mechinacal rights differ from publishers rights as they refer to the acual production of the music in question .securing your mechinacal rights requires you to have either a publishing deal or a recording contract. if you have a recording contract often the company will attempt to have you sign a 3/4 mechinacal rights deal to cover breakage (really give aways/returns lost items etc)if you havent actually recorded your own songs for another label then mechanicals mean nothing (the artist who recorded your song would get the mechinacal )