simple(?) solidworks sheetmetal problem

This should be an easy problem, however i'm a newbie and can't figure
it out. Thanks in advance for any help on this. Here's the problem:
I shelled a rectangular solid to make it into a sheetmetal part. There
will be 4 flanges along the top so that a separate lid will rest flush
against the flanges. What should i do about the four corners so the
flanges don't interfere with one another? There will be screws located
at the four corners securing the lid, so it seems that any diagonal
flange cuts at the corners wouldn't work. ??

 

You should have created a base flange and then added a miter flange.

 

fyi, thin-extrude or base flange are the preferred methods for creating
sheetmetal parts. shelling a solid is a last resort method.

after which, use an edge flange, then edit sketch, pull back the ends of the
flange.

reference my crude ascii art.
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| o |_________
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If you use a miter flange, it will take care of all the corners for you. If
you need an example, let me know.

WT

 

downside with mitre, cannot put fastener in corner as requested.

 

Ahhh, missed that point.

I would probably go with an extruded base with the 2 sides, then edge flange
the 2 ends.

Or, can the fasteners be moved a bit so that the diagonal joint of the miter
flange not get in the way?

WT

 

Hi Jay -

I made you a sample model. What you want to do is pretty straight
forward.

You can make a shell and then sketch your top lip on the upper rim of
the shelled box.

You can make the miter cuts if you want or have a straight edge. There
are no perfect options. I drew one of them to give the basic idea.

There are lot's of ways to do this and get good results, so don't let
the newness of it all stop you from trying different methods: Here is
one way using the Insert-Bends method:

http://www.sheetmetaldesign.com/Cad-SolidWorks/Example22-ShelledBoxWithTopFlanges.zip

Also note - this type of part is hard to tool sometimes, especially
when the dimensions are as I drew it. If it is done in a brake press,
2 of the sides are simple to form, the third is a bit challenging, and
the 4th an absolute nightmare. When making a box with a top rim, I
always try to consider the last formed edge and ask myself if the
forming punch will be able to come out of the box. Food for thought.

Later -

SMA