Layout Tools And Procedures

1. Layout Tools And Procedures Session 2

2. Laying Out • Process of scribing or marking center points, circles, arcs, or straight lines • Indicates shape of finished object • Amount of material to be removed • Position of holes to be drilled • Layouts made from an established baseline • Layouts of two types: basic and precision Shop Tools and Techniques

3. Layout Solutions • Layout very important to accuracy of finished product • Surface of metal coated with layout solution to make layout lines visible • Surface should be clean and free of grease • One primary type of solution available Shop Tools and Techniques

4. Types of Solutions • Layout dye or bluing • Most common • Available as a liquid or aerosol • Quick-drying, good sharp background • Layout cleaning solution available • Replaces dangerous solvents previously used Shop Tools and Techniques

5. Types of Solutions • Latex (White, Flat) Paint • Used for cast-iron castings • Easy to apply and easily covered with finish paint • Chalking • Mixture of lime and alcohol • Used for castings and hot-rolled steel • Readily clings to rough surface of castings Shop Tools and Techniques

6. Layout Tables and Surface Plates • Layout tables • Typically made of cast-iron • Allows use of layout machines • Often will accommodate even the largest of castings or weldments. Shop Tools and Techniques

7. Surface Plates • Work performed on surface plates (Granite or Cast-iron) • Granite considered better (Black, Pink, Gray) • Do not become burred • Do not rust • Are not affected by temperature change • Do not have internal stresses and therefore will not warp or distort • Are nonmagnetic • Can be used for checking near grinding machines • Are cheaper than similar-size cast-iron plate Shop Tools and Techniques

8. Care of Surface Plates • Keep working surface clean • Cover plate or table when it is not in use • Carefully place work on surface plate • Use parallels under workpiece whenever possible • Never hammer or punch any layout on surface plate • Remove burrs from cast-iron plates and protect surfaces with thin film of oil when not in use Shop Tools and Techniques

9. Scribers • Have hardened steel point(s) and on some one end bent at angle for hard-to-reach places • Point must always be sharp • Honed frequently on fine oilstone • Knife-edge scribers used for extremely fine lines Shop Tools and Techniques

10. Dividers and Trammels • Dividers used for scribing arcs and circles on layout and transferring measurements • Spring divider most common • Circles in sizes from 3 to 12 in • Adjustable Trammel • Consists of beam on which two sliding or adjustable heads with scriber points are mounted • Can do larger circles Shop Tools and Techniques

11. Hermaphrodite Calipers • One curved leg and one straight leg with scriber point • Used for laying out lines parallel to an edge and locating center round or irregular-shaped stock • For parallel lines holdscriber at 90º to edge Shop Tools and Techniques

12. Squares • Used to lay out lines at right angles to machined edge, test accuracy of surfaces that must be square, and set up work for machining • Adjustable squares - for general work • Solid square: beam and blade • Used where greater accuracy required • Master squares • Used to check accuracy of other squares Shop Tools and Techniques

13. Squares Shop Tools and Techniques

14. The Combination Set • Used extensively in layout work • Consists of steel rule, square head, bevel protractor and center head Shop Tools and Techniques

15. Shop Tools and Techniques

16. The Combination Set • Steel rule fitted to other three parts • Square head Used to lay out angles at 45º and 90º and parallel to edge lines • Bevel protractor used to lay out and check various angles (0º to 180º) • Accuracy is ± 0.5º • Center head forms center square when mounted on rule • Used for locating centers of ends of round , square, and octagonal stock Shop Tools and Techniques

17. Surface Gage Consists of base,spindle, and scriber Used on surface plate to scribeparallel lines Some have a V-groove machined in the base, which allows them to be used on cylindrical work Shop Tools and Techniques

18. Shop Tools and Techniques

19. Prick Punches and Center Punches • Difference only in angle of point • Prick punch ground to angle of 30º to 60º • Used to permanently mark location of layout lines • Center punch ground to 90º • Used to marklocation of centers of holes Shop Tools and Techniques

20. Layout Lines • After scribed on workpiece, are sometimes permanently marked by means of layout or prick-punch marks • Ensures layout line location visible should line be rubbed off through handling • Intersection of circle centerlines prick-punches then enlarge with center punch • Automatic center punches produces uniform spacing of marks Shop Tools and Techniques

21. Layout Accessories • Angle plate and toolmaker's clamp • Used when lines are required on face of plate • Possible to scribe intersecting 90º lines accurately Shop Tools and Techniques

22. Layout Accessories • Parallels • Used to raise work piece and maintain work surface parallel to top of surface plate Shop Tools and Techniques

23. Layout Accessories • 1-2-3 and 2-4-6 Blocks Shop Tools and Techniques

24. Layout Accessories • V-blocks • Used to hold round work for layout and inspection Shop Tools and Techniques

25. Layout Accessories • Keyseat rules and keyset clamps • Used to draw lines parallel to axis of shaft Shop Tools and Techniques