Page 77 - Engineering drawing from first principles using AutoCAD

70 Engineering drawinq [1"0111 first principles

Use the BREAI( feature to insert a space in the unwanted part of the ellipse. (Stage 2
shows one end completed and the other end before trimming.) It is then necessary to
clean up the two ends back to the tangency points. Use the TRIM facility in the Modify
menu. Choose this option and the Command line reads
Command: trim
Select cutting edge (s)
Select obj ects :

Click on the two lines which meets at the tangency point and form the profile, then press
<Enter>. The command line changes to

Select obj ects: 1 found
Select objects: 1 found.

lSOPLANE TOP

ISOPLANE RIGHT

Figure 3.2 ISOPLANE LEFT