It usually works best to create the reference planes first, and set the main
parameters to control them without any geometry created. Then create the
objects and align/lock or dimension/lock/parameter to the reference planes.
Stop once in awhile to edit the parameters under Family Types to ensure that
everything works right. That way you catch any errors before you've done
too many other things and have to backtrack too far.
-MJ
wrote in message news:5369235@discussion.autodesk.com...
In creating my family, I am having trouble setting up my parameters. After
placing and locking my reference planes to the two objects, I place the
dimension and add the parameter. But when I try to edit the distance within
that parameter, the constraint error message pops up. Is it possible to
create an editable parameter between two objects, e.g. to widen/narrow a
space?