Graphic Communication

 Auxiliary views are additional views that are used in orthographic projection.  Auxiliary views are normally used to view the True Shape of a surface which does not face the Front Elevation, End Elevation or Plan at 90 o.  Auxiliary views can be drawn as Auxiliary Elevations or Auxiliary Plans.  An Auxiliary Elevation uses the same heights as the other Elevations and as with other Elevations it is projected from the Plan.  An Auxiliary Plan uses the same widths as the existing Plan and similarly to the Plan it is projected from the Elevation.  An Auxiliary view can be considered as looking at the object from different positions located somewhere between either the Elevation and End Elevation (for Auxiliary Elevations) or between the Plan and End Elevation (for Auxiliary Plans).

The block shown below shows a Front Elevation and an End Elevation with two Auxiliary Elevations between them. As can be seen the Auxiliary Elevation heights are the same as those on the Front and End Elevations. It appears that the viewer is moving slowly round the block and viewing it from different viewing positions at ground level.

 The block shown below shows a Plan and an End Elevation with two Auxiliary Plans between them.  As can be seen the Auxiliary Plan widths are the same as those on the Plan and End Elevation.  It appears that the viewer is moving slowly round the block and viewing it from different view points in a radius from directly above the block around to ground level.

 Unfortunately, because our object will be drawn on a piece of paper it will be difficult to ‘walk round the block’ to view it from different positions. We need to use some of the previously drawn views of the drawing to project our views.  What this means is that the views will be drawn in slightly different positions to that shown in the previous slide.  Each of the Auxiliary Elevations in the drawing will be projected from the Plan, in the same way that the Front Elevation has been drawn (and occasionally the End Elevation)  When drawing Auxiliary Elevations, the drawing will need to be drawn at the angle that you choose to view the block at.  For SQA purposes this will normally only be at 30 o, 45 o or 60 o (the usual angles of the class set squares) although there is no reason why other angles could not be used.

 The blocks shown here show the positions where Auxiliary Elevations might be positioned to show the Front View or different Elevations to the left hand side. plan Front Elevation End Elevation Auxiliary Elevation

 A similar situation occurs when drawing Auxiliary Plans.  Each of the Auxiliary Plans in the drawing will be projected from the Front Elevation, in the same way that the Plan was projected.  When drawing Auxiliary Plans, the drawing will again need to be drawn at the angle that you choose to view the block at.  For SQA purposes this will also normally only be at 30 o, 45 o or 60 o.

 The blocks shown here show the positions where Auxiliary Plans might be positioned.  Similar views could also be drawn to the right hand side of the Front Elevation. Plan Front Elevation End Elevation Auxiliary Plan

Department Of Technical Education