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Engineering Drawing. Sketching Skills GSMST. Objectives. Tips and Techniques Lettering Patience and practice needed. Sketching. Although most final drawings are computer generated, initial and freehand sketches are vital to the design process
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Engineering Drawing Sketching Skills GSMST
Objectives • Tips and Techniques • Lettering • Patience and practice needed
Sketching • Although most final drawings are computer generated, initial and freehand sketches are vital to the design process • Freehand does not mean messy. Sketches should display an adequate amount of detail, and any pertinent notes/comments pertaining to the drawing • For instance, if a line is supposed to be straight, make it as straight as possible. A square will not pass for a circle.
Sketching • Sketching is a rapid, freehand method of drawing without the use of drawing instruments. Sketching is also a thinking process and a method of communication.
Sketching • This is not artistic sketching, but technical sketching • Emphasis will be on sketching geometric figures to represent features of objects • Medium grade pencils work best for sketching • All lines should be dark enough to standout from the page
Engineering Drawing Rules • Always use a Pencil. • Make all lettering the same size. • Use Engineering or Drafting Paper.
Pencil Techniques • The best pencil for lettering on most surfaces are the H, F, and HB grades. • Hold your pencil in the position shown. It should make approximately a 60o angle with the paper.
Pencil Lead Designation • Note: Reverse order below
Sketching Tips: General • Relax and draw in a direction comfortable to you • Mark end points of the lines to be sketched and draw between them • Draw long lines as a series of short ones • Use grid paper when available • Follow sketching and text conventions • Do NOT use a straight edge to draw lines!
Sketching Tips Sketching straignt lines does not mean they have to look like they are machine drawn.
Sketching Tips: Construction Lines • Use construction lines • Begin by drawing bounding boxes with construction lines • Make construction lines much lighter and thinner than finished lines • Identify the major features and overall dimensions • Leave construction lines on the sketch
Drawing Circles • Two methods for sketching circles • Box in diameter and mark radius • Draw center-point lines and mark radius
Sketching Tips: Miscellaneous • Do not shade the drawing – this is not pencil sketching • Title information is required • Keep views aligned (very important) • Draw neat circles – change page orientation if needed
Sketching techniques • Use very light construction lines • “Box in” the rough outline of the object • Darken only the lines you wish to keep • Clean up the edges and rough spots
Box In Technique • Boxing in the outer dimensions is often the first step in producing a sketch
Sketching Tips • If you don’t have a ruler, you can estimate dimensions using your pencil when sketching • Always keep your pencil at arms length. Why?
Sketching Tips • Layout of drawing using your pencil for dimensional reference
Lettering • The style of engineering lettering we will use in this course is Single Stroke Gothic Lettering • An example of the characters is shown on drawing numbers 1 and 2 • Notice that only capital letters are demonstrated, since we will use only capital letters on drawings
Lettering Notes • Lettering Guidelines – Handout • Lettering Styles • Shape of Letters • Order of Drawing Lines • Character Uniformity • Spacing