Question

When I attempt a loft I get the "self intersecting geometry" error. What
does it mean?
What am I doing wrong? and how do I solve it?

 

what it sounds like...the shape you have asked for folds or crosses over
itself somewhere.
check the order of your selections and the handle positions to make sure the
loft flows correctly from one section to the other.
also see that the direction of the start/end normals is correct and that the
end conditions you have imposed are able to be to be achieved in the
available space.
if your preview disappears as you construct then you know you have violated
practical conditions for a correct loft and you either have to fix your
error, back off your conditions, perhaps add guides or do things
differently.
HTH

 

It's a bit hard to tell from your description (more precise questions
result in more precise answers), but the message is probably pretty much
JUST AS IT SOUNDS. Let's say that the projected path of the loft, or
any guide path you're using, has a severe curve or twist in it . . .
pulling your profiles along the inside of the severe portion of the path
can result one or more profiles intersecting it/themselves as it/they
is/are swept along. SolidWorks says that's a boo-boo. It's the same
for sweeps as it is for lofts. Another possibility is that the vertices
you're using to transition from one profile to the next are not
analogous -- maybe you're not watching which points you are choosing.
Watch the preview with the highlighted path between the vertices
chosen. You need to select a vertex in each profile that is going to
give you the result you want. Extreme transitions (especially extreme
twists) can result in just such an error message.

One method of solving the type of problem you're encountering is to use
a guide curve, or even two guide curves, instead of merely relying on
the profiles to align the loft properly. As others have pointed out,
you REALLY need to do the tutorials that come with the software. I know
it may seem like time you just don't have at the moment, but how much
time are you losing when you encounter problems like the ones you've
been describing in your posts?

Mark 'Sporky' Stapleton
Watermark Design, LLC
www.h2omarkdesign.com