Take a strip of bacon out and do an initial measurement. Wrap it around the cob with about 1 1/2 inches to spare. The bacon will shrink as it cooks, so make allowances for this. Now, take 3 slices or so, cut to the right measurement. Lay them flat and season with some chili powder and black pepper. Begin rolling cobs and secure with 1-2 toothpicks. Cut away and straggling edges Continue doing this for the remaining cobs.