dimensioning autocad links

[conners_hey]

i have been dimensioning with suffixes in Revit on top of an imported link from AutoCAD. i am now trying to reload the link and a window comes up with a bunch of errors having to do with these dimensions and threatens to erase them if i proceed with the reload. does anyone know what this is all about and how to avoid losing all of the dimensions?

thanks!

[sleimgruber06]

Yes, because you have dimensioned to this AutoCAD link, those dimensions are basically associated with THAT linked view. When reloading you essentially putting in a NEW linked view. You will more than likely have to re-dimension to the reloaded link.

Hope this helps,

[conners_hey]

so everytime i reload the drawing i have to redimension it, even if it is only a few things that are different on the link (and not affecting the dimensions)?

[Firmso]

so everytime i reload the drawing i have to redimension it, even if it is only a few things that are different on the link (and not affecting the dimensions)?
One way to have those dimensions remain when removing links is by placing Ref Planes and dimensioning off of them instead of the linked object.
I hope this helps

[sleimgruber06]

One way to have those dimensions remain when removing links is by placing Ref Planes and dimensioning off of them instead of the linked object.
I hope this helps

I hadn't thought of that!
So basically I could go and draw these ref planes, and then set them onto a new workset so I could turn them on and off at will, instead of using "Hide Annotation in this View."

Thanks for the insight Firmso!

[mibzim]

We had the same problem... the dimensions do dissapear.

Firmso's solution isnt great though, because those reference planes dont move when the new link comes in, so you will end up with all the incorrect dimensions showing - more of a problem i think than having the dimensions deleted and forgetting to replace them.

[conners_hey]

so basically, the only thing to do to avoid this problem altogether would be to import the drawing and explode it before dimensioning it....is that correct?

thanks from a new and frustrated user...

[Rachel Ritchie]

About linking your Autocad files in to your Revit project.

Have you ever listed an Autocad object (like a line), and seen that “handle = ??…here’s an example, handle=2f.
LINE Layer: "0"
Space: Model space
Handle = 2f
from point, X= 9.0888 Y= 4.1476 Z= 0.0000
to point, X= 11.6208 Y= 4.1476 Z= 0.0000
Length = 2.5320, Angle in XY Plane = 0
Delta X = 2.5320, Delta Y = 0.0000, Delta Z = 0.0000

Well, it's my understanding, that handle is like an element ID. It has nothing to do with how it visually appears on the screen; it has to do with the file bytes and the placement of these bytes within the file itself or something like that. Anyway, if you delete the element (the line in this example), and redraw another in the exact same place, it will have a different handle.

When you dimension in Revit to things on a linked Autocad DWG, you are dimensioning to this “handle”. So, if the “handle” in the Autocad drawing changes, you will get the message "one or more dimension references are or have become invalid" next time you open your Revit file.

Your only option is to delete the dimension or cancel the load, which doesn’t do you much good either.

We tell our people:
Dont' constrain your model to a linked Autocad drawin file.
Don’t DIMENSION to a linked Autocad drawing.
Don’t ALIGN to and the lock the alignment of a linked Autocad drawing.

Of course, if you inserted (and did not link) the Autocad file, you won’t have any troubles (not these particular problems at least), but you also won’t receive any updated changes made to the Autocad file.

[conners_hey]

ok, thanks.

[mibzim]

so basically, the only thing to do to avoid this problem altogether would be to import the drawing and explode it before dimensioning it....is that correct?

thanks from a new and frustrated user...

Best not to explode your dwg's in your file as it slows it down tremendously