I don't have any Ody, but I have a Penelope and use it in that. The number of strands you use really depends on the coil you make. Because the threads swell with juice, you don't want your wick to be tight in the coil when it's dry. I wrap my coil around a nail and then pull six strands through the coil. That way I can't wind the coil too tight. On my A7 I wrap around the inner hook of a paper clip and make a flat coil, and pull 10 threads through.
The problem I had with my Penny using the strands of string was the wire that wasn't connected to the post kept wanting to pop up through the threads which would cause a short if not completely covered. I couldn't get that wire to lay flat to save my life. I now use a braided cotton strand that fits in the grooves perfectly. I also got a sample of hemp rope that will fit perfectly in the grooves but I haven't tried it yet.