surface modeling: best way to handle sharp transitions?

[maker9876]

In the below sketch there's a sharp transition between the spline curving gently down on the left hand side and the horizontal straight line to which it connects.

If the final ambition is to sweep this line and then turn it into a shell with thickness, what is the best way of getting a fairly sharp transition between the spline and the horizontal line, whilst maintaining the same general shape of the spline?

a) to add a tangent constraint, and then extra spline points?

b) to add a curvature constraint, and then extra spline points?

c) to model and thicken the shell without the horizontal portion and then add that (as a rectangular bar) using solid modelling?

d) something else?

It's a situation that keeps cropping up in different forms and curious to know how the pros would do this.

[TrippyLighting]

I don't think I understand what the problem is. 

[maker9876]

OK I'm a bit confused to.

As it turns out the above example, after being swept, thickens no problem in both inward and outward directions.

However it's often the case that thickening operations fail at transitions between splines and straight lines and that putting in a tangent or curvature constraint seems to sort out the problem. But then more spline points need to be added to adjust the shape back to the original idea. Haven't got to grips with this.

[TrippyLighting]

If you have an example we can track down what the problem is.

[laughingcreek · Accepted solution]

Sharp corners of themselves are usually handled fine with thicken.  A square thickens just fine for example.  There are, of course, many factors that effect thicken, but often when a curved element is involved it will be related to the quality of the curvature.  In the pic below, the curves on the left will thicken jut fine. but the curve on the right will only thicken a very small amount before failing.

they look pretty much the same till you check out the curvature combs in the next pic.