The best free alternative to DraftSight is LibreCAD, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 50 alternatives to DraftSight and many of them is free so hopefully you can find a suitable replacement. Other interesting free alternatives to DraftSight are QCAD (Free Personal), BRL-CAD (Free, Open Source), pCon.planner (Free) and Onshape (Free Personal).
CAD X11® Free include 3-D wireframe modeling, surfacing, DXF import, 2-D drafting with ANSI, ISO and JIS dimensioning, geometric tolerancing, TrueType Font support, undo/redo, dynamic rotations, multiple views, data verification, geometric analysis, crosshatching, Windows...
2-D engineering drawing editor that supports hierarchical object description. It is inspired by Hewlett-Packard's proprietary HP PIGLET (Personal Interactive Graphic Layout EdiTor), which later became the commercial Graffy editor by DURST CAD.
NttCAD: free, simple 2D/3D CAD software, multi-platform (works on Windows, Mac, linux...). Programmable in Java language. Small program size and fast download. Saves in autocad dxf, svg and NttCAD formats.
Design Review lets you view, mark up, print, and track changes to 2D and 3D files. Work with: DWF, DWFx, DWG, and DXF (requires DWG TrueView); Adobe PDF; as well as.bmp, .jpg, .gif, .pcx, .pct, .png, .rlc, .tga, .tif, .mil, .cal, and more.
As a simple, lightweight, and powerful tool for viewing and measuring CAD drawing, CAD Reader supports *.dwg/*.dxf files and is available to add annotations on the drawing and do some quick measurement.