Dear Mr. Miller,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog but were unable to locate records about a barge, on which John McDonald sailed that sank in the Great Lakes in 1933 or any records about Frank McDonald missing that same year in the Records of the U.S. Shipping Board, 1914 - 1939 (Record Group 32) or the Records of the U.S. Maritime Commission, 1917 - 1950.
Therefore, we suggest that you search the List of shipwrecks in the Great Lakes for the ship that John McDonald and Frank McDonald may have sailed on before the barge or vessel that sank or contact Great Lakes Historical Society for more information or research tips.
We hope this is helpful. Best of luck with your research!