Thanks again epicdoom. I have been studying several 3d cad programs, and have so far thought to start learning Fusion360, which should be free for hobbyists. But also I assume that being intended for professionals, it might be too difficult to learn. So sketchup might be a better choice for a hobbyist like me, who do not ever need all the fancy features that the more complex programs are offering. So you have turned my head, I have to start learning sketchup. Thank you!
About the 3d printers, those which I have so far seen, are producing much worse quality than I would like to have. If you want a complex part with perfectly smooth surface for your model to be printed, and after printing it still needs a lot of sanding and filling, much easier it would have been to produce the part with old school method, sawing, filing, sanding from stock. This is the fact that has so far prevented me buying a affordable 3d printer.