Face-based families moves after editing geometry of host

[mbednarzKYSGH]

Hi!
I have a problem with face-based families which moves after editing geometry of host. 
Below is example: When componenets is placed on face of host and then we will change shape of host - then family will be moved. Could we avoid this move. Are we able to place component in point - not referring to the edge? 

[RDAOU]

Is it a face based family or a Work Plane based. The behavior is slightly different between the two...Can you attach the family you are using?

Nonetheless, you should be able to constrain the elevation from level in any case

[mbednarzKYSGH]

Yes, it's Face based family:

I am attaching family which also is working as I described earlier.

So even if I could control its moves, I will not be able to control it only by editing host? I've got models with a lot hosted elements which are changed after editing hosts.

[RDAOU]

@mbednarzKYSGH 

See attached GIF...I simply placed a a generic model extrusion with a parametric sweep/void to round top or bottom and/or both top and bottom. Then I hosted the bracket family you posted on each of the 4 sides/faces of the GM. I cannot seem to replicate what is in the images you have posted.

• Rounding edges should not effect the extents of the Host. So most probably it is the void you are rounding the host with. 
• If the extents of the face/surface will be variable and your intent is to fix the brackets to certain positions on the hosting face, then you would need to
  1. Either lock/constrain the FB brackets to reference planes in the Host family or the project
  2. Or control the brackets using their Elevation from Level parameter

[mbednarzKYSGH]

Hi!
Here is a gif of how it looks in my case.
- The move is horizontal - so I can't control them by levels.
- This problem occurs when I want to add round corners to posts. In models, I've got too many families hosted to post so I cannot change them all. I am looking for a solution how to control it without editing families hosted to faces.

The change is editing profiles that define posts.

 

[RDAOU]

@mbednarzKYSGH 

Refer to previous reply bullet 2...that is normal behavior. The bracket is not constrained to anything on that face/workplane where you are hosting it. If you expect it to move with the form whenever  you change it, then you need to constrain the bracket to something

You need to note that FACE does not mean the shape itself. It is the surface or plane represented by the face of the object. Its extents of the plane/surface are not bound by the shape of the object.