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# Use spherical coordinates in 3D AutoCAD drawings

Spherical coordinates are a way of specifying coordinates in 3D. Mostly, you use them with the LINE command. They’re good for finding a coordinate that you might use in a solid or surface. (I cover cylindrical coordinates, which are similar, here.)

Spherical coordinates have the format distance<angle<angle. An example would be 6<40<20. The 3 parts of the coordinate are as follows:

1. Distance: Units in the XY plane from the last point
2. Angle: Degrees from the X axis in the XY plane
3. Second angle: Degrees from the XY plane along the Z axis

Spherical coordinates can be absolute or relative. You don’t need the @ symbol to make relative coordinates if Dynamic Input is on and set to the default option of relative coordinates.

Here you see a red line drawn from 8,5 to 6<40<20. Note that the length of the line is the same as the distance in the coordinate (unlike cylindrical coordinates).

Do you use spherical units? When do you find them useful?

• Rolland Grigsby