Stuck again, Michael.

 From:  Michael Gibson
2069.4 In reply to 2069.3 
Hi Rudy - no problem!

Just a bit more information for you here -

When you mirror something to make a full shape from a half shape, it can cause this kind of problem when the half shape does not have an ending direction that is exactly perpendicular to the mirror axis.

Here is an example where it is a bit exaggerated to help illustrate.

Here is a half-shape curve that I drew with the Freeform / Control points curve tool:

This curve is not going to be suitable for mirroring into a single seamless shape because of the shape it has at the end.

The ending direction is defined by these 2 control points:

If you imagine a line between those points, that is the direction of the curve at the end, like this:

To get a smooth mirror, that direction must be perpendicular to the mirror line, not slanted at any kind of an angle. So those 2 points have to be lined up horizontally like this:

The Transform/Align command can be helpful for editing points to line up horizontally like this.

Anyway that same situation is what was happening with your curve, although it was not such a large amount as in the example above so it was harder to notice.

But even a small deviation by just a couple of degrees can end up causing gaps when other things try to build and hang off from those curves like the sweep does. So it really helps to get those points lined up more precisely before mirroring.

In the future I would like to make some more automatic tune-ups to these kinds of things so that it would solve the problem for you. But it is a somewhat delicate area to make automatic edits that could change the shapes of your objects, I want to make sure that I don't do something that modifies them too much.

- Michael