Q: How do I convert my 2D drawings to 3D models?

A: Follow these steps:

1. Open the 2D drawing containing the reflector profile. The following steps assume that the 2D geometry is constructed in the XY plane of AutoCAD's World Coordinate System (WCS).
2. Define new layers in AutoCAD for 2D profiles and 3D surfaces for the various luminaire components, i.e. Profile-Main, Refl-Main, Profile-Lens, Tran-Lens, etc.
3. Delete extraneous geometry so that only the essential geometry remains that is required to make the 3D surfaces of the various luminaire parts, i.e. lines or polylines describing the reflector profile, lens profile and lamp holder locations.
4. Change the properties of the 2D entities so that they reside on the appropriate layers just created in AutoCAD, i.e. put the main reflector profile on layer Profile-Main.
5. Move the entities (lines, arcs, etc.) that comprise the 2D profiles of the luminaire components so that the center of the luminaire opening is located at (0,0,0) in AutoCAD's WCS.
6. Rotate the 2D profiles of the luminaire components so that the reflector opening is oriented toward the -Y axis if the luminaire produces downward directed light or toward the +Y axis if the luminaire produces upward directed light.
7. Change the view to an isometric view that allows the geometry to be seen in 3D. The "SE Isometric" view is a good choice. This can be obtained from the View toolbar or from the menu (R14: View - 3D Viewpoint - SE Isometric) or (2000-2002: View - 3D Views - SE Isometric)
8. From the main menu, select Modify - 3D Operation - Rotate 3D to rotate the 2D profiles for the luminaire geometry so that it is tilted up into the Front view (the Front view is in the world XZ plane). This is done by rotating the geometry +90° about the world X axis.
9. If the reflector is comprised of linear extrusions, then create the appropriate "direction vectors" in preparation for the "TABSURF" command. To make a direction vector, draw a "Line" entity the proper length and direction. Then make the appropriate 3D geometry layer current, for example Refl-Main, so that the new polyline mesh created by the TABSURF command will be created on the appropriate layer. After the mesh is created, it needs to be moved half its length so that it is centered about the profile used to create it. Note, all Line entities should be converted to Polylines using the "PEDIT" command. Also note that all Arc entities will be subdivided along their profile according to the SURFTAB1 setting.
10. If the reflector is comprised of circular components, then create the appropriate "axis of revolution" in preparation for the "REVSURF" command. To make an axis of revolution, draw a "Line" entity at the proper location and in the proper direction. Then make the appropriate 3D geometry layer current, for example Refl-Main, so that the new polyline mesh created by the REVSURF command will be created on the appropriate layer. The revolved surface will have an azimuthal resolution defined by the SURFTAB1 setting. Note, all Line entities should be converted to Polylines using the "PEDIT" command. Also note that all Arc entities will be subdivided along their profile according to the SURFTAB2 setting.
11. If SAILs are being used to orient surfaces, then make the appropriate SAILs for the 3D reflector surfaces using Lines with a linetype of "DASHED." Remember to put the SAILs onto the same layer as the reflector surfaces to which they are attached.
12. If the reflector is a linear extrusion, then construct the end plates using the 3DFACE command. Note that each 3DFACE is 4 sided.
13. Import the appropriate lamp model for the design. Rotate, move and scale the lamp as required so that it is placed correctly within the luminaire. Note that all lamp models import with a scale of inches. Thus, if the project is being drawn in millimeters, then the lamp model needs to be scaled by a factor of 25.4. When modifying a lamp model be sure to select all lamp entities at the ends and in the center of the model.
14. Copy the lamp model as needed to get the right number of lamps placed within the luminaire. Note that Photopia does not allow lamp models to be mirrored.
15. Turn on all lamp, reflector and lens layers for the 3D luminaire parts and turn off all construction and 2D profile layers. Then save the drawing so that it can be imported into Photopia.