Hi ftgil2, just a few general tips and some additional explanation -

Like JPBWEB mentions above, it can be helpful to use as small a number of sections as possible.

That's because each section you add kind of adds some more "pressure" in a certain sense to force the surface to run exactly through it. Additional pressure like that will tend to cause undulations to happen.

You can see an example of undulations just in curve drawing as well, for example if you have 4 points like this and put a curve through them:





You can see the kind of bulging that happens there - that's similar to the undulations that can happen in surface construction as well. It is technically possible to avoid bulging with many sections if each section is very exactly positioned at a kind of incremental smooth step from each other, but in practice this becomes difficult to do with drawn curves because it's hard to visualize exactly how each sub-section of each curve is connected to each other.

One way to avoid bulging with curve drawing is instead of forcing the curve through those points, just make it guided by those points by using Draw curve > Freeform > Control points, which makes a result like this:




The equivalent for lofting is to use the "Loft Style: Loose" option for the Loft command, which does a similar kind of thing for surfaces, the surface is generally guided by the curves but not forced to go exactly through them other than the first and last one. It reduces undulations at a cost of control over exactly where the surface goes through.


So then the other tip that JPBWEB gives above about building a bulbous section as a separate piece is also very good advice. It kind of fits in with what I was trying to describe above with undulations - if you try to model a sudden change in the shape of a surface all within one single loft or network command, it will then be a source of undulations. So try to only make a single loft or single network that has a kind of smooth continuing form to it.

If things change shape in one area, try to create that as an independent separate surface instead of trying to do it all in one go. Then you can use some other tools like Fillets or Blend to make a connection between those pieces.

- Michael