SW2008 - Feature or No Feature

Extrude a thin flat part, i.e., something sheet metal thin.
Sketch on one of the thin edges.
Make the sketch cross both of the sketch surface edges.
Use select contour to pick the sections to extrude.
See if the contour tool doesn't use the underlying face edges as well
as the sketched edges.

Is this a Feature or not a Feature?

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Ah,.. you can do the same thing in SW2006.

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Actually I tried it in 2004 and it worked there too. I just ran across
it first in 2008. Most people probably don't run into it because they
sketch on a face that completely encloses the sketch. However, my
question still stands as to whether this is a legitimate feature. It
would seem that any feature that changes a sketches topology base on
the sketch plane boundaries would be a bad feature. In other words if
you sketch on a plane based on the narrow face instead of the face
itself the "feature" goes away.

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IIRC, this was added about the time of contour select or maybe one realease
later. I remember reading about it on one of the "what's new" pdfs. The
purpose is to enable rapid closing of a profile to the model edges without
having to use convert entities on the edges or "close sketch to model". The
nice part is that the contour automatically updates to most changes in the
face's edges.

Whether or not this is legitimate depends on what you mean by legitimate.
It does capture design intent, so long as your intent is to use the
sketched entities and whatever the rest of that face is. If you don't want
that, then sketch it explicitly, or explicitly select the remaining
regions.

 

I think I understand what you're saying...? It's a question of
weather or not the sketch feature has legitimate intent... cuz of the
boundary assumptions used with the contour selection and/or what is is
preserved/absorbed too maintain some intended boundary history after
the parent face deletion?

What's different in the latest release options is the option to delete
(now default) or preserve (old way) the child features....where in the
past the child sketch and feature would be preserved (default),.. is
this what your seeing?

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I think you get it. Suppose for example a hole was added to a face
prior to a sketch being used in a later feature. That hole would
change the contour selections and cause unexpected results.

I think the preserving of child features might be causing other
problems. I have found extrudes that can't seem to forget prior
selections.

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Yeah, it's understandable.... if people are going to use the easy
button options, they should expect assumptions and problems.
Personally, I do NOT use contour select.

I just laugh at the latest marketing crap which are selling auto
fillets to save everyone time!!!?!?!?!

People in north america wonder why engineering/production is going
overseas!?

Everyone wants a EASY BUTTON and also get paid the same $?!

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