Modifying the Scale of an Imported DWG/DXF

The information in this article applies to:

QUESTION

I have a DWG drawing that was drawn at a scale of 1" = 20', and when imported into Chief Architect it is the wrong size. How can I change the scale so it displays at the correct size? 

ANSWER

In Chief Architect, all architectural and CAD drawings in plan files are drawn at a one to one scale. A 24" X 24" cabinet really is 24" square, and a CAD line 8" long really is that length - regardless of how far you zoom in or out. To produce a scaled working drawing, the desired scale is specified when a view is sent to layout or printed.

Since drawings are not scaled in the Chief Architect drawing window, it is not possible to assign a scale to an imported drawing. If you have a DXF or DWG drawing that was not drawn at 1:1, it needs to be imported using a custom unit of measurement that takes the drawing's scale into account and converts it to a 1:1 drawing. 

To create a custom unit conversion

1. Open the Chief Architect plan in which you would like to import a DXF or DWG drawing and select Edit> Preferences from the menu if you're on a Windows PC or Chief Architect> Preferences if you're on a Mac.
   
   
   
2. On the Unit Conversions panel of the Preferences dialog, click the Add button.
   
   
   
   
   
3. In the Add Unit Conversion dialog that appears next:
   
   
   
   
   • Type a short, descriptive name for your custom unit in the Unit Name field.
     
     
   • Select a Measurement Type of length.
     
     
   • In the Multiply by field, type the scaling factor that the drawing is using. In this example, 20 is used.
     
     
   • In the to Convert to drop-down list, change the unit of measurement to the unit you want to convert to. In this example we are converting to feet so ft is selected from the drop-down.
     
     
   • Click OK to close the dialog and add your custom conversion to the Units list.
     
   
   

   There are several ways to do a unit conversion. For example, a scale of 1" = 20' can be re-scaled by multiplying by 20 and converting to feet. Or, it can be multiplied by 240 (12" X 20) and converted to inches.

   
   
4. Click OK to close the dialog and accept your changes.
   
   

To import a DXF or DWG file using a custom unit of measurement

1. Select CAD> CAD Detail Management from the menu and open a new CAD Detail window to import your drawing into.
   
   
   
2. Select File> Import> Import Drawing from the menu.
   
   
   
3. Follow the steps in the Import Drawing Assistant until you get to the Drawing Unit screen and select your new unit conversion from the drop-down.
   
   
   
   
   
4. Click the Next button and finish importing the drawing. You can use the dimension tools to verify that the drawing is not at the correct scale.