First, please note that drawings are almost always drawn in real size (1:1) with a CAD system. If this is not the case, please correct your drawing first.
If your drawing has a drawing border or header, scale the border or header instead of scaling your drawing. For example, if your drawing is to be printed with a scale of 1:5 (factor 0.2 or five times smaller than real size), scale your drawing border or drawing header with a factor of 5, i.e. insert it five times larger than you want it to print.
1. Open the DXF/DWG file with QCAD.
2. Edit > Drawing Preferences
3. Check and adjust 'Printing > Page > Paper Size' and 'Scale' (if known):
3. File > Print Preview
4. If the desired scale of the drawing is NOT known, click the button to adjust the drawing scale to the chosen paper:
5. Optionally, adjust the scale to the accurate, desired scale (10:1 in this example):
6. Optionally, adjust the paper position using the tool 'Move Paper Position':
7. To print in black / white or gray scale, click the appropriate icon in the options tool bar:
8. Your drawing should be shown on a white paper as shown here. If your drawing is shown on a gray background, please check your paper and scale settings.
9. To print the drawing, choose 'File > Print'.
10. To export the drawing to PDF, choose 'File > PDF Export'.