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Mount Royal University – Department of Math, Physics, & Engineering
ENGR 1271
DRAWING
CLASS 8
MARCH 9, 2012
Outline
 Review of dimensioning standards and practices
 Dimensioning three-dimensional drawings
Drawing Homework (Due in class 9) - Dimensioning a Pictorial Drawing
Using a scale of at least 1:1, redraw the object assigned in class as both a three-view
multiview drawing and an isometric drawing. Assume that the measurement grid
behind the cavalier oblique drawing of the assigned object is a 10 x 10 x10 millimetre
grid. Completely dimension both the multiview and isometric drawings following
engineering practices for proper dimensioning. Do not over dimension. Include the
scale, units of measure, third angle symbol for the multiview, and all necessary
dimensioning symbols.
Marking Criteria for Drawing Homework (40 marks)
 Multiview drawings are correct
 Multiview drawings are arranged correctly
 Isometric drawing is correct
 Proportions are correct
 Dimensions for isometric drawing are placed in the correct
three-dimensional plane
 Dimensions are placed according to proper dimensioning practices
(.5 will be deducted for each extraneous dimension)
 Extension lines are correct
 Dimension lines are correct
 Dimension line spacing is correct
 Dimension numbers are correct
 Dimensioning symbols are correct
 Leader lines are correct
 Arrows are correct
 Scale and units of measure are indicated correctly
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Dimensioning Test on Blackboard (10 marks)
Complete the ten questions on the “Hot Spot” test posted on Blackboard. Each
question contains a dimensioned, multiview drawing with one poorly placed and/or
unnecessary dimension. Choose and click on the redundant dimension number in
each question. The test can be saved as you work on it but you can only submit it
once. Submit the test before 9:30 am, Thursday, March 16, 2012.
Reading Review
Chapter 6, “Dimensioning and Tolerancing”, pages 415-421, Engineering Design and
Communication 1, Dym and Leake.
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