Frank reenlisted (having previously served in the 11th Maine Infantry) for three years at Augusta, Maine as a private in Company I, 7th Maine Infantry on June 22, 1864. Because the 7th Maine Infantry had lost so many men due to battles and disease, it was consolidated with men from the 5th Maine Infantry and 6th Maine Infantry whose enlistments had not yet expired. The new regiment was designated the 1st Maine Veteran Infantry Regiment. Frank was transferred to Company I on August 21, 1864. He mustered out with the regiment in Washington, D.C. on June 28, 1865.