Wednesday, January 24, 2007

The origin of trouble

This issue was reported to me by a fellow Revit user.

The user had created some door families that had a user named reference plane with the "is reference" property set to either strong or weak (he had already used Revit's pre-named reference planes). He used this reference plane to define the origin of the family, as well having a dimensional constraint to the reference plane. When he attempted to switch the family in a project with a similiar family he received constraint error messages causing the family(s) to fail.

This an edited response from Autodesk support:

The only stable references in the family instance are those produced by reference planes designated as named references (that is top, bottom, right, left, etc...). In the families that you created the reference used for alignment (and assigned to define the origin) is a weak reference in both families (referring to families submitted to Autodesk), so it's unstable, and the dimensional parameter fails when the family is replaced (via the type selector in a project).

They (Revit factory) have edited both families and set "Is Reference" of the Reference plane to "Right". Now the reference can be aligned and the instance can switch families.

To sum it all up, use the built in "is reference" names to define reference planes that will also define the origin for the family.

Hope you all find this helpful.

1 comment:

lastAutumn said...

Ohh, it's so interesting how you plan your work with those drawings... It's like my habit of scheduling credit card payments by drawing graphs))