The input body is invalid

[Anonymous]

Hello,

I'm trying to create a flat pattern of a folded pipe but I get the error message "The input body is invalid".

I have used two 180 degree folds to create the pipe. I have also calculated the bend allowance to the very minimum.

Is this situation considered as a feature overlapping or what might be the main reason behind this? Any suggestions/solutions?

Thanks for your time!

[JDMather · Accepted solution]

You are doing too much work.

It is (almost) always better to model in finished form rather than using Fold.

Install Service Pack 2 and

use Contoured Flange.

or use Contour Roll.

[Anonymous]

Thank you for your quick reply.
I studied the techniques you presented and they are definitely the way to go. I picked up Contour Flange immediately.

I noticed that both of the presented parts had a small gap for welding. I made a small gap to my model too and Inventor was then able to create a flat pattern.
I'm still trying to learn and was wondering, is the program unable to create a flat pattern out of a part which has been folded 360 degrees? Are the opposite faces overlapping each other and therefore Inventor is unable to unfold the part?

I do realize that the gap is necessary but I'm asking to make sure and for later troubleshooting. Don't worry, I will be using Contour Flange from now on but I need to know.

[JDMather]

If you look on the Sheetmetal Ribbon you will see a tool for Rip. 

I modeled the gap into my part, but if I hadn't done that I would need to use the Rip tool to, well, rip the part so that it could be unfolded.