From an old post is now clear to me that there is no automatic way to add thickness to a complex surface like the one attached so I will have to do it manually. However, I am not sure of the right work flow to achieve this. Any suggestions?

Thanks
Ricardo

Hi Ricardo, yeah something like that is not going to get thickened automatically, in particular areas that are very tightly curved in a small area like this spot you have here are problematic:



What thickness are you trying to make?

The most basic starting point is to use Edit > Separate on the object so that you have all individual surfaces and then run Construct > Offset to generate offset surfaces of those. That will then give you a bunch of surfaces to work with, many of which will need to be extended areas built or trimmed with other surrounding surfaces.

For areas where the surfaces are all smooth to one another and don't have super sharp hooks like the above, you can leave those areas joined together and offset them as a connected object.

Another area that will cause difficulty is the degnerate corner situation that this surface has - it's not good to build a 4-sided surface with 2 of the sides tangent to one another, it makes for an indistinct corner which can easily be folding back over itself a slight amount making for a chaotic surface normal in that area of the surface:




Probably the actual easiest way to build a thick result from this would be to import the model into a different CAD program that has a better thickening mechanism in it, but that particular surface above will probably complicate the transfer into a different program too. That's the same surface that has the sharp hook on it also so you may need to actually reconstruct that particular surface to be better quality as a first step.

- Michael

Another thing that can help in general with thickening is to form your object into a solid and then shell it rather than trying to thicken a surface. That's because when thickening a surface it's easy for the "side wall" direction to not be very well defined, while with a solid the shelling the side walls get to come from existing geometry.

But you've got enough problematic things in this shape that just that alone isn't going to get the job done I'm sure.

- Michael

Here's your file converted to a solid by creating 2 planar surfaces to seal off the open areas and joining those all together.

This then can be exported into ViaCAD using SAT format, but ViaCAD will not shell it as-is I think because of the poorly formed surface corner that I show in the second set of screenshots above.

So you'll probably need to delete that particular surface and construct something better in that area and then try to go into ViaCAD after that.

Usually it's not very good to directly surface 4 curves where they do not form a distinct corner area (where 2 sides of the surface are smooth to one another). It makes for an degenerate surface normal in that spot and that messes up offsetting operations. So instead of trying to build a surface that has a corner like that you may need to build an extended surface that is better formed and then intersect it with the surrounding areas instead.

- Michael

Also this surface as well may be probematic due to it's corner shape too:



The surface is highly compressed in that small area and if the 2 surface edges are exactly anti-tangent there (maybe they're not quite, not quite sure), that's also a type of degenerate corner situation as well which again is bad for offset operations.

The way surface normals of a surface are defined is by a direction that is a shared perpendicular between the U and V parametric directions at that point. When the directions form a straight line with one another, either by pointing in the same direction or exactly opposite directions this calculation becomes indistinct.

So because of that areas that are shaped like that usually can't be a direct part of the base underlying surface and instead need to be trim curves that are on a broader more regularly formed surface instead.

Anyway, these 2 particular surfaces are going to be the most problematic things here.

- Michael