension 1855 External Thread Allowances 1880 Engagement Lengths 1856 Buttress Thread Designations 1881 Allowances for Coarse Thread 1856 Designation Sequence 1881 Tolerances for Coarse Thread 1722 Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition TABLE OF CONTENTS THREADS AND THREADING OTHER THREADS MEASURING SCREW THREADS (Continued) (Continued) 1882 Variations in Lead and Diameter 1905 Checking Pitch Diameter 1883 Spark Plug Threads 1905 Checking Thread Thickness 1883 BS Spark Plugs 1906 Wire Sizes 1883 SAE Spark Plugs 1906 Checking Thread Angle 1884 Lamp Base and Socket Threads 1907 Best Wire Diameters 1885 Instrument and Microscope 1909 Taper Screw Threads Threads 1910 Buttress Threads 1885 British Association Thread 1911 Thread Gages 1886 Instrument Makers’ Screw Thread 1911 Thread Gage Classification 1886 Microscope Objective Thread 1911 Gages for Unified Inch Threads 1889 Swiss Screw Thread 1914 Thread Forms of Gages 1890 Historical and Miscellaneous 1914 Thread Gage Tolerances 1890 Aero-Thread 1916 Tolerances for Cylindrical Gages 1890 Briggs Pipe Thread 1918 Formulas for Limits 1890 Casing Thread 1891 Cordeaux Thread TAPPING AND THREAD 1891 Dardelet Thread CUTTING 1891 “Drunken” Thread 1919 Selection of Taps 1891 Echols Thread 1921 Tap Rake Angles 1891 French Thread (S.F.) 1921 Cutting Speed 1891 Harvey Grip Thread 1921 Tapping Specific Materials 1892 Lloyd & Lloyd Thread 1924 Diameter of Tap Drill 1892 Lock-Nut Pipe Thread 1925 Hole Size Limits 1892 Philadelphia Carriage Bolt Thread 1933 Tap Drill Sizes 1892 SAE Standard Screw Thread 1934 Tap Drills and Clearance Drills 1892 Sellers Screw Thread 1934 Tolerances of Tapped Holes MEASURING SCREW THREADS 1935 Hole Sizes before Tapping 1936 Miniature Screw Threads 1893 Measuring Screw Threads 1937 Tapping Drill Sizes 1893 Pitch and Lead of Screw Threads 1937 ISO Metric Threads 1893 Thread Micrometers 1938 Clearance Holes 1894 Ball-point Micrometers 1939 Cold Form Tapping 1894 Three-wire Method 1940 Core Hole Sizes 1895 Classes of Formulas 1941 Tap Drill Sizes 1895 Screw Thread Profiles 1941 Removing a Broken Tap 1895 Accuracy of Formulas 1941 Tap Drills for Pipe Taps 1896 Best Wire Sizes 1941 Power for Pipe Taps 1897 Measuring Wire Accuracy 1942 High-Speed CNC Tapping 1897 Measuring or Contact Pressure 1943 Coolant for Tapping 1897 Three-Wire Formulas 1943 Combined Drilling and Tapping 1898 NIST General Formula 1944 Relief Angles for Cutting Tools 1899 Formulas for Pitch Diameters 1946 Lathe Change Gears 1899 Effect of Small Thread Angle 1946 Change Gears for Thread Cutting 1901 Dimensions Over Wires 1946 Compound Gearing 1901 Formula Including Lead Angle 1946 Fractional Threads 1902 Measuring Whitworth Threads 1947 Change Gears for Metric Pitches 1903 Buckingham Exact Formula 1947 Change Gears for Fractional 1904 Accuracy of Formulas Ratios Acme and Stub Acme Thread 1723 Copyright 2004, Industrial Press, Inc., New York, NY Machinery's Handbook 27th Edition TABLE OF CONTENTS THREADS AND THREADING TAPPING AND THREAD THREAD MILLING CUTTING (Continued) (Continued) 1965 Change Gears for Helical Milling 1948 Quick-Change Gearbox Output 1965 Short-lead Milling 1950 Finding Accurate Gear Ratios 1965 Helix 1950 Lathe Change-gears 1966 Helix Angles 1951 Relieving Helical-Fluted Hobs 1967 Change Gears for Different Leads 1977 Lead of Helix THREAD ROLLING 1980 Change Gears and Angles 1952 Thread-Rolling Machine Determining Helix Angle 1952 Flat-Die Type 1981 For Given Lead and Diameter 1952 Cylindrical-Die Type 1982 For Given Angle 1952 Rate of Production 1982 For Given Lead 1953 Precision Thread Rolling 1982 And Lead Given DP and Teeth 1953 Steels for Thread Rolling 1982 Lead of Tooth Given Pitch Radius 1953 Diameter of Blank and Helix Angle 1953 Automatic Screw Machines SIMPLE, COMPOUND, 1954 Factors Governing the Diameter DIFFERENTIAL, AND BLOCK 1954 Diameter of Threading Roll INDEXING 1954 Kind of Thread on Roll 1955 Application of Thread Roll 1983 Milling Machine Indexing 1955 Thread Rolling Speeds and Feeds 1983 Hole Circles THREAD GRINDING 1983 Holes in Brown & Sharpe 1983 Holes in Cincinnati 1957 Thread Grinding 1983 Simple Indexing 1957 Wheels for Thread Grinding 1984 Compound Indexing 1957 Single-Edge Wheel 1985 Simple and Compound Indexing 1958 Edges for Roughing and Finishing 1990 Angular Indexing 1958 Multi-ribbed Wheels 1990