LibreCAD - an open source AutoCAD clone that's still in development and is also available in Linux. I tested it a few months ago and didn't like it very much. Couldn't find some functionalities that have been commonplace in AutoCAD forever (like snap settings) and the icons seemed very unfamiliar, but none of this will be a problem to you if you're new to CAD. - Source: Reddit / 27 days ago
Oooh this sounds frustrating. Have you heard of LibreCAD? And there's other free options if that doesn't work for you. There's also Blendr but that's very time consuming to learn. - Source: Reddit / 7 days ago
I'm not completely sure what the "standard" tunnel would look like but here is a rough idea cross-section (quickly sketched up in LibreCAD):. - Source: Reddit / 4 days ago
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
FreeCAD - An open-source parametric 3D modeler
DraftSight - Discover Dassault Systèmes®' DRAFTSIGHT™ Professional CAD software that lets you create, edit, view and markup any kind of 2D drawing. Learn more here.
SolidWorks - Dassault Systèmes SolidWorks Corp. develops and markets 3D CAD design software, analysis software, and product data management software. SolidWorks is the leading supplier of 3D CAD product design engineering software.
Autodesk AutoCAD - Autodesk AutoCAD is a commercial computer-aided design (CAD) and drafting software application.
nanoCAD - nanoCAD is a pro-grade 2D CAD system with native DWG support and full customizability.