Flat Pattern for Grooved Folds

thomas_hotchkin

Hi all,

We're looking at getting some aluminium composite panel (ACP) folded up which is 3mm thick. In order to fold it they cut a 6mm wide V groove into the panel, which can then be folded by hand with effectively a 0mm outside radius. This is simple enough to do by hand on basic parts, but as it gets more complicated I need a way to get from a 3D model to a 2D flat pattern, something like sheet metal features. My issue is the sheet metal function can only work with a minimum external radius of ~3mm due to the material thickness which reduces the overall material length. Does anyone know of a workaround for this situation?

Cheers!

S1mon

If all the grooves are on one side, you could just model the aluminum skin on the outside with sheet metal, and if you need to check clearances or mounting points, have a separate (non-sheet metal) part which represents the full thickness of the folded up panel. It would be great if Onshape could represent this type of bend natively. It would also work for complex constructions from foam core.

EvanReese

The k-factor specifies where in the part the centerline of the bend is. A k-factor of 0.5 places the line right in the middle of the thickness. In other words, the inside half of your sheet will get compressed, and be shorter, and the outside half will stretch and get longer. Since materials behave differently under compression and tension, it's not always exactly in the middle. In your case, you could possibly get away with values of 1 or 0 for k-factor, which will keep one face or the other unchanged with the bend

thomas_hotchkin

S1mon said:

If all the grooves are on one side, you could just model the aluminum skin on the outside with sheet metal, and if you need to check clearances or mounting points, have a separate (non-sheet metal) part which represents the full thickness of the folded up panel. It would be great if Onshape could represent this type of bend natively. It would also work for complex constructions from foam core.

Thanks for the suggestion, that's what I've done for now but you're right it only works for bending in one direction and gets very difficult to work with in more complex models. 

Evan_Reese said:

The k-factor specifies where in the part the centerline of the bend is. A k-factor of 0.5 places the line right in the middle of the thickness. In other words, the inside half of your sheet will get compressed, and be shorter, and the outside half will stretch and get longer. Since materials behave differently under compression and tension, it's not always exactly in the middle. In your case, you could possibly get away with values of 1 or 0 for k-factor, which will keep one face or the other unchanged with the bend

Unfortunately because it's a sharp bend on the outside changing K factor alone can't get there because the radius always reduces the material.