Thanks Peer I tried to simplify the shape as the outer shape can either sqr or round ultimately the machine doesnt know which tool set you put in but still same problem - here is another part created in MOI with essentially the same components a few 90 degree bends - a few straight sections and 1 large arc this file imports into the tube bend software without problems - strange that it work most of the time but with the occasional file its a no go - Ill keep experimenting see if I can pinpoint the issue.