Skeg-hung rudder — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/skeg-hung-rudder/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
Catalog version: 2026-10-20

Sizes: see table below
- A skeg ahead of the rudder supports a lower bearing, protects the blade and helps tracking; because the skeg sees a lower angle of attack, the combination stalls later than a spade (Good Old Boat).
- A full skeg leaves no balance area, so helm loads get high on big boats; Perry's compromise is a half-depth partial skeg.
- The file is a reference example built by Xem Studio from the numbers above (Illustrative.). Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

parameter  value or range  source
Partial skeg  about half rudder depth (Perry)  Good Old Boat
Upwind weather helm optimum  2-4 deg  Good Old Boat

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Good Old Boat: The rudiments of rudders — web — Publisher's page; dimensions are facts — https://goodoldboat.com/the-rudiments-of-rudders/

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/skeg-hung-rudder/index.json
API: https://xemstudio.com/api/geometry?object=skeg-hung-rudder