Copyright © Texas Education Agency, 2012. All rights reserved. Engineering Graphics Basic Drafting Facts and Tools Copyright © Texas Education Agency, 2012. All rights reserved.
What is the difference between Freehand & Drafting? Essentially the difference is that when you are sketching freehand, you ONLY use a pencil and your hand. The minute you use a tool like a triangle, you are drafting, because a tool helps you draw things more precisely. 2 Copyright © Texas Education Agency, 2012. All rights reserved.
How many views does every object have? They are six (6) views we could draw, but we only draw three (3). Top, Front, & Right Side. We will cover these more in depth later. 3 Copyright © Texas Education Agency, 2012. All rights reserved.
Copyright © Texas Education Agency, 2012. All rights reserved. We draw oblique pictorials, of which the front view angle is 900 and the sides are 450. Cabinet = Full depth Cavalier = ½ depth We will cover these more in depth later 4 Copyright © Texas Education Agency, 2012. All rights reserved.
Copyright © Texas Education Agency, 2012. All rights reserved. We draw isometric pictorials in which all of the views are drawn at 300. We will cover these more in depth later 5 Copyright © Texas Education Agency, 2012. All rights reserved.
Different lines we could draw. There actually many more, these are just the basics. We will cover these more in depth later. 6 Copyright © Texas Education Agency, 2012. All rights reserved.
Drafting Tools & The Uses 7 Copyright © Texas Education Agency, 2012. All rights reserved.
Copyright © Texas Education Agency, 2012. All rights reserved. Straight Edge Guides Purpose is to line up drawings and keep everything square. Drafting Arm Parallel Bar T Square 8 Copyright © Texas Education Agency, 2012. All rights reserved.
Copyright © Texas Education Agency, 2012. All rights reserved. Templates Ellipse Template Quickly and accurately draw objects that are drawn often. There are MANY more, each for it’s own use. Examples: architectural, landscape, electronics, etc. Circle Templates 9 Copyright © Texas Education Agency, 2012. All rights reserved.
Copyright © Texas Education Agency, 2012. All rights reserved. Drawing Mechanical Pencils: for drawing, use the .5mm for all general work. Use the .7mm for darker or finished work. .5mm is the “work horse”keep all lines light until you are finishing it up. Eraser Shield is for erasing parts of the drawing. It will help keep you from erasing the parts that are correct. Lettering Guide is used to create guide lines for lettering. Mechanical Pencils (2) .5mm & .7mm Eraser Shield AMES Lettering Guide 10 Copyright © Texas Education Agency, 2012. All rights reserved.
Copyright © Texas Education Agency, 2012. All rights reserved. Irregular Curves Used to help draw circular items. Examples: ellipses, cycloids, etc. Flexible Curve French Curves 11 Copyright © Texas Education Agency, 2012. All rights reserved.
Copyright © Texas Education Agency, 2012. All rights reserved. Clean Up Tools Used to erase mistakes. Used to clean off your drawing & work station. NEVER use just your hand to clean up or you will smear the lead! Eraser Brush ALWAYS clean up behind yourself! Leave the station as clean, or cleaner, than when you used it! 12 Copyright © Texas Education Agency, 2012. All rights reserved.
Copyright © Texas Education Agency, 2012. All rights reserved. Layout Tools Bow Compass Compass is used to draw precise circles, arc, etc. Can also be used to help layout marks. Divider is used to get precise measurements, & transfer measurements. Divider 13 Copyright © Texas Education Agency, 2012. All rights reserved.
Copyright © Texas Education Agency, 2012. All rights reserved. Triangles 30/60 Triangle “Tall & Skinny” Used to draw perfectly square lines with the straight edges tools. Each has the most commonly used angles required. When combined, they can get you all of the other angles you might need. 600 300 45 Triangle “Short & Fat” 450 450 14 Copyright © Texas Education Agency, 2012. All rights reserved.
Copyright © Texas Education Agency, 2012. All rights reserved. Drafting Scales Used to draw objects precisely or exactly. Engineers: deals primarily with inches and based on 10 “parts”. Architectural: deals with feet & inches. 16 is regular ruler. All other the fractions represent a foot or 12”. Metric based on MM & 10 “parts”. Refer to lessons on Scales for more information. 15 Copyright © Texas Education Agency, 2012. All rights reserved.
Engineering Scale Video
Copyright © Texas Education Agency, 2012. All rights reserved. Summary You need to know your tools and how to correctly use them. Yes, Auto CAD is the most used tool, but you must understand how the process works. Then, you’ll become a better drafter. Also, very often you maybe called upon to draw something with no computer around, so you will be better prepared if you know these tools and how to use them. 17 Copyright © Texas Education Agency, 2012. All rights reserved.