Merged Lines after Grouping

I have seen a few older post about this issue, but wanted to see if there was any new input on how to fix this issue.  I grouped multiple objects and although they appear to line up properly they leave lines when they merged.   I understand that if I have a bit of overlap the lines don't occur, but it was not possible with the objects I had and my skill level...    I also understand they will probably not affect the print, but it does effect the cleanliness of the rendered preview images, make the object look unclean.  


Please sign in to leave a comment.