I learned mechanical drawing 20 years ago - but I would like to wear a CAD hat for a small project. 3D CAD, so I can print it on a 3D printer. Unfortunately, 3D CAD makes no sense to me.
Twenty years ago, they were just starting to teach CAD in college, but I didn't take those classes: I took drafting. I learned things the old way, pencil and scale rule and triangles and drafting tables and all that. I'm a little rusty, but I can still pull out the T-square and draw something up when I need to.
My problem: I have a small project -- a personal project, low budget, but the only way I think I'll get it to work is to fabricate it. Difficulty: gears, turny parts, etc. It would be an ideal project for 3D printing, because I've seen similar things. I haven't seen anything practical like I'd want, but people are making celphone cases with ornamental, working gears in them, so it can't be that hard, right?
For the life of me, I cannot grasp 3D CAD. I have downloaded SketchUp, tried 3DTin and 123D Design, got something called OpenSCAD, and it simply doesn't work. "I made a cube! Oh, look, now there's a cylinder next to it! Unfortunately I have no idea how big anything is or how to make any shape more complex than this!"
If I had a drafting table, I could put this to paper lickety-split. If I had a well-equipped shop, I could make it, too. I have neither capability at the moment, but this is what 3D CAD is for, right? Rapid
prototyping and one-offs, straight from the design to a physical copy?
I have seen the recent 3D CAD for the complete beginner
AskMe, but it's all focused on what software to use. It's not just you, though: other discussion areas and FAQs all recommend software, but don't tell how to use it.
What I need is conceptual
understanding. Tutorials, what the terminology means, how things actually happen. For example, I opened a SCAD file in a text editor and that made some sense -- some shapes are negative space? It was like a light turned on! How do I actually make something like that? I have no idea. Software doesn't just do
that, regardless of what program it is -- it expects me to tell it what I want done, and I don't possess that language.
So, Metafilter, please point me towards understanding
, rather than tools -- where does an old draftsman like me learn to use 3D CAD to get things done?