I have ensured no naked edges, used MatchSrf on any that showed. then used Join. Checked again no naked edges.
OffsetSrf 2mm and I get a 1mm split in one part of the model.
However run MatchSrf and it wont select anything.
Explode the model and still MatchSrf wont select anything.
JoinEdge will , dead easy. but one must never use that command.
How do I fix the little crevaces that OffsetSrf 2mm has gone and caused, and this not so little one, as is its habit ! The starting shape was a fine piece of work but offsetSrf will wreck things.