To Modify Snap Line Attachment or Spacing
1. Select a snap line and right-click the line to display the shortcut menu.
2. Click Edit Attachment. The MOD SNAP ATT menu appears in the Menu Manager. Click one of these commands:
Keep Position—Maintain the position of the snap line.
Change Orient—Reroute the snap line, changing its orientation by assigning the offset of the existing reference to the new reference.
Offset View—Reroute the snap line attachment to a view border.
Offset Object—Reroute the snap line attachment to other geometry or another snap line.
3. Specify a new reference. The snap line attachment changes.
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You can manipulate snap lines in several other ways:
To remove a snap line, select the line and click Annotate > Delete.  Once you delete a snap line, any items located on it are free.
To change the position of a snap line, select the line and drag it to its new position. The system updates all items located on the moved snap line after you choose a new location.
To control the length (position of the endpoints) of a snap line, select the line and drag an endpoint (handle).
To change the spacing of a snap line, select the line, right-click on the line, and then choose Properties on the shortcut menu. Enter a new spacing value and press ENTER. Creo Parametric updates all items located on the moved snap line after you choose a new location.