The Whitworth Brothers established a successful lumber milling operation in Avinger that would last for more than twenty years. Fred McKenzie noted the Casey-Pruitt-Whitworth lumber mill at Pruitt's Lake in Cass County. The mill burned at “Barne's Lake,” according to McKenzie; this may have been a misprint for Pruitt's Lake.They established a mill town, which they supported with a commissary. They began with the old A. M. Rhyne planer at the southwest end of town and moved it four miles north of town. Will Powell served as the planer foreman. This planing mill was later passed on to E. C. Henderson (see Henderson).
By the later 1920s, the mills could manufacture 60,000 feet of lumber and finished products daily. Whitworth Brothers were not listed in the Lumbermen's Credit Rating Book of October 1934.