Tipster Danny Korem reminds us to set our insert units in AutoCAD so that it can "automagically" scale files when they are xrefed.
"While working in a multidisciplinary environment — AEC, for instance — you can expect that you'll be getting multidisciplinary data from various design team members. This can reach your desktop in a wide variety of formats such as units, styles, and CAD standards; let's focus on units.
"As an architect and member of a design team, I get files from many engineers. Some of these files are unitless, some in meters, and some in millimeters, while we work in centimeters. We constantly cross-reference these files with ours to control the design progress. (Of course, we try hard to get rid of paperwork, and I have done exactly the same as long as xrefs have existed — long before 'going green' was a trend .)
"One of our procedures concerning incoming files is to check the units. You can open each file, type units, and check for it. Personally, I'm accustomed to typing InsUnits, and I recognize the numbers. If each file has its own units, it's OK to cross-reference them by attaching them as xrefs. Of course, the procedure is to always go to the WCS (World Coordinate System) and check the units. AutoCAD will compare the units of the current file with the units of the file being xrefed, then calculate the scale factors all by itself and reference the file. That makes things easier."
Notes from Cadalyst Tip Patrol: We use AutoCAD to make our jobs easier. The Insert Units setting is there to tell AutoCAD how to scale referenced files and inserted blocks so that they keep their true size. If you are working in feet and you reference a file that is drawn in meters, AutoCAD will scale the referenced file accordingly so that it stays at it true real-world size. If your file is inserted or referenced into a file with a different unit type, it will be scaled. This is a very handy and useful feature in AutoCAD. InsUnits is a number variable to set the Insert Units setting. You can type InsUnits and enter the numeric variable, or you can type Units and change the insert units that way.