converting DGN (ft) to DWG (sf)

Question

I am needing to convert an existing dgn file in FT unit to a DWG with a unit of SF (Survey Foot). I have already modified the units.def file so when I attach a file I can choose the proper unit, but I don't have the same option when saving as dwg.

Reginald Wallace · Answer

Chris, Are you trying to have the working units in the DWG file read as survey feet in MicroStation or AutoCAD? I ask this because DWG format does not really have a linear unit concept and it really is a unitless system. There is no reliable way to determine what units are used in a DWG file. You can open a DWG file in MicroStation and set the working units in the DWG options or going to the Design File Settings>Working Units. This does not apply in AutoCAD as the environment is a unitless system. See the following blog that discusses DWG units. communities.bentley.com/.../dwg-units 
 AutoCAD does not have survey feet, but there should not be actual difference in coordinates or sizes. The only difference is readout.