How to form a relief cuts in a curved flange in sheetmetal?
Hello.
I am designing a curved part that will later be manufactured from a sheet metal. The part has a flange around it and one side of it is curved. I can unfold or flatten the part but when I do there is no relief cuts in the flange area. If I try to hydroform the part from a cutout without doing a relief cuts the flange will wrinkle up, I was wondering if there is a trick to split these curved areas so when they are folded over they would form the flange much like in a 3-d design?
Attached is an image of the flange and image of the flat unfolded part.
I am working in Solidworks 2015
1 Answer
Hello Michael,
Without a model, my best guess is that you used a single swept flange for this. Because it is a continuous edge you sweep around, you will have no relief cuts.
Swept flange assumes you 'Form' the bend, as if you start out with the flat plate and push a mold into it, much like the production process of a pan.
If you want the relief cuts:
-interrupt the edge, and use separate swept flanges. Fill gaps perhaps with unfold/extrude/fold technique.
-use unfold, cut away what you think you need, then fold it up (tough to end up with the right shape that way)
-Activate the flat pattern, and manually add relief cuts yourself (no guarantee your end result will be watertight)
This is a good reason not to like the swept flange :)
Lofted bends is another sinful feature with the same vice.
If you happened to have SW Premium, you can also Insert > Surfaces > Flatten surface. That will show you a graph where the program needed to compress or stretch the model in order to flatten it. This might give you a good idea on where to place your relief cuts and how large those should be.
On the other hand, apparently you have already tried this model with a real plate. I would suggest to iron out the wrinkles as much as possible into as few folds as possible, than you can use the position and size of those folds for your relief cuts.
Good luck!
Elian
