I think I have understood You now, and would like to suggest following approach:
You understand the problem now. Horray!.
Sutch a simple problem that is not easy to solve.
Automatic export of flat pattern lines
Check gap between finished part and other parts
but what is to difficult with such a small slot?
Modeling with 3D CAD means to maintain to rules and possibilities.
You in fact can not bend this sheet of metal without having the small cut/break there.
Yes I know, that if this is a sheet with not to much thickness YOu will bend it anyway, but the geometry there will not be really defined or ruled.
And this is, what a computer needs to do, hold on rules!
The reason I want this design is to simplify the punching to a single cut(chamfer) around the corner.
This would also give the best weld space results for a seal welded tank if this was the lid inserted inside.
The small slot is not part of the desired result for automating exports of flat patterns to nesting software.
The only problem is CAD does not want to work the way our shop actually makes things. In real life, sheet metal does bend in two directions. Even if it is just for a small bit of the metal around a 2 way or 3 way corner.
I was thinking that there was a way to use surfaces, then enclosed surfaces to create a solid, then add that solid to the sheet metal flat pattern. This in turn would require the flat to be calulated from polygons rather than typical sheet metal unfolding.
So, if you're wanting to generate your flat pattern off of your Solid Model, then why model this with the flat pattern driving it and not just model it in 3D from the start? I bet you'll get better end results that way.
Hi @12GAGE, to understand a little better the bending techniques they use, it would be very useful to provide us with a couple of images (if you can) so that we can probably provide a better alternative to the design.
I don't care if the part is made from flanges or from added bends. No matter how the part is made, the same problem remains. I cant cut the flat with a 45 deg cham across the seam of the close corner.
Right now we use one or two rectangular notches that requires more programming, punch time, tool wear, etc.
Attached are screen shots of the designs I want to use the chamed close corner for. This would clean up the welding gaps.
Here is a link to look at some typical products