Understanding Annotative Scales and XREFs

[m_kingdon]

Hi all,

I made a bit of a fool of myself the other day when a colleague asked me why annotative text from an XREF was not adjusting to a new viewport scale.  I incorrectly declared that XREFs don't carry over the annotative link, only to discover they did!

However, in order to change the scale of an annotative object, the current drawing/viewport scale has to be changed to an XREF scale.

For example.  I have a proposed drawing at 1:500, I want to change the scale to 1:250.  In order for annotative objects in the XREF to response, I have to choose the scale of 1:250_XREF in the current drawing.

Is this correct?  Why are the 1:250 and 1:250_XREF scales both necessary?  It seems that I need to scale my drawing based on the scales available in my XREF, rather than vice verse.  To me this seems counter-intuitive?

[RobDraw · Accepted solution]

I've never utilized annotation scaling from an XREF but I think I can shed a little light on this.

Annotative scales as you see them are a name assigned to a scaling factor. You can have different names for the same factor. Everything in an XREF has it's name prefixed with XREF to prevent any conflicts. In order for the annotative scaling from the XREF to work, you need to refer to the XREF scale.

HTH.

[m_kingdon]

Thanks Rob, I have a better understanding now.

I have XREFed the offending base drawing into a test drawing and found the scales and annotative objects updated fine.

I think the problem is people in the office scale drawings using different maths.  Either with a scale of 1/0.01 or 1000/100.  Both equal 1:100 but when scaling the drawing at 1000/100, the annotative objects do not response, even though the scale indicates 1:100.

I also think that the XREF drawing was locked and new scales could not be saved onto the drawing.

[RonaKiernan]

We try to avoid having those pesky "_XREF" annotation scales, which are created when your host drawing does not have an annotation scale with the same name as the one the reference drawing.  The simple solution is to add the same anno scale definition that you set in the reference drawing to the host drawing prior to attaching the reference file.  If the host drawing is a paper space "sheet" file, you will have to switch to Model Space to add the anno scale.  Also, the names have to be exactly the same or AutoCAD will create an "_XREF" version  in the host drawing.  Hope this helps ...