I need a better CAD program

Or to get really good at creating polygon coordinates in my head.

jrv2fan_5My new fan duct is an improvement over the old one, which was an improvement over a bare fan with a dab of packing tape. (I made something that directs the air where I want it in a nearly straight line, rather than just making a box with holes at the other end and relying on pressure to force some air out.)

But it’s still lousy because I can’t do a good job of specifying the internal duct lines. I can see them in my mind, I could even probably make them out of cardboard (not at this scale) but I can’t figure out how to specify them in Openscad. The basic shapes are fine — I just extrude some hollow rectangles in the direction I want them to go — but the details of how they intersect are lousy, and I can’t fix it without piles and piles of math.

Maybe I could import the finished shape into Meshlab and tell it “cut out these faces and replace it with a face here“, but Meshlab always scares the blazes out of me. I can seldom predict what it will do, and half the time I end up with something  so nonmanifold you have to laugh.

I know Freecad has an openscad mode, but I’m not sure it will let me do the kind of multimodal design that I want (and I haven’t been able to climb the learning curve to find out). Should I just dive in? Any other suggestions?

This entry was posted in making, things that don't work and tagged , . Bookmark the permalink.

5 Responses to I need a better CAD program

  1. Speaking as an engineer who uses modeling software at work all the time and as a hobbyist who wants to own good software at a reasonable price, I have found Cubify Design to be far and away the best tool $200 can buy. http://cubify.com/products/design

    OpenScad is for mathemagicians, that you were able to make the image shown above is miraculous to me. If you want some other people’s opinions you can check out this thread I started on Thingiverse: “What is the best FREE 3D modeling software for serious use?”

    http://www.thingiverse.com/groups/engineering/topic:66

  2. paulwallich says:

    Thankee! This is going to take some investment of time (and maybe money).

  3. Have you tried Fusion 360?

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