We have a network with a central print server, which shares printers with connected Ubuntu clients automatically via CUPS browsing. That means every Ubuntu client gets the full printer list automatically. Windows clients use Samba to print over this machine. Works pretty well.
Now, there are some machines with local printers. These need to be shared, too, for Windows and Ubuntu clients. However, when creating a smb.conf with a printers share, this share contains not only the local printer, but also all other printers found via CUPS browsing. I need to create a special printer share instead, explicitly using "printer name" to specify the local printer. This is, IMHO, not expected behaviour, and should be changed.
this is how it's designed to work. Some thoughts: either configure the smb printer on the central print server, where you can also configure cups to print to another cups server - or disable printer discovery on the client machine, where you don't want the other printers to be visible. In any case this is something special, nothing that samba will be able to take care of.