CHAPTER 9Auxiliary Views

Learning ObjectivesDescribe the purpose of an auxiliary viewExplain how an auxiliary view is projectedDiscuss and draw viewing-plane lines related to auxiliary viewsDraw primary and secondary auxiliary views along with the related multiviews from given engineering problems

Auxiliary ViewsUse to find the:True length of a sloping lineTrue size and shape of an inclined surfaceForeshortened in principal viewsPoint view of an inclined line

Auxiliary ViewsDisplay the object in a plane other than one of the principal planesView the object differentlyEstablish other auxiliary viewsAllow you to dimension true size and shape

Auxiliary ViewsProjected 90from the inclined surface in the view where the inclined surface appears as a line or edgeUse orthographic projection and descriptive geometry

Partial Auxiliary View

Full Auxiliary View

Auxiliary View StandardsASMEASME Y14.3, Multi and Sectional View DrawingsISOAlternate view definition systems

The Glass Box Visualization Method

Projection LineIndicates alignment and view relationshipFrom a cornerCenterline (shown)Can be omitted

Drawing Curves in Auxiliary Views

View EnlargementsShow small detail more clearlyRemoved and linked using viewing-plane line or arrow method

Removed Auxiliary ViewsOut of normal arrangement with inclined surfaceAvoid when possible, but may be necessary when:Enlarging viewsSpace is limitedCan appear on a different sheet from where the view is taken if necessary

Rotated Auxiliary ViewsAvoid when possible, but can reduce the amount of space taken by the auxiliary viewViewing-plane line methodRotation arrow method

Rotated Auxiliary Views

Secondary Auxiliary ViewsAdjacent to and projected from:A primary auxiliary viewAnother secondary auxiliary viewRequired when a feature is in an oblique positionPrimary auxiliary view can take the place of a principle view

Secondary Auxiliary Views

GlossaryAuxiliary viewsShow the true size and shape of a surface that is not parallel to any of the six principal views.Descriptive geometryA drafting method used to study 3-D geometry with 2-D drafting applications where planes of projections analyze and describe the true geometric characteristics.ForeshortenedShorter than true length.

GlossaryFull auxiliary viewShows the true size and shape of the inclined surface and all the other features of the object projected onto the auxiliary plane.ObliqueThe feature is inclined, slanted or sloped in the principal view.Orthographic projectionAny projection of the features of an object onto an imaginary plane called a plane of projection.

GlossaryPartial auxiliary viewShows only the true size and shape of the inclined surface.Primary auxiliary viewsViews that are adjacent to and aligned with a principal view.