DWG files are scalable image documents that store two- and three-dimensional blueprints and drafts. They're ideal for architects, engineers, and electricians, many of whom use DWG-dependent programs like AutoCAD to design circuits, homes and structures, according to a writer at File Info. For this reason, many people use a PNG-to-DWG conversion process to transfer their paper drafts into interactive design documents. PNG files are high-resolution bitmap images that are ideal for scanning detailed drawings on paper.
Decide if your file is detailed enough to require a manual conversion. According to Format Conversion, most PNG-to-DWG conversion programs produce more errors in the final document than manual converters, who go over the document repeatedly to make sure that each line in the image is represented as a scalable vector. If you're fine with a less precise conversion, skip to Step 3.
Contact a manual conversion service. According to AlmaCAD, most manual converters are trained to handle dense and detailed architectural drafts, engineering schematics and drawings of electrical circuits. Have the service perform the conversion, and you are done.
Download a PNG-to-DWG conversion program. Since many effective converters are posted online as free downloads, stay away from any conversion software that charges you a fee. Popular programs include Image 2 Cad and the free converter offered by Brothersoft. (See Resources for links.)
Scan the PNG to make sure that your original image file is an adequate scan of your paper document. Open the file on a viewer program—Apple Preview and Adobe Reader are popular options—and zoom in to various parts of the document. Make sure that each drawn structure is clear and easy to make out. If you aren't converting a scanned document, skip to Step 6. If you find that your PNG file is inadequate, rescan the paper document.
Convert the file. With most conversion programs, all this involves is choosing a PNG file and setting the destination folder for the new DWG file, then clicking "Convert".
Open the DWG file in a design program and determine if the conversion was adequate for your needs. Adobe Illustrator and the aforementioned AutoCad will work. Rotate the image, zoom in, and compare the displayed vectors to the lines on your original document. If the file is inadequate, return to Step 1 and repeat.