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Design and Technology. Marking and Measuring Tools. Steel Rule. It is used for measuring, marking and testing flatness. It is usually graduated in both inches and millimeters. Zero end design is used for setting gauges and measuring internal size
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Design and Technology Marking and Measuring Tools
Steel Rule • It is used for measuring, marking and testing flatness. • It is usually graduated in both inches and millimeters. • Zero end design is used for setting gauges and measuring internal size • The common size we use in the workshop is 300mm long. Longer steel rule such as 600mm and 1000mm are also available for large workpieces.
Engineer’s Square • Try square is for woodwork while Engineer’s square is for metalwork. • They are for marking and testing right angles. • They are also used to test squareness and check the internal and external angles of a workpiece.
Scriber • It is used for marking lines on a metallic, or plastic surfaces. • It is always used with a try square or steel rule for marking straight lines. • Chalk or pigment can be added on the surface before marking in order to show th lines more clearly.
Design and Technology Cutting Tools
Engineer’ Vice • It is commonly used in metalwork for filing or sawing. • It is also called Mechanic’s Vice.
Vice Clamp • Soft metal or plastic vice clamp are used to protect the workpiece from scratching.
Hacksaw • It is used for making straight cuts in metal and plastic materials.
Hacksaw • The blade with the teeth pointing forward is held tightly by a wing nut. • The blade can also be rotated to suit different sawing works.
Hacksaw • Hold the work in the vice and keep the cut line vertical and close to the jaws to prevent vibration. • In cutting long workpieces, the saw blade should be turned 90º to the frame.
Coping Saw • It is used for sawing curves in thin wood, plastics and soft metal. • The saw teeth must be pointing towards the handle to avoid breakage. • The blade can be turned for sawing along long wood pieces.
Safety Notes • Check whether the blade is secured firmly. • Do not touch the cut edge as it is very hot and the sharp burr may hurt your fingers.
Files • Files are used for shaping and smoothing metal and hard plastics.
Files • Files with various teeth cuts, lengths, cross-sections and coarseness of teeth can be chosen for different works.
Files • 1. Crossfiling • It is mainly for rough cutting which does not leave a smooth surface.
Files • 2. Drawfiling • It is to remove crossfiling marks to obtain a smooth surface.
Files • Supporting the work • Clamp the work with the vice with part of it above the jaws.
Files • Holding the File • heavy general light
Files • Filing • Use the full length of the file. • Press the file evenly to cut across the whole surface. • Test the flatness and squareness of the workpiece frequently.
Files • Other situations • Before filing convex or concave curves, cut the workpiece to the approximate shape.
Wire Brush • Cleaning the File • Remove the tiny metal chips in the file by brushing across the file with a file card.
