- if they are drawing in just autocad, you will be relegated (restricted) to planar equal area coordinate systems as the output.
- if they are drawing using autocad map3d then there is at least a chance that the drawing is in an actual crs to start with.
if 1 then you wil need to move, rotate, scale the dwg using a known point as "base point".
I ussually do them in the order listed unless the scale is WAY out. you should hope not because that means you are changeing from something other than a similar measure unit. you need a line connecting two known points in the data.
find a point that you know the coordinates for and also has a position in the dwg.
Use that as base point.
Turn on /thaw and unlock all layers.
move all (command) m(enter) all(enter)
select known point as base.
type in the coordinate of the known point.
If you don't need to scale first to be able to detect the angle you need to rotate. go to the rotate command.
select the SAME base point. (read the command line carefully).
p(for previous selection)
select the same base point
select a point in the data that you have the second set of coordinates for.
now type the second set of coordinates.
(doesn't matter if they are scaled correctly you have both data in the correct angle now.)
On to the third step. scaling.
You are using empirical scaling. you take the distance of something and give it the correct distance.
So type the command scale(enter)
type p(for previous) (enter)
select the SAME base point
r(for reference) (enter)
select the base point again
now select the second known point
now type @x,y (where x is the horizontal coordinate and y is the vertical) (with an @ symbol in front is absolute location)
If all went well you should be done...
Oh i'm sure you just did that on a copy of original
If 2 just set the coordinate system in map and export to shp.
If I mistype or missed a step I aplogize. that was all from memory
let me know if there are problems