Topics: Scale conversions (math); Maritime history
Wooden ship models or wooden model ships are scale representations of ships, constructed mainly of wood. This type of model has been built for over two thousand years.
The ship: HMS Victory
She is a 104-gun first-rate ship of the line of the Royal Navy, ordered in 1758, laid down in 1759 and launched in 1765. She is best known for her role as Lord Nelson’s flagship at the Battle of Trafalgar on 21 October 1805. In 1922, she was moved to a dry dock at Portsmouth, England, and preserved as a museum ship. She has been the flagship of the First Sea Lord since October 2012 and is the world’s oldest naval ship still in commission.
My father grew up on Boston Harbor. In addition to being a soldier, and an engineer with a research think tank, he did ship modeling at the USS Constitution Museum.
In the USS Constitution Museum workshop, 1990’s.
A model of The US Navy Schooner Enterprise
The third ship to be named USS Enterprise was a schooner, built by Henry Spencer at Baltimore, Maryland, in 1799. It was overhauled and rebuilt several times, effectively changing from a twelve-gun schooner to a fourteen-gun topsail schooner and eventually to a brig.
The Flying Fish
The Flying Fish
The last model ship hull that my father,ז״ל, was working on.
Scale conversion factors
Written by George Kaiser (later incorporated into Wikipedia)
Instead of using plans made specifically for models, many model shipwrights use the actual blueprints for the original vessel. One can take drawings for the original ship to a blueprint service and have them blown up, or reduced to bring them to the new scale.
For instance, if the drawings are in 1/4″ scale and you intend to build in 3/16″, tell the service to reduce them 25%. You can use the conversion table below to determine the percentage of change. You can easily work directly from the original drawings however, by changing scale each time you make a measurement.
|from||to 1/8||to 3/16||to 1/4|
The equation for converting a measurement in one scale to that of another scale is D2 = D1 x F where:
D1 = Dimension in the “from-scale”
D2 = Dimension in the “to-scale”
F = Conversion factor between scales
Example: A yardarm is 6″ long in 3/16″ scale. Find its length in 1/8″ scale.
F = .67 (from table)
D2 = 6″ X .67 = 4.02 = 4″
It is easier to make measurements in the metric system and then multiply them by the scale conversion factor. Scales are expressed in fractional inches, but fractions themselves are harder to work with than metric measurements.
For example, a hatch measures 1″ wide on the draft. You are building in 3/16″ scale. Measuring the hatch in metric, you measure 25 mm. The conversion factor for 1/4″ to 3/16′, according to the conversion table is .75. So 25 mm x .75 = 18.75 mm, or about 19 mm. That is the hatch size in 3/16″ scale.
Conversion is a fairly simple task once you start measuring in metric and converting according to the scale.
There is a simple conversion factor that allows you to determine the approximate size of a model by taking the actual measurements of the full-size ship and arriving at a scale factor. It is a rough way of deciding whether you want to build a model that is about two feet long, three feet long, or four feet long.
Here is a ship model conversion example using a real ship, the Hancock. This is a frigate appearing in Chappelle’s “History of American Sailing Ships”.
In this example we want to estimate its size as a model. We find that the length is given at 136 ft 7 in, which rounds off to 137 feet.
|1/8 scale||Feet divided by 8|
|3/16 scale||Feet divided by 5.33|
|1/4 scale||Feet divided by 4|
To convert feet (of the actual ship) to the number of inches long that the model will be, use the factors in the table on the right.
To find the principal dimensions (length, height, and width) of a (square rigged) model in 1/8″ scale, then:
Find scaled length by dividing 137 by 8 = 17.125″
Find 50% of 17.125 and add it to 17.125 (8.56 + 17.125 = 25.685, about 25.5)
Typically, the height of this model will be its length less 10% or about 23.1/2″
Typically, the beam of this model will be its length divided by 4, or about 6 1/2″
Although this technique allows you to judge the approximate length of a proposed model from its true footage, only square riggers will fit the approximate height and beam by the above factors. To approximate these dimensions on other craft, scale the drawings from which you found the length and arrive at her mast heights and beam.
Reference: Williams, Guy R. The World of Model Ships and Boats London 1971 Page 30
We are the largest model ship association on the East Coast and our friendly meetings overlooking Old Ironsides at the USS Constitution Museum are well attended. Novices and experienced model builders alike can have fun developing resources, experiences, and skills by joining us.
The USS Constitution Museum serves as the memory and educational voice of USS Constitution, by collecting, preserving, and interpreting the stories of “Old Ironsides” and the people associated with her.
Ocean Literacy The Essential Principles and Fundamental Concepts of Ocean Sciences: March 2013 and Ocean Literacy Network. The Centers for Ocean Sciences Education Excellence (COSEE) and Lawrence Hall of Science, University of California, Berkeley
Massachusetts History and Social Science Curriculum Frameworks
5.11 Explain the importance of maritime commerce in the development of the economy of colonial Massachusetts, using historical societies and museums as needed. (H, E)
5.32 Describe the causes of the war of 1812 and how events during the war contributed to a sense of American nationalism. A. British restrictions on trade and impressment. B. Major battles and events of the war, including the role of the USS Constitution, the burning of the Capitol and the White House, and the Battle of New Orleans.
Time, Continuity and Change: Through the study of the past and its legacy, learners examine the institutions, values, and beliefs of people in the past, acquire skills in historical inquiry and interpretation, and gain an understanding of how important historical events and developments have shaped the modern world. This theme appears in courses in history, as well as in other social studies courses for which knowledge of the past is important.
A study of the War of 1812 enables students to understand the roots of our modern nation. It was this time period and struggle that propelled us from a struggling young collection of states to a unified player on the world stage. Out of the conflict the nation gained a number of symbols including USS Constitution. The victories she brought home lifted the morale of the entire nation and endure in our nation’s memory today. – USS Constitution Museum, National Education Standards
Cite strong and thorough textual evidence to support analysis of what the text says explicitly as well as inferences drawn from the text.
Determine the meaning of words and phrases as they are used in a text, including figurative, connotative, and technical meanings
Use words, phrases, and clauses to link the major sections of the text, create cohesion, and clarify the relationships between claim(s) and reasons, between reasons and evidence, and between claim(s) and counterclaims.
Establish and maintain a formal style and objective tone while attending to the norms and conventions of the discipline in which they are writing.
Produce clear and coherent writing in which the development, organization, and style are appropriate to task, purpose, and audience.