How do I convert an NX Nastran model with contact to MSC Nastran?

MSC input is a bit different, but it’s not to hard to convert the input file with a text editor:

BCBODY1Defines deformable bodyReferences BSURFCreate a separate BCBODY1 for each BSURF. To keep it simple, use the same id as the BSURFBCBODY1,id,,2D or 3D,,bsurf-id
BCTSET or BGSETBCTABLE1/ BCONECTDefines connection between bodiesBCONECT references BCONPRG/BCONPRP, BCTABL1 references individual BCONECT contact pairsBreak BCTSET/BGSET up into individual pairs to convert to BCONECTs. This uses the ids of BCBODY1, not BSURF. If you used the same ids for BCBODY1 as BSURF, then you shouldn’t need to worry about ids. Give each BCONECT pair an ID. Create a BCTABL1 that lists the ids of the BCONECT pairs. If you have friction, that needs to go on the BCONPRP, which is otherwise optional.BCONECT,pair-id,bconprg-id,bconprp-id,slave-id,master-idBCTABL1,table-id,pair-id1,pair-id2,pair-id3,etc.
BCRPARABCONPRG/ BCONPRPDefines top/bottom and offset for NXBCONPRG,id,,IGLUE,3 turns on glued contact for the BCONECT.BCONPRP,id,,FRIC,value turns on friction for the BCONECT.BCONPRG also has options for top vs. bottom face, and shell thickness
BSURFBSURFDefines elements that make up contact surfaceNo change neededNo change needed