Converting AutoCAD Details to Revit Drafting Views - Part 2
Updated: Oct 10, 2020
In part 1, I discussed how to prepare AutoCAD files for conversion and set them up for success when bringing them into Revit.
Bringing the details into Revit
The first thing you should know about bring AutoCAD into Revit is that, although they are from the same company, AutoCAD will bloat a Revit Model. I am saying this because the file you are going to create these details, should not be the final location. It will be the location where all the junk will be left behind as we transfer the views into a new model that we will access on a regular basis.
The majority of your work will be done on the AutoCAD side prior to bringing the files into Revit, however the scaling of details especially when they are set up to be "Not To Scale" can lend itself to its own set of problems. The details that I was converting were no where near an accurate size, they were scaled down to fit nicely on drawings. Why this was an issue was that Revit does not like lines smaller than 1/32". So when we inserted these details into a drafting view at a scale 1:1, and explode the cad file, a dialog would pop up and tell me that lines were too small and then force me to delete the lines. I got around this by scaling up cad file x8 and then setting the scale of the view to 1:8 so that the view placed on sheet is identical in size.
Just inserting cad files into drafting views can be a tedious task on its own. I used Detail link from CTC software to help with some of this task by allowing it to import each file into a newly created drafting view and automatically scaling the file x8. I leave the colors for the CAD files to Preserve, this way i will be able to identify what hasn't been converted to the black lines that I have created.
This brought my roughly 400 cad files into drafting views inside of Revit. My next step is to get them scaled back down to the size I needed for my sheets. I also needed the view titles underneath them to be read "NOT TO SCALE". I was able to accomplish both with one task.
In the lower left hand corner of each view is the option to select scale and change it to Custom. The dialog box will show up where I can set my ratio to print correctly as well as what i am displaying for scale.
Now we have the views setup and the display showing correctly. For us, we had file name as the view name and Title on Sheet filled out with what we needed in the view title. Now we are ready to start working on exploding the CAD. I tend to select everything after the explode to see if any blocks in the AutoCAD file remained AutoCAD entities. Once you explode the CAD file within Revit, we get down to some of the more tedious tasks. Selecting all text in a view and switch them over to company standard text and replace any linework leaders and hatches. Switch over hatch patterns to those that are found in the Revit model (AutoCAD's sand hatch pattern does not show as well as Revit's due to small lines). All these were easy to identify because on the Revit side is black line and my CAD was colorful.
Other things that should happen inside Revit,
Delete all import line patterns
Periodically purge all text styles that are created from AutoCAD
Periodically purge any imported categories and DWG files in the purge dialog.
Make sure that no imported CAD files are left over in any views. I utilize Model Manager in RF Tools for this.
Once I was happy with what I cleaned up, I would create a new file from our template and use Insert Views from File command to transfer into this new file. It is here where I make sure that the views show up in the correct location in the project browser. If everything is done correctly, this file will be lighter than the original. We can disregard the original and are now ready to use the details.