T.L.E. 4th quarter

• Mechanical Drafting is a program that prepares individuals to apply technical knowledge and skills to develop working drawings and electronic simulations in support of mechanical and industrial engineers, and related professionals
• Drafting


  The primary communication format for engineers
• Without drafting, engineers would not be able to communicate complex plans and design features to contractors and serviceability
• Drawing instruments used for drawing and designing purposes

  • T-Square
  • Triangle
  • Compass
  • Divider
  • Protractor
• T-square

  • It is a drawing instrument used when making horizontal lines
  • It is also used for guiding triangles when drawing vertical lines
  • It is made of wood, plastic, or a combination of both
  • There are three types: Fixed Head, Adjustable Head, and Detachable Head
• Triangle


  • It is a three-sided ruler, which typically has two equal sides meeting at a 90-degree angle and to a third side at 45, 30, including 60-degree angles
  • It is usually made of plastic and comes in different sizes
  • The base of the triangle must rest on the blade of the T-square
  • Drawing a line always starts from the point near the base going upward
  • Commonly used triangles are 30 degrees X 60 degrees and 45 degrees X 45 degrees
• Compass


  • It is used when drawing arcs and circles
  • It is used in a similar way to a divider
  • It is composed of one with the pen leg and the needlepoint leg being held together with a handle
• Divider


  • It is used when transferring measurements, dividing lines, and arcs into the desired number of equal parts
  • It can easily transfer accurate measurements by adjusting the divider points
• Protractor


  • It is a semi-circular instrument divided into 180 equal parts, each of which is called a degree
  • It is used to determine gradations of the degrees when measuring arcs, angles, and circles
  • A high-quality protractor is usually made of plastic
• Drawing tools and materials

  • Drawing paper
  • Masking tape
  • Pencil sharpener
  • Eraser
  • Drawing pencil
  • Triangular Scales
  • Erasing Shield
• Drawing paper


  Various types are available, but hard and soft surface drawing papers are highly recommended
• Masking tape


  Used for fastening the drawing paper on the drawing table or drawing board because it does not damage the board and it will not damage the paper if it is removed by pulling it off
• Pencil sharpener


  Pencils should be sharpened whenever they show signs of dullness
• Eraser


  A soft eraser is advantageous in removing smudges and pencil marks, whereas a harder eraser is useful for making changes and correcting errors in the drawing
• Drawing pencil

  • Comes in various grades, the grade to be used depends on the quality of the paper and the type of line work required
  • Hard pencils are used where extreme accuracy is required
  • Medium pencils are used for general purpose work
  • Soft pencils are too soft to be used in mechanical drafting, but very useful for artwork
• Triangular Scales


  • Used when reproducing a drawing in an enlarged or reduced form to some regular proportion
  • The architect's scale is the most used for general drawing
  • Its main function is to reproduce the measurements of an object in full size, reduced size, and enlarged size
• Erasing Shield


  Made up of metal with irregular holes, it is a useful tool to protect the rest of the drawing when clearing up smudges, unnecessary pencil lines, and other erasures
• Measuring instruments are identified correctly
• Measuring instruments are used as per their utilization
• Ruler


  Used to measure dimensions

  
• Scale


  Helps a drafter keep the proportions accurate
• Compass

  Used to draw circles, arcs, radii, and parts of many symbols
• Tape ruler

  Its main purpose is to reproduce, reduce or enlarge the dimension of size on a drawing
• Drafting Tools


  • Measuring Tools
  • Lining Tools
  • Testing Tools
• Ruler

  The most popular type of measuring tool, usually 6 or 12 inches in length, used for measuring sizes and distances

  
• Scale


  A type of measuring instrument used in general drawing, its main purpose is to reproduce the dimension in full size or to reduce or enlarge them on a drawing
• Triangle


  Used for drawing vertical and oblique lines
• 1. square


  Used as a guide in drawing horizontal lines and in measuring up to 48" straight line
• Divider


  Similar to a compass, used to split a distance into several equal parts
• Protractor


  Used for measuring and setting angles other than those obtainable with the triangles

  
• Tape measure


  A concave, spring-steel blade ranging from 1/4" to 1" wide and 6 to about 300 feet in length, coiled inside a carrying case, provides an easy means for accurately measuring curved surfaces
• Understanding of measurement is essential for all parts of manufacturing and production technology
• Measurements must be uniform so that people have a common understanding and application in the production and use of manufactured objects
• Measuring tools are used to measure dimensions, implementing any work with precision
• Drafting tools may be used for measurement and layout of drawings, or to improve the consistency and speed of creation of standard drawing elements
• Technical drawings, graphic images, and sketches can be created using a variety of instruments, ranging from traditional tools such as pencils, compasses, rulers, and a variety of triangles as well as by computer
• All measuring tools are precision tools and must be taken good care of to keep them in good shape to maintain their accuracy
• Technical drawing is essential for communicating ideas in industry and engineering
• To make the drawings easier to understand, people use familiar symbols, perspectives, units of measurement, notation systems, visual styles, and page layout
• Drawing tools may be used for the measurement and layout of the drawing. They include pens, pencils, rulers, compasses, protractors, and other drawing utilities