In this post I wanted to share with you a discovery I made recently while teaching an Inventor fundamentals class. I was actually demonstrating the new DWG Underlay functionality, and afterwards, illustrating the annotation tools within Inventor, including the Hole Note tool. What I received when trying to create a Hole Note was the following error message (see image below):
Now for some backdrop on how I got this error. The workflow you will see here is a valid scenario for bringing in AutoCAD DWG Underlays into Inventor, and then detailing the drawing. The drawing file was imported into inventor, but the drawing was a Model Space only file, with the geometry to be used, scaled at 2:1.
So, the geometry that I was projecting from AutoCAD to use to model my part was double the size. I used the Direct Edit command with the Scale option to scale the part down by .5 , resulting in a model that was true to scale. Finally, when detailing the drawing from this model, I tried to use the Hole and Thread note tool, but received the message as seen in the first image. For a threaded hole, it is understandable that there are too many interpretations to consider when using the command on a scaled hole, but in this case, it was projected from a DWG and extruded, so I would think that Inventor could figure this one out.
You can easily work around this issue by simply using the General Dimension command, and editing the dimension to reflect the type of Hole and Thread note desired. Or, you could simply wait to model the holes until after the part is scaled. In any case, using the AutoCAD DWG underlay tool is an awesome way to bring legacy or vendor data into your Inventor environment.