Sheet Metal - Part Wont Flatten

[aaron]

Its been a long while since I have run into something that I have drawn which I cannot get to flatten. I am using Inventor 2011. Any advice or help would be appreciated. If you can get it to work in 2012 or later, then I guess it is just time I upgrade. Thanks

[blair]

Looks like you have a compound curve with your part. Beyond that Inventor Sheet-Metal can unfold. I always use the rule if it can be done in a Brake, then it can be unfolded. This part looks like it would have to be stamped with the curved edge along the flat and each curved end is a different radius.

[JDMather]

How much leeway do you have on that design?

If you could do the curved portion as a conic.....

[aaron]

Blair,

That isn't a compount curve, it is a single 6" radius that is on a tapered cut. I could make that part on a roller and brake with ease. 

JD,

Unfortunately, I dont know the answer to that yet. It is a prototype piece for a new fan assembly I am working on, I haven't even gotten the chance to add the necessary flanges and the part will most likely be modified as I start on the subsequent parts. I did try lofting the part and it wouldn't work there either. If I removed the two flat planes it would flatten but as soon as I added one it wouldn't. I assume it is because the bend is going across different parts of the radius? What did you have in mind with the modification to the part? As alway, thanks for your help. 

[blair]

The intersection of the curved piece and the flat flange is curved. I believe this is where Inventor is having problems trying to flatten this item.

"never seen a brake do a curved line"

[aaron]

Blair,

Interesting. You are correct, although that was not my intention. It seems I need to try and redraw the part. I tried removing the lower plane and it still wouldnt flatten. The upper flange appears to be a straight line, I wouldve thought it would flatten, but no. I redrew it here as a loft (attached). I normally add the filets before I thicken, but that produced 0 progress, so I tried adding the filets after the thicken and the curved section flattens but the flanges do no, drawing it this way did produce straight lines at all bendst. Any luck at getting a similar part to flatten? I cant think if any other way to draw it. 

[blair]

There is a tutorial for the S-M creating a Cone. This might be one way and then add the flange after.