Design Articles

TECH TOPICS:

Balance by T.J. Perrotti

A discussion of the forces that act on a boat―above and below the waterline―while it is sailing.

Positioning the Ballast by John Henderson

The Effects of Being Overweight (your boat that is) by John Henderson

Running Backstays by Gudmund Thompson

Setting Up Swing-Arm Sail Controls by John Henderson

Helm Balance, with simple calculations of Center of Effort and Center of Lateral Resistance by John Henderson

Speed by John Henderson


Computer Radio Use in R/C Yachting by Gudmund Thompson

This article explores the capabilities of a modern computer-based radio with several increasingly complicated scenarios including overlapping headsails and running backstays.


Planning and Building Scale Models that Sail by John Henderson

Scale models of full-sized boats should look realistic and sail well. These two goals have more or less equal importance, but they can conflict. So we must address the trade-offs, which imposes some practical limitations. This three-part series of articles will introduce you to the considerations and calculations needed to create a sailing model from full-sized plans.

Part 1: Implications of Scale and Model Choices

Part 2: Design Calculations

Part 3: Building


Rating Rules for Vintage Models by John Henderson

Rating rules attempt to quantify and balance the speed-producing aspects of a design against those that generally slow it down. This article describes rating rules that embodied our hobby’s early attempts to rate disparate models.


Is the Ideal Rating Rule Possible? by J.G. Feltwell

In this article from 1929, a Naval Architect discusses the effects that different rules and rule types have on boat design and tries to answer the question in the title.


Modeling a Historic Chesapeake Bay Log Canoe by John Henderson


Taking the Lines off of Scat II, a Previously Unknown Design by John Black by Earl Boebert

This article describes a photographic method for taking the lines off of a historically significant model.


Speaking of Batteries by John Henderson 

Selecting the right battery for your R/C model.


Prospero by W.J. Daniels (1912)

The great British designer W.J. Daniels produced uncommonly handsome boats including this schooner, named for the sorcerer in Shakespeare’s play The Tempest. He was a pioneer in developing methods to achieve what is now known as hull balance. A balanced hull is one that does not yaw, or turn, when it heels under a gust of wind going to windward.

More on Prospero by Earl Boebert, Russell Potts, Art Holzman

Reader comments inspired by the Prospero article above.


What a Difference a Year Makes by Earl Boebert

This brief article compares the design of Wampum (1932) and Wampum II (1933). The contrast between the two boats illustrates the rapid evolution of the Marblehead class in its earlier years.


Traditional Model Yacht Design by Thomas Moore

This article is excerpted from Thomas Moore´s Build a Winning Model Yacht, published in 1928. Moore was a naval architect and this work captures the state of model yacht design in the 1920s.


Curve of Areas, Versed Sines, Trochoids, and the Wave Theory by Earl Boebert

In 1877, Colin Archer proposed his “Wave Theory” of displacement (non-planing) hull design. This theory was based on an important concept called the curve of areas.


That Peculiar Property: Model Yachting and the Analysis of Balance in Sailing Hulls by Earl Boebert, presented at The 18th Chesapeak Sailing Yacht Symposium, 2007

Balance in sailing hulls has been most extensively studied by the designers of free sailing model yachts. This paper describes the nature of free sailing which led to this preoccupation, and then explains the controversial theories of Admiral Turner. the correlation between Turner’s criteria for balance and know balanced and unbalanced designs is shown and procedures given for designing boats to those criteria. The paper concludes with speculation about the relationship between theory and practice in this area and suggests areas for further research.


Sail Plans: Dimensioned and Balanced for the Marblehead Class Racing Yacht

A treatise on proportions of sails for the Marblehead class of boats.