"Chew the Fat" or "Chew the Rag" are English expressions for gossiping or making friendly small talk; the former being mainly in the American vernacular or common speach.
Some sources attribute the phrase, Chew the Fat, to sailors, who during a period of resting and conversing, or while working together, would chew on salt-hardened fat, there are no reliable historical recordings of this practice. It has even been suggested that the phrase is derived from a practice by North American Indians or Inuit of chewing animal hides during their spare time, and even of British farmers chewing on smoked pork, but again, there remains to be no evidence supporting these claims, and would requires accepting a great deal of uncertainty in connecting the phrase from nautical origins to its modern metaphorical use.
Chew the Rag first appeared in print in 1875 in "Random House Historical Dictionary of American Slang"; "Gents, I could chew the rag hours on end, just spilling out the words and never know no more than a billy-goat what I’d been saying." It is speculated that this phrase is related to cloth, when ladies would work in "sewing circles", or that women may have gossiped while quilting.
Chew the Fat first appeared in 1885 in a book by J Brunlees Patterson called Life in the Ranks of the British Army in India. He implied it was a kind of general grumbling and bending the ears of junior officers to stave off boredom, a typical part of army life. Patterson also uses Chew the Rag in the same sentence he used Chew the Fat,