Plane on a flat lofted surface?

[AlexLemme]

I am currently trying to get a work plane onto a flat lofted surface.  I thought this would not be an issue but inventor is not letting me select. I have included a screenshot of the surface I am trying to use as well as the file. I'm sure it's something obvious I'm missing but I'm stumped. Appreciate any input!

[CCarreiras · Accepted solution]

Hi!

The issue is.... the face is not flat... is kind of warped surface...

You can have an approximation like a plane from 3 points.... depending what you need to do 

[blandb · Accepted solution]

Something must not be flat then. You can Check this by selecting (3) points around the face you want, and it will cut off a sliver of the part:

It appears that sketch! is not fully defined, it has (5) missing dimensions.

[mikejones · Accepted solution]

In sketch 1 you have two tapered edges lofting to two parallel edges in sketch 2 which is never going to give you a flat plane due to the twist in the profile.

Mike