1. Dimensioning Ø 8 FACING Ø14 X 3 DEEP 80 50 45 40° 13 20 40 Working document Linguistic review 29-09-07 Technical drawings must not only faithfully reproduce the shape of objects, but also serve as a guide to their construction or manufacturing. Dimensioning an object means giving all the necessary dimensions to build a technical object.

2. Dimensioning Ø 8 FACING Ø14 X 3 DEEP 80 50 45 40° 13 20 40

3. 36 Dimensioning To enter dimensions and specify their place we use a fine line, called a dimension line, ending in arrows. The extension line is a fine line that connects the measured part of the object to the dimension line. Lines The dimension is placed in the center of the dimension line. Its value is given in millimetres. Units are not shown.

4. Dimensioning approx. 1 mm The dimension line touches the extension line. The extension line does not touch the object. approx. 2 mm The extension line extends past the dimension line. approx. 10 mm approx. 10 mm The distance between the object and the dimension line or between two dimension lines is about 10 mm. Drawing the dimensions

5. Dimensioning approx. 1 mm The dimension line touches the extension line. The extension line does not touch the object. approx. 2 mm The extension line extends past the dimension line. approx. 10 mm approx. 10 mm The distance between the object and the dimension line or between two dimension lines is about 10 mm. Drawing the dimensions

6. Dimensioning Dimensioning includes two stages: The first defines the general shapes of the object by means of size quotations. Overall size quotations show the greatest dimensions of the object by length, width and height.

7. Dimensioning Dimensioning includes two stages: The first defines the general shapes of the object by means of size quotations. Overall size quotations show the greatest dimensions of the object by length, width and height.

8. The second stage is used to specify the placement of different parts of the object by means of position quotations. Dimensioning

9. The second stage is used to specify the placement of different parts of the object by means of position quotations. Dimensioning

10. Basic rules for dimensioning If possible, group all dimensions between or above views. Place the dimension where the shape best describes the object.

11. Dimensioning Basic rules for dimensioning If possible, group all dimensions between or above views. Place the dimension where the shape best describes the object.

12. Dimensioning Basic rules for dimensioning In a series of dimensions, one of the ends of the series is not quoted. Place the shortest dimension lines close to the object to be measured.

13. Dimensioning Basic rules for dimensioning In a series of dimensions, one of the ends of the series is not quoted. Place the shortest dimension lines close to the object to be measured

14. Dimensioning Basic rules for dimensioning Do not quote on hidden feature lines. If necessary, quote outside the views. Line up position quotations.

15. Dimensioning Basic rules for dimensioning Do not quote on hidden feature lines. If necessary, quote outside the views. Line up position quotations.

16. Dimensioning Dimensioning cylindrical shapes Objects with rectangular shapes are dimensioned differently than those with cylindrical shapes. The shapes of rectangular objects are dimensioned in relation to surfaces. Round or cylindrical shapes are located in relation to their center.

17. Dimensioning Dimensioning cylindrical shapes Objects with rectangular shapes are dimensioned differently than those with cylindrical shapes. The shapes of rectangular objects are dimensioned in relation to surfaces. Round or cylindrical shapes are located in relation to their center.

18. Dimensioning Dimensioning cylindrical shapes Ø 25 DIA 25 Ø 20 R18 The leader line may be drawn at 30º, 45º or 60º. The line touches the circle and points to the center. The Ø symbol or abbreviation DIA precedes the diameter to be dimensioned. Curves composed of arcs of a circle are dimensioned by their radius. Cylindrical holes are dimensioned by a note specifying the diameter and depth, if necessary.

19. Dimensioning Dimensioning cylindrical shapes Ø 25 DIA 25 Ø 20 R18 The leader line may be drawn at 30º, 45º or 60º. The line touches the circle and points to the center. The Ø symbol or abbreviation DIA precedes the diameter to be dimensioned. Curves composed of arcs of a circle are dimensioned by their radius. Cylindrical holes are dimensioned by a note specifying the diameter and depth, if necessary.

20. 80 50 45 Ø 8 FACING Ø14 X 3 DEEP 40° 13 20 40 Dimensioning Shape dimension Position dimension Extension line Leader line Dimension Dimension line Summary

21. Dimensioning 80 50 45 Ø 8 FACING Ø14 X 3 DEEP 40° 13 20 40 Shape dimension Position dimension Leader line Dimension Dimension line Summary

22. Dimensioning example for an object that includes cylindrical shapes R18 R7 R5 Ø5 - 2 HOLES R5

23. Dimensioning example for an object that includes cylindrical shapes R18 R7 R5 Ø5 - 2 HOLES R5

24. Dimensioning Ø 8 FACING Ø14 X 3 DEEP 80 50 45 40° 13 20 40 Working document Bibliography GIESECKE, Frederick E., MITCHELL, Alva, SPENCER, Henry Cecil, HILL, Ivan Leroy, GYGDON, John Thomas et NGUYEN, Dinh N. « Dessin technique », Montréal, Éditions du Renouveau Pédagogique inc., 1982, 769 p. JENSEN, C.H. « Dessin industriel », Montréal, McGraw- Hill, 1972, 752 p. STIRLING, Norman. « Éléments de dessin industriel », Montréal, HRW, 1979, 372 p.