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.
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.
Charles (Chuck) Rheault CADD Manager
MDOT State Highway Administration
what would happen if you changed a dgn to survey feet first and then saved as dwg... then ref attach the DWG to the SF dgn
do all the objects line up can you also ref in on top the orginal FT are there any differences?
If your FT dgn doesnt match your DWG and more importantly the DGN (SF) model, but your DGN (SF) matches your DWG then I think its converted correctly...even though acad is unitless it still uses Cartesian coords from 0,0.
Lorys
Started msnt work 1990 - Retired Nov 2022 ( oh boy am I old )
But was long time user V8iss10 (8.11.09.919) dabbler CE update 16 (10.16.00.80)
MicroStation user since 1990 Melbourne Australia.click link to PM me