Model Shipways Ratliner - The Shroud Building Tool - For Approximate Scale of 1:35 to 1:48 A Ratline is a nautical term used to describe a rope ladder upon which sailors scampered up to the lower yards to furl or unfurl sails. The Ratline usually stopped at the lowest yard and from there a “Jacob's Ladder (also made of rope) was used to get to the higher yards and the top of the mast.