1. Sketching
Design & Drafting
Unit 4

2. Purposes of Sketching
Preliminary approach to a problem before going to the expense of making an instrument drawing
To give the drafter a better picture of the object to be drawn
For recording notes and technical information in the shop or field for future use in the drafting department
As an aid to “think through” the solution to an engineering-type problem

3. Rules in Sketching A scale is not required
Sketches are drawn in proportion
Small objects are sketched larger than their normal size
Freehand lines are rough, not rigid
Line contrast should be used
A soft pencil should be used
Finished linework should be dark and conform to line alphabet standards
Sketches are dimensioned the same as machine drawings

4. Steps in Completing a Drawing
Select necessary views
Block in lightly the shape of the object
Block in details in each view
Erase unwanted construction lines
Darken lines