I do some simple dwg output of sheet metal parts for a customer that uses a nesting program for plasma cutting.
On simple parts that won't need bending, I open a dwg into a slddrw using the option "Convert to Solidworks Entities".
After making changes, I output from the slddrw as a dwg. I could do this in a 2d editor, but I'm more accustomed to using swx, and 90+% of the time this procedure works fine.
Occasionally, the customer's nesting program will show an open profile error on the geometry.
On my machine, while in the slddrw, chain selecting shows a good profile.
The only way I've found to work around this is to import the same dwg again, but instead make a sldprt and extrude the sketch, make a new slddrw from the solid, and export again as a dwg. No geometry was touched during this procedure, but nearly always, the nesting program will then be OK with the new dwg file.
I'm using swx2010 sp3.1 on a vista machine, sp4.0 on an XP machine, and I saw this same issue on swx2006 that I was using a while back.
Is there any settings in swx that could affect the merging accuracy of entity endpoints, etc when working 2d in slddrw files?