Solid Cylinder cut at an angle Drawing Abilities Teacher © J Lewis 2004

Orthographic projection Plan Elevation Draw the Plan and Elevation of the cylinder, which is cut at an angle of 30 ° © J Lewis 2004

Drawing generators Divide the plan into 12 equal generators at 30 °, number these as shown © J Lewis 2004 Plan Elevation

Inserting reference points Project the vertical generators down to the Elevation and number as shown © J Lewis 2004 Elevation

Starting the End Elevation Construct the outline of the End Elevation, point 3 at the front and the generators shown © J Lewis 2004 ElevationEnd Elevation

Drawing horizontal generators Construct horizontals where the vertical generators cross the sloping top of the Elevation © J Lewis 2004 ElevationEnd Elevation

Marking out the shape Now mark the End Elevation. Points are found where horizontal lines cross similar marked generators. © J Lewis 2004 ElevationEnd Elevation

Drawing the ellipse Draw an ellipse passing through the marked points © J Lewis 2004 ElevationEnd Elevation

Finished End Elevation © J Lewis 2004

Surface Development Project horizontals from the Elevation and step off to circumference length in 12 steps © J Lewis 2004 Elevation

Marking points Mark the reference points carefully as shown below © J Lewis 2004 Elevation

Joining the points Join the points with a smooth curve © J Lewis 2004 Elevation

Finished Surface Development © J Lewis 2004 Plan Elevation Surface Development

Dealing with Cones Cones are dealt with in a similar way to cylinders The Plan and Elevation of the cone, which is cut at an angle of 30 ° by the plane A – A are shown below © J Lewis 2004

Drawing generators Divide the Plan into 12 equal generators at 30 °, number these as shown © J Lewis 2004

Inserting reference points Project the vertical generators down to the Elevation and number as shown © J Lewis 2004

Drawing Surface Generators Draw surface generators as shown © J Lewis 2004

Starting the End Elevation Construct the outline of the End Elevation, point 3 at the front and the generators shown © J Lewis 2004 ElevationEnd Elevation

Starting the End Elevation Construct surface generators on the End Elevation as shown © J Lewis 2004 ElevationEnd Elevation

Drawing the End Elevation Construct horizontals as shown © J Lewis 2004 ElevationEnd Elevation

Drawing the End Elevation Draw a smooth curve as shown on the End Elevation © J Lewis 2004 End Elevation

Starting the Plan Construct the lines shown from the Elevation up to the Plan © J Lewis 2004 Elevation Plan

Completing the Plan Transfer the measurement on 6 – 12 on the End Elevation to the same generator on the Plan and draw a smooth curve as shown. © J Lewis 2004 Elevation Plan End Elevation

Finished Orthographic Projection © J Lewis 2004

Surface Development Step off to circumference length in 12 steps along an arc with the same radius as generator 3 as shown – this is a true length of side Mark off the true lengths of each of the generators as shown and draw the surface development © J Lewis 2004 Elevation