Rope Float

Simple design to prevent dock lines, anchor rodes, bridles, etc from sinking.

Two identical models are pre-scaled for for ½" and ¾" ropes.

Open-source and fully customizable, created using ShapeScript.

Printing

Should be printed with as little infill as possible to keep it light, but with thick walls to ensure it stays relatively strong and waterproof.  It's always a good idea to paint it, or cover in some UV-stable resin after — to ensure it remains waterproof and doesn't let mold or dirt get attached to it too easily.

As for the filament, it's ideally something UV-resistant, bright-colored, maybe glow-in-the-dark.  Might be a good case for using foaming filaments.  Many materials deform in the sun, hence need to use something other than conventional PLA.

Minimal layer height is always a good idea — in this case, to avoid chafing of the line.