1. The elevation and plan of an angled bearing block are shown.
Project an auxiliary elevation in the position indicated
PLAN
Auxiliary Elevations
AUXILIARY ELEVATION
ELEVATION

2. Auxiliary Elevations Drawing the Datum Lines
Start by projecting the extreme limits of the Auxiliary Elevation onto the given base line.
This should be done at the required angle – in this case 45o.
PLAN
Indicate the position of the two datum lines that will be used to calculate heights.
Auxiliary Elevations X’
AUXILIARY ELEVATION X X
ELEVATION X’

3. Auxiliary Elevations Finding Centres for Curves
PLAN
Measure the height of the base and the height to the centre line.
Transfer these dimensions to the Auxiliary Elevation.
Draw suitable lines to indicate these positions.
Auxiliary Elevations X’
AUXILIARY ELEVATION
ELEVATION X’

4. Auxiliary Elevations Construction of the Hole
PLAN
Looking at the drawing you should be fairly confident that the hole on the Auxiliary Elevation is circular and can be drawn using compass’s.
This fact can be checked by measuring the width and height of the hole from the Plan and Elevation and also confirming that there is a centre line to indicate that the shape is circular.
However, if you are not sure it is worthwhile constructing the shape.
Working with the front surface of the hole, project random cuts onto the Plan and then onto the Auxiliary Elevation. X
ELEVATION
Auxiliary Elevations X’
AUXILIARY ELEVATION X’

5. Auxiliary Elevations Construction of the Hole
PLAN
Measure the size from the datum line up to each of the points on the circle.
Transfer these dimensions onto the Auxiliary Elevation.
Draw a smooth curve through each of the points.
Auxiliary Elevations X’
AUXILIARY ELEVATION X
Front Elevation X’

6. Auxiliary Elevations Drawing the Top Curve
PLAN
The same process can be carried out for the round top of the angled bearing block.
If you are confident that the top is a half circle then the shape can be drawn with compass’s using the existing centre lines.
However, if you are not sure, measure the heights for the curve using the existing random lines and transfer the heights onto the Auxiliary Elevation.
Auxiliary Elevations X X’
AUXILIARY ELEVATION
ELEVATION X’

7. Auxiliary Elevations Outline the View
PLAN
Before starting to draw the base of the bearing block, the top can be finished by darkening the outlines.
Auxiliary Elevations X’
AUXILIARY ELEVATION
ELEVATION X’

8. Auxiliary Elevations Drawing the Base
PLAN
Drawing the Base
Project each of the corners of the base from the Plan to the Auxiliary Elevation.
Each of the edges can be darkened to finish the drawing.
Auxiliary Elevations X’
AUXILIARY ELEVATION X’

9. Auxiliary Elevations Finished Auxiliary Elevation PLAN