Some Dimensioning Techniques Used in Machine drawing
1. No dimension should be assumed, calculated or directly measured from drawing.
4. In orthographic views, dimensions should be given logically .Dimensions should be distributes in three views logically and equally in all views.
5. Dimensions lines should be placed at least 8 mm, away from outlines and from each other.
8. For a numbers of dimensions, they should be given in a progressive manner i.e. in increasing order as given in fig.
9. When a number parallel dimension lines are to be drawn, they are shown staggered as shown in fig.
10. Arrowheads should ordinarily be drawn within the limits of dimensioned features. But when the space is too narrow, they may be placed outside as shown in fig.
11. Dimensions of cylindrical parts should as far as possible in the views in which they are seen as rectangles .The dimensions indicating a diameter should be followed by a symbol as shown in below fig.
12. When there are of small holes, their diameters should be given by a notes as shown in figure
13. Angular dimensions may be shown by one of the method shown.
14. Countersunk and threading are shown as below.
15. Symbols for methods of projection must be shown on drawings.
Introduction to Seals : Oil under pressure is moving in every hydraulic circuit. Since oil is a liquid it has the tendency to 'leak' through every gas/slot it finds during movement. This leakage of...
Introduction to Slotting Machine : The slotter or slotting machine is also a reciprocating type of machine tool similar to a shaper. It may be considered as a vertical shaper. The machine operates...