1. Example of auxiliary view

2. Projections including auxiliary view

3. PRIMARY AUXILIARY VIEW
Primary auxiliary view (on a plane perpendicular to one of the principle planes) TV
AUXILIARY PLANE
PRIMARY AUXILIARY VIEW
TOP
Fold line,
Reference line, Reference axis
FRONT FV SV
Exact dimensions and shape can be seen without any calculations
Plane is rotated about the line of intersection
Q. Auxiliary plane is perpendicular to which principal plane and at an angle (other than 90o) to which principal plane ?

4. AUXILIARY VERTICAL PLANE (AVP)- (perpendicular to HP, at an angle to VP)
Auxiliary Front View
Auxiliary Front View
Auxiliary Vertical Plane VP
AVP a’
a1’ a’ A VP
a’o = a1’o1
a1’ y x1 x1 a y1 x y o o1
AVP a o1 o HP a x a
Procedure for drawing auxiliary view
Draw x1y1 at an angle a to xy
Draw aa1’ perpendicular to x1y1 such that a1’o1 = a’o HP y1

5. AUXILIARY INCLINED PLANE (AIP)- perpendicular to VP and inclined to HP
Auxiliary Top View
a1o1 = ao VP o1 a’ y1 y1
AIP a’ A o1
a1’ VP b x1 x y o
AIP b
a1’ x1 o a
90O a HP HP
Procedure for projecting A on AIP:
Draw front and top view a’ and a respectively
Draw x1y1 such that it makes an angle b with xy
Project a1’ on AIP by drawing a line a’a1’ such that a’a1’ is perpendicular to x1y1 and a1’o1 = ao
Auxiliary Top View

6. PROJECTIONS OF PT. A
Lines with same color have the same length
When 2 planes are perpendicular to the same third plane the distances of the projection of a point from the reference line (junction line) of 1st. 2 planes is the same
TOP TV a o a’
AIP
FRONT a1 A
AUXILIARY o1 o a1 a’ o1 FV
A line drawn parallel to the edges will join the two projected points a’ and a1 a
Distances Aa (point to front view)= a’o (in top view which is perpendicular to front view)= a1’o1 (in auxiliary view, which is also perpendicular to front view)

7. x2 X a1’ b1’ T a c1’ c 60o b y2 O Z y1 a’ 45o c’ c1 b’ F a1 Y b1 x1
Draw the auxiliary view of a plane ABC on a plane which is perpendicular to the frontal plane and inclined at an angle of 45o to the top plane. Draw another auxiliary view on a plane which is perpendicular to the top plane and inclined at an angle 60o to the frontal plane. Given A(50,10,30), B(10,40,0), C(10,30,50) USE III rd ANGLE
Distance of a1 from x1y1 = distance of a from OZ
Distance of b1 from x1y1 = distance of b from OZ
Distance of c1 from x1y1 = distance of c from OZ
Distance of a1’ from x2y2 = distance of a’ from OZ
Distance of b1’ from x2y2 = distance of b’ from OZ
Distance of c1’ from x2y2 = distance of c’ from OZ x2 X
a1’
b1’ T a 50 40 30
c1’ 20 c 10
60o b y2 O Z y1 10 20 a’ 50
45o 10 20 30 c’ c1 40 b’ 50 F a1 Y b1 x1

8. Projection of a cuboid on 2 auxiliary planes
Fold line h1
The figure shows the front view and top view of a cuboid
From these views, the auxiliary views are drawn on 2 planes:
i) Perpendicular to the top plane and at an angle a to the frontal plane,
ii) perpendicular to the frontal plane and at an angle b to the top plane
X2y2 is the junction line of plane perpendicular to the horizontal plane and the horizontal plane, hence drawn in the top view
X1y1 is the junction line of the plane perpendicular to the front view and the front view, hence drawn in the front view g1 TV e1 d1 f1 c1 a1
Viewing direction
e’, h’ b1
f’, g’
a’, d’
b’, c’ a y1 x y x1 b FV
Viewing direction
a, e
b, f b2 a2 f2
d, h
c, g c2 e2 d2 g2 h2

9. SECONDARY AUXILIARY VIEW
Required when the plane of view is oblique or not perpendicular to any of the principal planes.
First draw front and top views.
A primary auxiliary view is drawn first (which is perpendicular to one of the principal planes) with the view in a suitable direction.
A secondary auxiliary view is drawn on a plane that is perpendicular to the primary auxiliary view at an angle such that the appropriate view of the required feature is obtained.

10. Primary auxiliary view (PAV)b2 d2 a2
c2o2 1 2
Primary auxiliary view (PAV) c1 a1
b1d1 o1 T 1
Secondary auxiliary view (SAV) a o b
Given Top and Front views of a square pyramid. Obtain a view of the pyramid with edge oc viewed as a point. d c T F
-Axis for PAV is parallel to oc in the Top view.
-Axis for SAV is perpendicular to c1o1.
-o1c1 is the True Length. c2o2 overlap in the secondary auxiliary view o’
d’a’
c’b’

11. NOTE
All outermost lines or curves of a view are visible (solid).
Lines and curves joining the point closest to the axis in the previous view will be visible (solid)
Rest of the lines and curves may or may not be hidden (drawn dashed)

12. Secondary auxiliary view of a cube PA plane at 45o to Front and perpendicular to Top. SA plane is 60o to Top and perpendicular to PAP
Distances:
Primary auxiliary view
e1, f1, a1, b1 from x1y1 = e, f, a, b from xy
h1, g1, d1, c1 from x1y1 = h, g, d, c from xy
respectively
Secondary auxiliary view
e’, f’, a’, b’ from x1y1 = e2, f2, a2, b2 from x2y2
h’, g’, d’, c’ from x1y1 = h2, g2, d2, c2 from x2y2
f1, a1
g1, d1 e1 h1 b1 c1 x1
45o
e’,h’
f’, g’ TV
60o x2 y2
a’, d’
b’, c’ a2 f2 d2 g2 c2 e2 b2 h2
Direction of view is perpendicular to the fold line y y1 x
a, e
b, f FV
d, h
c, g