Modelação tridimensional EXC 18

Exc 18:
download file at:

http://gaudi.fa.utl.pt/~20108209/18 exc.3dm

open model from past excercises:

Computing technical drawing data...... Press Esc to cancel
Command:  _ViewportProperties
Command:  l
Command:  line

20 surfaces added to selection.
Command:  M
Command:  _Move
Command:  l
Command:  line
Command:  M
Command:  _Move
Command:  l
Command:  line
Command:  _Polygon
Command:  l
Command:  line
Command:  Offset
22 curves added to selection.
Command:  co
Command:  copy

110 curves added to selection.
Command:  M
Command:  _Move

Command:  M
Command:  _Move

Command:  _Rotate

Command:  Rotate3D

 Command:  _BooleanDifference