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In some of the tables of rigging sizes, based on main stay size or mast diameter, he sometimes says things like ".016%" when he really means "16%".  Or he sometimes isn't clear whether he's specifying diameters or circumferences of ropes or spars.  It's usually circumferences.  (Obviously, if he's talking about relationships between two spars or two lines it doesn't make a difference). If you work through some of the examples it usually becomes obvious.

 

In sail rigging he's not clear whether some lines are on both sides of a sail or just fore or aft.

 

Otherwise most of the book is very useful.  Mine is worn out after only one build!

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Posted (edited)

ah100m is correct about the circumference error in Mondfeld's tables on rigging size. Everything is based upon the mast diameter, but the resulting rope sizes often are given in circumference! The relationship is the main stay circumference is 0.166 the diameter of the mast at the partners (at the deck). I am sure this confuses all novice modelers - it had me going in circles for a while!

 

CORRECTION: It certainly is confusing, and tripped me up again! Mondfeld says the thickness of the stay is 0.166 (or 16.6%) of the mast diameter. Corrections below are in bold type.

 

Rope circumferences are then given as percentages of the main stay circumference ( or the fore stay for two masted fore topsail schooners). This is common in every text I have seen, going back into the 1700s. But you must use the same units of measure (inches, centimeters, etc.). So if the mast diameter is in inches the circumference will be in inches. And if you really want to get picky, remember English feet were not the same as French, Dutch or Swedish feet (before they changed to the metric system). The differences are small and can be ignored for model rigging diameters/circumferences.

 

However, for wire rope that began appearing in the last half of the 1800s the formulas are different - basically about 33% of the rope circumference as Mondfeld says. But this is just an approximation.

 

Circumference = pi x diameter, or C = 3.14159 x d. So the diameter of the stay is the stay circumference divided by pi (3.14159):

 

Mondfeld says mast diameter x 0.166 = stay circumference thickness (diameter)

 

stay circumference = stay diameter x pi.

 

stay diameter = (mast diameter x 0.166)/3.14159 = mast diameter x 0.0528

 

So the stay diameter is about 16.6% of the mast diameter. For a 24 inch diameter mast the stay will be about 4 inch diameter.

 

Since model rope and thread sizes are usually given in diameters it is best to calculate the stay diameter and work from that.

 

After you get the stay diameter the percentage ratios in Mondfeld's tables apply to all other rigging diameters. However, there are other rules that give slightly different results, depending upon nationality and period. And almost none of these rules apply to schooners and other fore and aft rigged vessels.

 

****

 

I don't know that there are any outright errors in what Mondfeld says. He gives general rules for different periods and nationalities that I am certain were right for some vessels. But if there is anything I have learned it is that no rule applies all of the time for any period or nationality. A great deal of leeway was given to ship builders, owners and Captains for how a ship was constructed and  rigged, and it could change with time. It is certain that some vessels were built and rigged differently from what Mondfeld shows, but since no two vessels were ever exactly alike, this is not Mondfeld's error. Just take what he says with a grain of salt, and if you cannot find accurate period plans for the ship you are building, Mondfeld's "rules" are as good as any other.

 

I have compiled just about all the rules I can find in the spreadsheet in the discussion in this link about topsail schooner rigging (post #57). The spreadsheet compares the different rules and shows the slight differences. Most of the rules are for full rigged ships but there are some for schooners. Then a separate section calculates the sizes of ropes for schooner rigging based upon a mast size you provide.

 

The thread also gives definitions of sail and rigging terminology, and the basis for calculating many of the dimensions of ships.

Edited by Dr PR
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Good Morning Phil;

 

I am somewhat confused by the proportion given above of 0.166, as this does not seem to make any sense. 

 

For example, a 12" mast, multiplied by 0.166 = 2", which, if this is the circumference, will require a rope only 5/8" in diameter. I cannot believe that any mainstay for a 12" mast would be this size (unless it is wire?)

 

As a check, the mainstay of late 17th century Royal Navy warships had a circumference which was close to 0.5 the diameter of the mast. So a 24" mast would have a stay of approximately 12" circumference, giving a stay of 3 3/4" diameter. This is approximately 15% of the mast diameter, not 5%.

 

Can you clarify this in any way, as something is clearly amiss. Your earlier posts, and all your work, on schooners is all so thorough, that I can only suppose that you have had a moment's memory lapse when giving the proportional figure above; or the explanation is in error (or that I am!)

 

All the best,

 

Mark P

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Posted (edited)

Brett, what ship are you working on? 

A quick fix is do not use Mondfeld and get a copy of Lees' Masting and of Rigging English Ships of War1625 to 1860. In appendix 1 He begins with the length and breadth of the vessel.  The initial formula varies a bit depending on the year the vessel was launched.  The dates he uses are 1627 to 1669, 1670 to 1710, 1711-1718, 1719 to 1772, 1773 to 1793, 1794 to 1814, 1815 to 1835, 1836 to 1860.  

 Once you have the length of the mast from the initial formula, it goes to mast,  yards, sprits, and boom diameters, then lengths, then standing and running rigging.  He ends with block sizes.   There are 7 pages of formulas/ratios and is quite complete.  As Mark points out above, a lower mast with a diameter of 24"  has a lower stay that is 12" in circumference.  

There is also the same information here at MSW for free, and with one time period exception it is more accurate than Mondfeld.  This is a spread sheet by Dan Vadas  in the articles data base.  Caution here though.  While he used the formulas from Lees and made an easy to use spread sheet,  his initial formula for the masts' lengths for the period 1670 to 1710 is completely wrong so everything that follows is wrong as well for this time period.     Lees book would be the go to for this time period.  If anyone has access to the original spread sheet done by Dan, it should not be too hard to fix this time period with the correct formula.  

 

For rigging details in general, Lees has been my go to for a long time as it is well written and has detailed drawings to go with the text.

 

Allan

Edited by allanyed
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And back to the original question: Mondfelds book is quite old. Dating abck to the sixties. Back than it was one of the few reasonable priced sources available to modelers.

 

What I do not like about Mondfeld is that he does not give any sources for what he presents: it is not easy to use his book as an 'entry' to the more detailed literature. 

 

Jan

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Omissions and lack of source citations aside, I think it is still the best handbook on ship modeling for beginning and intermediate ship modelers.

 

Eventually, one may "graduate" to various sources for more specific details. But, if I were to hand a promising ship modeler one book to help him or her out, it would be this one.

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Mark,

 

You are right, I should have checked the 0.166 value with other formulae. The stay diameter I calculated did seem rather small!

 

Using a main mast diameter of 24 inches here are the main stay calculations.

 

Mondfeld says the thickness (diameter) of the main stay should be 0.166 x mast diameter.

 

(Note: my error above. Mondfeld is talking about stay diameter, not circumference)

 

24 x 0.166 = 3.984 inches

 

Circumference would be diameter x pi (3.14159)

 

3.984 x 3.14159 = 12.516 inch circumference

 

Lees says something (undefined) is 1/2 the mast diameter. Assuming he meant circumference,

 

24/2 = 12 inch circumference

 

So there is a 4% difference between Lees and Mondfeld. For modeling purposes in all but the very largest scales this difference is insignificant.

 

Both Lees and Mondfeld give data for large three masted square riggers, but it is all useless for schooners and other fore and aft rigged vessels.

 

Some of the difference between Lees and Mondfeld lies in slight differences in calculations for mast length and diameter. Lees' (The Masting and Rigging of English Ships of War 1625 - 1860) calculations are specific for full scale English warships and Mondfeld's (Historic Ship Models) are more general and apply to a range of warship and commercial vessel models. Comparing them is like comparing apples and oranges.

 

****

 

Everyone raves about Lees but all through the book he fails to say what he bases his dimensions on. All mast and spar dimensions are based upon a hull length or beam, but he doesn't say if the hull length is the Line of Flotation, distance between perpendiculars, or length on deck. All three different values are used by other authors, and they usually say which they use. The difference between these lengths is significant. We are supposed to guess what Lees is talking about?

 

Furthermore, although he does define the "hounds length" he doesn't say what the "hounded length" is that mast dimensions are often based upon - but this is common to most authors. We are just supposed to know if it is to the top of the hounds, the bottom, and whether the length is from the foot of the mast or the partners, or something else entirely. Underhill is the only author I have found who says explicitly the the "hounds" is the flat the cross trees rest on, and the hounded length is from the foot (the very bottom of the mast) to the hounds.

 

Lees also used the "length of the mast" but never says if it is the measured length, hounded length, deck to top or deck to hounds. All four lengths are used by other authors in different periods and they are significantly different. Again, are we supposed to read his mind?

 

There are other places where he fails to define the basis for his statements. We are just supposed to know what he means I guess, and this is VERY frustrating to someone who doesn't already know all the answers. I have spent many hours doing calculations based upon the representative tables to back calculate to try to figure out what he is talking about!

 

These errors are characteristic of someone who is functionally illiterate - incapable of understanding how to communicate the things he knows to people who do not already know. But this is a common characteristic of many authors.

 

And a common problem I see on this forum is that different people assume they know what he is talking about without realizing their assumptions are just one of several possibilities. So they make pronouncements based upon their interpretations that often are questionable.

 

****

 

Having said this, I do think Lees is an excellent reference. His drawings are superb and he gives a lot of actual ship data for English square riggers. But you have to do a lot of reading between the lines to figure out what he really is trying to say. For other nationalities and types of rigs you must look elsewhere.

 

And as for statements that Mondfeld's (Peterson's, etc.) books are full of errors, these are always unsubstantiated. Rarely does anyone say what the errors are, and in some cases the criticism is based upon knowledge of a single vessel that differs from the author's description of another vessel. One thing I am certain of is that no two ships were exactly alike, and even a particular ship may have changed over time. And it is a fact that the records for historical ships are almost always incomplete, so a lot of guesswork is necessary.

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One has to wonder, how many ships were rigged and fitted according to Lees vs  how much of Lees was compiled from data of ships having already been rigged and fitted by the craftsman of the time?

 

In other words, Lees merely documented " .. how it should be done, because this is how it is/was done.  "..

 

Not unlike Petersson documenting how a particular model was rigged..

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To my knowledge Lees reviewed the literature and the models of the time. With models of the time it is always an uncertainty, if and when they might have been re-rigged or 'restored', of course. However, these are the best guesses we have.

 

Books that cover a too wide range in time and geography are always problematic, because they will lack in depth and thoroughness - due to the limited knowledge of the authors and constraints imposed by the publishers (who are only interested in what sells, not what might be useful for a small group of afficionados).

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First, no book is entirely error free! It's not, alas, an ideal world we live in. The further we get historically from what we are trying to study, the harder it becomes. 

 

There is also a great difference between primary and secondary sources.

 

Primary evidence comes from the time and place of the subject we are studying. Whoever wrote, produced an artifact  or model is likely more reliable a witness to how things actually were. In the case of a model, things might be stylized or simplified, so one needs to be careful.

 

Secondary evidence is from a later time and place. The creator may draw lightly or heavily on primary sources, but transcription and interpretational errors can creep in. As a history research professional friend observed; "Read elsewhere and read critically, always." He is so right!

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Posted (edited)

 

On 6/20/2021 at 3:04 AM, Dr PR said:

Everyone raves about Lees but all through the book he fails to say what he bases his dimensions on. All mast and spar dimensions are based upon a hull length or beam, but he doesn't say if the hull length is the Line of Flotation, distance between perpendiculars, or length on deck.

Phil, Not sure I agree on this comment.    For length of masts Lees does indicate if the formula to use for a given time period is based on length of the keel and beam and depth of the ship,  length of the lower gun deck,  or the beam on page183.    These initial dimensions are readily available on many, if not most contemporary drawings with actual figures given or a scale on the drawing.  He is specific about the length of the mizen being from the step in the hold and how to adjust if stepped on a deck above the hold.   I may be wrong on this, but I believe it follows that the lengths for the fore and main masts are from the step as well.  I have checked contemporary rigging drawings and these indicate that my assumption is correct.   For one example, the contemporary rigging drawing of a 90 gun ship of 1745 from NMM  has the main mast from the step to the top of the mast as 110 feet.   The beam of 1741 proposals for a 90 gun is 48 feet.  Using Lees' formula for this time period, 48X2.28 = 109.44 feet.  Several third rate and 6th rates that I checked are similarly close.    

 

He does state that the dates he has chosen in the appendix are conjectural, but that they are based on various contemporary  drawings,  models and published contemporary works including those by Manwaring, the Admiralty list of 1640, Sutherland and et al.

 

The forward by Alan Villiers and the Introduction by Lees gives a good amount of his CV and a list of his sources for various time periods.  

 

Cheers

 

Allan

 

 

Edited by allanyed
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Posted (edited)

Allan,

 

You are correct - Lees does give detailed descriptions of the "length" of the main mast relative to hull dimensions on page 183, and I have no doubt that he researched this well.

 

But what "mast length" is he specifying? I did see where he was using a length measured from the step on the keel, or the foot of the mast. But I have read through the book several times now and cannot discover if his mast length is the hounded length (from the foot to the hounds - cross trees) or the "measured length" from the foot to the top (top of the top cap) - the actual length of the entire pole or mast structure.

 

So the question is whether his "mast length" includes the top (measured length) or does not (hounded length). Since mast diameter and spar dimensions are usually based upon "mast length" and rigging diameter/circumference is based upon mast diameter, virtually every dimension in the masts and rigging depend upon this question.

 

Lees says the mast head length varied over time from 3.75 inches to 6 inches per yard of main mast length, or from 10% to 16.7% of the mast length. The difference between hounded length and measured length was 10% to 16.7% of the "mast length" and this will give proportionate differences to the calculations of everything else in the masting and rigging. This is a possible error of 1 in 6 to 1 in 10 in all calculations if we assume one mast length and it was actually the other he was talking about.

 

However, he does give the diameters of all parts of the mast from the foot to the top on page 2, and I suspect he is using the measured length. But it would have been nice if he had stated unambiguously what he meant by "mast length."

 

As I said, Lees book is a valuable reference, but this one omission greatly reduces it's reliability for mast and rigging dimensions.  But Lees certainly isn't the only author to make an important omission, assuming that the reader will know what the author meant!

Edited by Dr PR
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Posted (edited)

Phil,

I suppose the best thing we can do is hopefully find an appropriate contemporary rigging drawing for a specific ship or at least one that is of the same era and same rate as one's project.   There are not nearly as many of these drawings as there are the typical deck, body, and profile plans that still exist.   I just looked at Deane's Doctrine of Naval Architecture  explanation of the length of the masts, and  Lees' formula is of course identical for this time period.  But, as you have pointed out, there is no mention of where the top is measured, at the hounds, the cap or somewhere else in either Lees' or Deane's books, at least that I could find.  I am going to try to find enough rigging plans to make a reasonable study and download them to see if there is any consistency in where the measurements take place.  

Hopefully it will give all of us some base from which to work.

Allan
 

 

Edited by allanyed
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I found rigging plans for a 24 gun 6th rate, 50 gun fourth rate, 80 gun 3rd rate, 90 gun 2nd rate and 100 gun first rate on the NMM site.  All are from 1745.   I inserted each into TurboCad and enlarged to full size using the scale on the bottom of each drawing.    I then checked the height of the main masts  on the drawings from the bottom of the mast inside the step to the top of the mast at the top of the cap, in other words, the entire length. Keep in mind the drawings were low resolution but when scaling to full size they are within a few inches or so of being correct.  The following are the results.

 

NMM ID number            Type                  Height of mast on drawing                   Height of mast from Lees' multipliers and Establishment breadths for 1745  

J8287                           24 gun 6th rate         872 inches                                                 875 inches

J8283                           50 gun 4th rate         1089 inches                                              1092 inches

J8288                           80 gun 3rd rate         1279 inches                                              1280 inches

J8289                           90 gun 2nd rate        1316 inches                                              1315 inches

J8286                          100 gun first rate       1380 inches                                              1370 inches

 

I may be wrong to do so using such a small sampling, but I find that the lengths in Lees are based on the entire length of the mast.     

Hope this clarifies at least a little.  This at least gives one an argument to back up the mast height based on the formulas in Lees for this time period of 1745 to 1773.   Hopefully he was as accurate in the other time periods.   Maybe someone can look for additional contemporary drawings in other time frames and confirm or refute the other multipliers he uses as well.

Allan

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But David, we all want to know why!!!!   😀   This is a little difference in over all length but at quarter scale could be in the neighborhood of 1/4" and bothersome.  The main point though is that it is not up to the hounds as thought possible above.  That would be a huge difference.    

 

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Allan,

 

Thank you very much!

 

I thought about doing what you did, but I don't have enough information about individual English ship hull and mast dimensions to get any meaningful results.

 

I was pretty sure Lees was using what some authors call "measured length" from the foot to the top. But quite a few authors (and rules) use the hounded length, so I wasn't certain.

 

I am using Lees' rules for rigging to determine rope sizes. I figure that regardless of the type of ship and ship size the relationship of mast diameter to rope diameter/circumference was probably about the same for all ships. Schooners typically had smaller mast diameters than did full square rigged ships, but the mast diameter should still serve to determine rope sizes. Small boat rigging is another thing!

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Posted (edited)

Good Evening gentlemen;

 

Good work Allan; congratulations on a thorough working to find a definitive answer. Though it would seem that the length of the masthead was not a hard and fast matter, even as late as 1773. See extract below, taken from a contemporary letter book. This gives the Navy Board order to regularise mast lengths in accordance with various multiples. However, it is stated that this has been done because wide differences have been found. The ideal measurement was obviously not always achieved/known/complied with, for whatever reason.

 

Contemporary documents relating to the Royal Navy in the 17th & 18th centuries do not, unless my memory is completely failing me, ever talk of hounded length when describing the calculation of mast lengths; only of mast length. Which we can take to be, as Allan has demonstrated so well above, the overall length of all parts together. 

 

The NMM has a good number of careful scale drawings of contemporary masts from the last quarter of the 18th century, which give a lot of detail of the construction and appearance of a warship's masts.

 

There are also a multiplicity of contemporary documents, stretching as far back at least as the reign of Elizabeth I, which give mast and yard lengths for a great variety of vessels, by rate or by individual names. It is often possible to find the sizes for a desired ship amongst these. 

 

All the best,

 

Mark P

 

image.png.d4fd636907a7927c99200959b4e94d10.png

 

 

Edited by Mark P
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