1. Use the clear command: When the CAD file is too large, you can use the clear command to delete unnecessary layers, blocks and other objects to reduce the file size.

2. Use WBLOCK command: With the help of WBLOCK command, the graphics to be transmitted are partitioned to generate new graphics files, and the newly generated graphics files are used for transmission or archiving. Enter a command at the command line, press enter to open the window of saving blocks to hard disk, enter the file name and path (file storage location) of the target, select a datum point in CAD, then select an object, and press enter to generate a new graphic file in the specified folder.

3. Modify the drawing settings: in the process of CAD drawing, change the commonly used tff font to shx single line. Reduce the use of small line segments, an arc is also composed of n too short line segments, resulting in too large a picture.

4. Copy and paste into a new drawing: You can copy and paste the drawing to be reduced into a new drawing, and then reduce the drawing by adjusting the scale or cutting the drawing.

5.CAD file format conversion: CAD files can be converted into other formats, such as PDF and BMP, to reduce the file size. During the conversion, you can choose to compress the image quality or adjust the image resolution to further reduce the file size.

It should be noted that in the process of reducing CAD drawings, the accuracy and details of drawings may be lost to some extent. Therefore, before the operation, you need to carefully consider and back up the original file.