Make sure that you use rope light enough to break by cranking the big motor if chains get hung . We went after a boat that sunk on Enid around sign 13 because he could not break a big rope and did not have time to find a knife by the time he realized he could not get it free from a stump . The old man I used to fish with used window weights . He also took schedule 40 PVC (1 1/2 ) filled with concrete with an eye bolt in one end . Said that he had rather wash off pvc than deal with muddy/ rusty chains .Food for thought .