"So I want to do some 3D CAD modelling..." Topic

Yes, indeed, I do. After looking at the wickedly-cool stuff coming out from such august personages as John Bear Ross and the artists at Shapeways, I really want to play around with some 3D designing and see what I can come up with.

I have Sketchup and an older copy of Rhino3D, but neither seems very intuitive (I couldn't even figure out how to delete a portion of something I'd drawn, like "drilling" a hole in a block!) and I can't seem to find much in the way of beginners' resources. So I'm wondering what all everyone else is using and what resources you might recommend for someone wanting to jump into the game. Are there forums somewhere that are good for that sort of thing?

Thanks!
jav98

Check out Zbrush – it's a great digital sculpting program that can export as OBJ or STL files (which can be 3D printed)

In Rhino3D I create a surface in the shape I want to cut out, then extrude the surface as a solid through my model, then do a boolean difference to subtract that extrusion from the model. There are many other ways to do it, this was the first I thought of, after several years away from Rhino work.

For example,

1)create a box shape
2) go to one of your x/y/z views and make a surface that lies parallel to your box – I usually use Surface/Plane/corner to corner (I did mine in Front view, and checked in Right view that it was outside my box shape)
3) draw the shape you want to cut out (I made a circle with centerpoint and radius in front view, and checked that it is farther from the plane – in Right view I see [side of circle] – Plane – Box)
4) project the circle onto the plane (Project to surface command)
5) trim off the plane portions lying outside the circle (Trim command)
6) From the Menu bar at the top, extrude a solid shape from your circle through the box shape (Solid/Extrude Surface>Straight command, drag it in the right view so it goes all the way through the box shape)

at this point make sure this is where you want the hole to be…

7) Use the boolean difference command to remove your extruded shape from your box shape (Solid tools/Boolean difference). make sure you specify the right order -- pick your target box first, then the extrusion you want to remove.

The end result is a boxy solid with a circular hole drilled through it.

Takes MUCH longer to write up than to do.

I used to use Wings 3D (open source) when I was doing some terrain stuff that I sent off to 3d-art-to-part for rapid prototyping. There was a bit of a learning curve but it was not too bad (and in fact may have been made steeper by my previous 2D CAD experience, since some things did not work as I expected them to). I use Sketch Up for some things now, but Wings seemed to me to be much more amenable to precision drawing. Sketch Up, to me, is for exactly that – sketching.

Doug

Any program will need some practice before it can feel intuitive. So, learn the basics first. Not just how to use the program but how to model something in 3D.

On Sketchup and Rhino 3D.

Doing what Cpt Arexu describes in Sketchup would be:
- Draw rectangle.
- Pull rectangle to create box.
- Draw circle on reactangle.
- Push resulting disc through the box to make a hole. Don't forget to stop at the other wall.

Sketchup is actually very easy to use as it was made with people in mind with no experience in 3D modelling. You can make very complex models with it if you want (check the gallery). Loads of tutorials on the Google site by the way.

Rhino 3D is a tad more complex since it's a CAD program. So it's more geared to people trained in Engineering. I think there are tutorials with the installation files but am not sure.

What do I use?
Professionally (I'm a mechanical engineer working as a PDM software consultant) I'm mostly working with SoidWorks.A very powerful 3D CAD package well suited for mechanical design. But too expensive for home use.

Recommendations. Depends on what you want to make.

For solids based 3D mechanical CAD software:
Crea Elements, non history solids based CAD package. Free license limitation is 60 parts per assembly. Enough for miniatures design. link

Organic design (more like sculpting with clay – freeform).
Sculptris: link

Wings3D could be a good program to try too.

If you want to go for 3D printing, make sure you can get the output into stl files. Crea can do this directly, Sculptris will need a translator. You can use meschlab for that: meshlab.sourceforge.net

Try both and use them to learn 3D modelling.

There are many more programs around though. But I prefer these.

Forgot a few bits.

About making models in 3D. The different 3D models have different approaches.

3D solids. Most used in CAD applications like SolidWorks, Crea, Inventor, SolidEdge, etc. Here you define "solid" shapes (things have a thickness) and start to manipulate (drill holes, add bits, etc.) then for the details. It feels a bit like working with them in a machineshop.

3D surface: Blender, Wings3D (from the description – not used it myself), etc. Here the emphasis is more on defining a surface. If you remove a surface you are looking at a hollow with 0 thickness walls. Less formula and parameter driven than working with Solids. Nice for freeform.

3D sculpting (not sure of the official name). As if you are kneading a bit of putty. Z-brush, Scultpris, CB Model Pro, etc.

Many programs combine functions of the three though. SolidWorks can for instance do all three but is still best at solid modelling.

Also, if you want to do 3D printing you have to keep in mind that you need to deliver a correct stl file. Some programs can generate them themselves but others will need a translator. Meschlab is a nice one: meshlab.sourceforge.net

Note, stl models which ar used for 3D printing are als

o directly accessible through that program if you need to check them or modify them directly.

Rhino3D is another surface modeler that works like Minimaker says. I should do more with solidworks but i use it so little i forget all the capabilities.

I used ViaCad from Punch Software. Not overly expensive and has some good tutorials.