FS#2390 - Please add U.S. Survey Feet to the Unit / convert list
Yes I’m aware that the U.S. survey foot has to be discontinuing December, 31, 22. However - as we’ve learned in the past it takes decades until a unit will disappears for good. 
See also:
https://www.qcad.org/rsforum/viewtopic.php?f=8&t=9493&p=38245#p38245
Duplicate entry, see FS#2272
Regards,
CVH
Please refer to:
https://qcad.org/rsforum/viewtopic.php?f=30&t=9562
Regards,
CVH
Husky,
U.S. Survey units are added in the above fix in the ‘From’ box as requested.
It can’t be added in the ‘To’ box because dxf files can not be written in those units.
An attempt to write such documents (docUnits=21-24) with QCAD will revert to ‘inch’ without unit conversion.
How files are saved is outside the scope of the conversion tool.
In the replies to the fix, you then suggested including US units in the Drawing Preferences. Because it can’t be written in these units, the drawing should then become read-only. Handling any change to Drawing Preferences is also outside the scope of a unit conversion tool.
ACAD supports $INSUNITS=21 but the remark is quite clear on this:
‘The US Survey Feet setting is supported only for inserting or attaching drawings starting with AutoCAD 2017-based products.’
QCAD retrieves $INSUNITS values 0 through 24.
Drawings in U.S. Survey units rather come with $INSUNITS=0 (’None’).
Such files can be loaded, edited and saved back again.
Care should be taken because no automatic conversion will take place.
Drawings in U.S. Survey Feet ($INSUNITS=21) are reported in the QCAD Drawing Preferences as ‘None’, handled as ‘meters’ and saved as ‘inch’ like mentioned above.
For drawings with $INSUNITS 0-24 the conversion tool selects the appropriate unit in the ‘From’ box including U.S. Survey Units.
Regards,
CVH