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Arthur Goulart

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Everything posted by Arthur Goulart

  1. I'm happy to be able to help. Translating that was super interesting too so, it's a win win. 🙂 And, Waldemar, thanks a lot for the excerpt, it sure looks very helpful! I'll read it before I make more progress with my Wildmanden endeavour for sure. Appreciate it!
  2. It's for sure one cool riddle to interpret those old texts though! Ohhh I see. It adds up! I didn't know the Danish eventually smoothed it all out. Druxey, I don't think it's a matter of age related or even scanning issues for these specific Wildmanden/Hvide Ørne plans. The reason being is that the straight lines are very straight on them and all the perpendiculars are very close to perfect 90º. Drafting those curves precisely by hand and eye, however, isn't easy. What that would entail is applying a 9 number progression to a space of, at most, 3'2" ÷ 48 (which, I take it, is probably the scale the plans are on). After getting the correct proportions for said lenght, the draftsman would, most likely, draw provisory line from where the curve starts amidships parallel to the waterline, and use this line as reference to set, lets say, the wale curve. For that, he would measure the space from the beggining of the progression to the first division. Then, he would take the measured distance and apply it from the reference line up on the C frame (the first frame that has a perpendicular on the sheer plan fore of the midship frame), and so on, as many times as there are perpendiculars to the stem. Maybe he simplifies it, and he doesn't apply the respective heights on every perpendicular. In conclusion, there are many opportunities for small errors to be introduced. Thing is, I was about to write a whole segment on why if my progressions were wrong, I'd expect to see the error on the wales of Hvide Ørne, not on its sheer, then I'd explain why it isn't possible to give more inclination to the sheer's progression to get it right with the plans. But, before all that, I decided to take one good shower. *Eureka moment*. The explanation is simple. The sheer does not get a progression of its own. Instead, Turesen, at least for Hvide Ørne, did that entire process to get the curvature of the wales, but, instead of doing it all again for the the sheer, he simply copied the wales' curvature and rotated it two inches down, and there you have it: the sheer line. It matches perfectly. Let's zoom in on the problem area again: In blue, the previous solution; in red, the new finding. Notice how my line is slightly above the plan's line for the wales. Notice how that very same slight difference is now seen on the sheer with the red line; and notice how the blue line is not that slightly above the sheer. I think it's a hit. It has be said that the rotation solution isn't random either, the same is observed when drawing Hvide Ørne's forecastle and quarterdeck rails. Now I have to test out what that means to the aft sheer line, and how that finding can be applied to Wildmanden too. This all also goes to show how careful Turesen was with his drawings, the man knew consistency, that much can be said. -Arthur
  3. Trevor, this week I learned I don't even know my on portuguese language when translating Livro de Traças de Carpintaria for Waldemar 🤣 Makes perfect sense now, Waldemar! Thanks a lot for taking the time to figure it out and to explain it! That's interesting though, wouldn't they be already familiar with the Danish type fo wale from French ships? If the Boudriot monographs are to be believed, the french had the same blended wales as the Danish did since somewhat early on. That's not what the captured plans for Belle Poule, for instance, suggest (Belle Poule (1780) | Royal Museums Greenwich). But Boudriot's monograph do give Belle Poule blended wales: Fascinating stuff!
  4. Since the last post I made, I've been dwelling with the wale/deck/sheer curvatures. I'm convinced Turesen applied an angle to the progression used to draw them fore. Lets first get back to the G1228 60 gun ship scaled up from Fyen (1749) that I showed you last time. The previous post I explained how a 1,2,3,4... progression was used to define these curvatures aft: What I didn't show you, however, is that the plan presents a different triangle for setting the same curvatures fore: At first, I thought this was another 1,2,3,4... progression, thus not different from what is seen for the deck aft. But, it is not. You see, what its spacing suggests is that it results from an angled line applied to a 1,2,3,4... progression. To make what I mean clearer: That's how it looks when both the 1,2,3,4... progression (in blue) and the 50º progression (in red) are scaled to the lenght of the base of the fore triangle: (in green, where there are both blue and red points) This is not the same as is shown for the wales (barckholtets) aft, it's actually the opposite. The 50º angle gives the wales aft a more uniform incline, it makes them more akeen to a straight line, if you will; while the curves fore start off gentler and get steeper towards the stem. An exaggerated representation: As for the G1228 60 gun ship, it is possible that we have more of a 48º angle to the progression instead of a flat 50º one, but that specific plan was not neatly drawn at all, so, hard to know. The important thing to be noted here though is that despite, in practice, the difference between a deck drawn by a 1,2,3,4... at 60º (so, parallel to the base of the triangle) and one drawn by a 1,2,3,4... at 50º being very slight, for some reason, that differentiation in methods for the fore and aft parts was done. Grant it, that still is just one plan, it would be quite the bit of anecdotical evidence to be considered for Wildmanden. Well, it would be, if the same wasn't observed not only on Wildmanden's plans, but on Hvide Ørne's (1753), and on Fredericus Quintus's (1753) too. They all have a curves that get steeper towards the stem fore and straighter ones aft, as to suggest the same idea present on G1228 is present on these Turesen designs. So, I got to more testing on Hvide Ørne and Wildmanden, I tested all kinds of progressions, and two other methods too: projecting the a section of a circle onto the frames and getting the heights of the wale/deck/sheer at each frame that way (a method I've seen by english shipwrights), and drawing the curves by a circle that has it's center 90º above where the curve starts amidships. Those alternative techniques yielded no better results than what I got from triangular progressions. My unorganized progression tests: What I landed on for Hvide Ørne (1753) was a 1,3,5,7... 60º progression for all aft curves, starting off on the fore midship perpendicular; and, a 1,3,5,7... 50º progression for all fore curves, starting off, again, on the fore midship perpendicular: Some close ups of how it is looking. I'm quite happy with all the aft curves, and all the fore curves with the exception of the sheer, where some deviation that I feel like could be something that I'm still missing is seen: I tried applying the same progressions for Wildmanden, again, with satisfactory results for the aft. But a similar problem presents itself fore, but the other way around for Wildmanden. While my sheer line agrees with the drawing, the deck/gunports and wale curves show a slight deviation. The recurring issue in both drawings being that the sheer doesn't seem coherent with the other fore curves. On Wildmanden: I could fix Wildmanden's curves that aren't the sheer by using 1,2,3,4... 50º instead of 1,3,5,7.... 50º, but if I were to apply the same to the sheer, it then would have a deviation from the plans. For Hvide Ørne (1753), however, the 1,3,5,7.... 50º is the best solution I found for all curves. It might be just a matter of imprecision of the hand drawn plans, I'm open to suggestions though. If I find something better, I'll let you know, if not, we'll move on to explaining the stem/sternpost and the location of the quarter frames and transom diagonal. And, by the way, Hvide Ørne has some pretty interesting differences for how it's body plan is done, should I make the topic a two in one package by exploring both Wildmanden's and Hvide Ørne's lines? Cheers! Arthur.
  5. I missed answering your post previously, Martes. Apologies. But yeah, it makes perfect sense to that the paintings shouldn't really be trusted in the matter. And that 1807 passage is gold! I mean, I could never imagine that is the advantage behind one type of wale over another. I wonder what's the plus of not having the wales blended into the planking. Maybe easier construction? As the thinner planks would be easier to bend.
  6. That is very neat and clever, Waldemar! Those were the lines I couldn't wrap my head around. You've arrived at an explanation that produces a very spot on result and that makes sense. The one thing I didn't understand is how you came up with the position of the thick auxiliary construction lines. Could you elucidate it? Thanks a lot!!
  7. Ok, ok, ok The first post has stirred the pot much more than I would've imagined. That's awesome! Happy to see so many of you guys engajed on this project. The context given by @TJM (thanks for it by the way!) is a perfect introduction for the next part of the reconstruction, as will be clear. Let's get to it: GUNDECK, SHEER LINE AND WALES As already noted, Wildmanden, was designed leveled to the waterline rather than the base of the keel. That's a method that is never seen on English plans of the period, that isn't the most frequent with French ones either, but that was common in Nordic practice. What it means for this chapter of the Wildmanden reconstruction is that all measurements make most sense when taken not from the rabbet and up the perpendicular, but rather from the waterline, or, better yet, from the line that is paralel to the waterline that starts on the lowest edge of the keel aft, henceforth I will be calling baseline. From the baseline up the perpendiculars, the heights for the ends of the curves that form the lower and upper limits of the gunports, the wales, the sheer are the rounder, and I mean, so neatly round it can't be a coincidence, and I'm convinced I got the heights chosen by Turesen right. Let's see: The lower side of the gundeck is offset 1'7" relative to the lower limit of the gunports. The upper and lower gunport limits, as well as the deck, ends at the same height aft relative to the baseline as fore. The sheer line drops 1'6" in height amidships, then rises 3'0" aft. The upper edge of the wales ends aft 2'0" above the lower side of the gundeck. The freeboard amidship is given by Turesen as 5'6". I think that shows the point, except for the lower side of the gundeck (which makes sense), all dimensions can be explained with a 0.5 feet precision. Interestingly, a proportion can also be observed when comparing Wildmanden to the unbuilt A1246c brig. On both cases the deck/gunports line rise fore and aft 1/3rd of the freeboard. Now, to the more interesting part of today's post, how these curves are formed. The shipbuilding manuals of the period I've read so far really overlook the description of these curves. Not only the shipbuilding manuals, I was overlooking the lines myself, I had a sort of working solution, but without a basis in literature or something else for it. That's when I stumbled upon a specific plan, G1228 (which, by the way, lovely looking ship, I'd love to reconstruct it in the future too). That plan is for 60 gun ships built based on Fyen (1749), that TJM taught us about. On G1228, the method for forming the deck and sheer lines is represented: The plan, is unsigned and from 1758, by then Turesen had died. However, the plan also informs that the Storman, the Island, and the Seyeren were built to its lines, ships that went through Turesen's hands. The previous plans for the type available on the archives are all from 1750, before any of the three ships was finished (and maybe even started, I'd have to check). The older plans show a different deck layout, and don't demonstrate its forming. The fact is, even if Turesen wasn't responsible for showcasing this progression based method for drawing the decks, he certainly was familiar with it, and I think, that is the practice behind Wildmanden's lines. It works quite simply: a progression is made by setting whatever length, let's say 1 inch; from the end of this first length, 2 more inches are set off; then 3, and so forth. As many lenghts are set as there are perpendiculars from the master frame to the stem or sternpost. Connect it all to the apex of an equilateral triangle, as seen above. That forms a ratio that is applied to the amount the deck, sheer, wales rise. In Wildmanden's case, for example, the deck rises 22 inches: 15'7" is its height from the baseline amidships, and 17'5" on both extremes. That ratio determines how much the curve rises on each frame. I hope that makes sense to everybody reading. But, the only way to know if that was indeed what was done on our ship, is of course, to try it out. And that I did, but not only on Wildmanden, but more importantly, on the unbuilt A1246c brig. Any variation of the method I tried was kinda good enough for Wildmanden, since the curves on it don't rise all that much when in relation to the frigate's lenght. On A1246c, on the other hand, the sheer skyrockets (technical term 🤣) up aft. So, I tried using a 1,3,5,7... progression, I tried applying the sheer rise to the equilateral triangle on different angles (as is seen for the sheer line of the 60 gunners above), I tested different progressions fore and aft, I tested the progressions on the wales, and so on. The conclusion is that the 1,2,3,4 explained well enough, actually, more often than not, explained the best, all the different curves. 1,2,3,4 progression applied on A1246c: Pretty good, right? There is that principle where the simplest explanation is the most likely, I think it applies well here. No need to go extra with it when 1,2,3,4 is enough. That's how it looks on Wildmanden: There is one spot where my curves don't line up so neatly though, the fore part of the sheer line and its parallel rails: I could have the sheer's curvature align better with the plans by changing my method up, but that feels criminal. I mean, what that would imply is that Turesen used one same method for the wales, for the deck, for the gunports, for the aft sheer, but for whatever reason he decided to mix it up to get a very slightly different result on the fore sheer. Also, the upper forecastle rail seems like it should be half an inch narrower. Which, also, I find unreasonable. The correspondent quarterdeck rail is 6 inches wide, what's the point of making the forecastle half an inch narrower? What seems to be at play here are some more sloppily drawn curves rather than an intentional variation of technique. What do you guys think? Now, time to translate the Livro de Traças de Carpintaria for Waldemar! 😁 Cheers!
  8. Correct! On A1226e you can see it separately. The aftside should have a quarter frame too, but it's too close to one of the actual frames, hence why I think it was not represented.
  9. Yes, please, @TJM! I found it pretty difficult to find information about Danish shipbuilding online, and well, it doesn't help that I don't speak Danish, so that'd be awesome. I do! But thanks a lot, regardless! I might make contact with the people who run the archives though to see if I can get hold of some of the Wildmanden drawings that aren't available on the website. I suspect some alterations were made to the sheer plan after A1226c (the plan I posted above) were made, as the sheer line appears taller aft and the keel and stem look thicker on the later interior arrangment plan (A1226b) Do you think it could be a difference between warship and merchant ship practice? And so painters would eventually get it wrong? The models seem to agree with what we see on the plans. Take a look at this illustration, the ships have their wales outlined with black lines, but the wales themselves are wooden in color: The image deviates from the gradually diminishing wales we see on the plans, yet, it suggests that what is seen on other illustrations isn't a matter of how the wales were painted. Eventually 😁. But I just graduated, and I'm studying to get a well paying job, so I wanna get my own money sorted before I get to wood and sawdust. I wanna make her real nice, that takes money though. Meanwhile, I have a terribly designed Bluenose kit that I'm slowly messing with. Waldemar, that's why it will be awesome to have you following along this reconstruction! Parabolic variant of the Northern design? I have no idea how that method works, would love to learn about it though. However, Turesen gives instructions for the midship frame on A1226e it is made by only two arcs below the breadthline, a smaller one tangent to the breadth, and a larger one, that starts tangent to the smaller one and intersects the end of the floor timber. Above the breadth, two more arcs, again, a smaller one tangent to the breadth, and a larger one, tangent to the smaller one that ends on a point at the sheer's height that has 4/5th of the midship's frame half breadth. All radii are some proportion of the breadth. That's what Turesen describes: That leaves the hollowing curve unexplained, hence the other topic I started. I haven't yet looked into what you pointed me towards though, the Boudriot's articles. The reduction of the frames is done by the french equilateral triangle method, aided by a Luff frame, which I think I've seen in english as a quarter lenght frame, something of the sort. It's an intermediary frame (in red on the figure above) that defines the angle by which the ribbands are applied on the equilateral triangle. I'm using Rhino, Waldemar 😁 I tried blender out, it was no good for this purpose. You sure may! It's portuguese. I'm an across the ponder, from Brazil. If you need some help with those 16th century portuguese manuals, I'm more than happy to help out! Matthias, thank you very much! Those are great. They confirm my suspicion about where the wale line is on the model. There are some very weird wide planks on it though. Do you guys think that could be a correct representation of how the real ship was planked? Surely not, right? That is awesome to know!!
  10. There are some outstanding contemporary models for sure, not surprisingly, when you consider some of them were made for the royal, some were made on comission by important people, some were prized gifts. @Beckmann a couple days ago linked me to an article of his that showcase some of the finest Danish models: https://www.arbeitskreis-historischer-schiffbau.de/mitglieder/ontour/schiffsmodelle-in-daenischen-museen/ .I take it you're probably already familiar with the models on RMG's website, besides that, I'd suggest you check out the Roger's Collection, the collection of the Musée National de la Marine, the Museo Naval de Madrid has a lot of their models on their instagram page, be aware though, that is one rabbit hole that you can't get out of 🤣. Happy to have you here @druxey! You touched on a good point there, the sheer plan is deceiving with regards to the wales. The 'midship section plan' (or however I should call it lol) suggests the ship wasn't built with two standing out wale strakes, rather, a more french approach was taken. The space between the lower and uper wale strakes is filled, and the planking gradually diminishes from the lower strake towards the rabbet: So, what I'm making of the model is that the wale line is actually here: But then again, very hard to tell. Hopefully some better photos can clarify it in the future.
  11. @Y.T., sort of. I don't really know of any examples where the wood was tinted per se, but shellac or plant oils were commonly used to finish these old models, and those have some color to them. The old look comes from oxidation, grime, etc., of the wood and finish.
  12. This week I went through a few of Waldemar's topics, and got inspired to show my progress on "reverse engeneering" the lines of Wildmanden, and to eventually get to a full 3D model of her. While I'm far from being as knowledgeable as he is in all matters ship drafting, I believe I can go a long way with good sources, the input from the great people on MSW, and a fair amount of trail and error. In that sense, I insist that you guys point out where I've got something wrong, even if you're not sure of it yourself, we might learn something by looking into it. My limitted experience trying to redraw plans was with an english 23ft launch. I've gone further along with it than what I have posted, but my law school's final paper got in the way of the project, and the drafting attempt got me to realise that I wouldn't be able to reach my end goal to a standart that would satisfy me. You see, the main reason I actually picked that specific launch to reconstruct was because that's the size of launch Inconstant (1783) would've carried. At the time, I meant to eventually reconstruct the frigate, but through my trials with the 23ft boat I learned that redrawing her plans would require more guesstimates about various dimensions and designing techniques than I'd be happy with. That got me back to the ship choosing board, until I eventually landed on Wildmanden, and other A. Turesen (her designer) boats. Why Wildmanden? To begin with, I find her lines very pretty: she's got a good amount of sternpost rake, unlike most of the french earlier "true frigate" designs; it isn't too long relative to its breadth nor does it have extreme tumblehome, which, again, are recurring themes with french designs; unlike it's english counterparts, it's body looks much sleeker, the swan sloops, for instance, feel top heavy to me; the distance between the main rail of the beakhead and the upper cheek rail on english sloops and frigates is often too narrow, and the main rail leaves the ship's hull too low. Most importantly though, the many Wildmanden plans present an abundance of dimensions and illustrate and explain many drafting techniques that are paramount to an accurate reconstruction. Not only Wildmanden, Turesen has left plentiful drawings, equally detailed, and as the Danish Archives make those available in high resolution, they make for excellent comparative material. Specially relevant for this reconstruction are those for the Hvide Ørne (1753), another really beautiful frigate in her own right; A1246c, a brig design that was never built; and, surprisingly, the plans for Fredericus Quintus (1753), a full on first rate ship of the line, that, in spite of being of a different league of ship, was drawn by many of the same rules observed on the aforementioned designs. Above, the plans for Wildmanden. Although a fregatten by Danish denomination, her dimensions are more akeen to a british sloop of war, or a french corvette. The Krigsmuseet holds a contemporary model of Wildmanden, unfortunetely, I could only find two photos of it. If somebody happens to have some more angles of the model or otherwise happens to visit the museum and would be willing to snap me a couple more images, it'd be much appreciated! (credit: modellmarine.de) The goal here, at first, is to showcase and discuss the methods for forming the different lines of the ship, together with findings in proportions. I hope to have you along. The next post, we'll begin by adressing wales, gundeck, and sheer line. -Arthur
  13. Matthias, thanks a lot for the link, those are some great references. I probably will be bothering you more down the line for some extra photos 😁. I wonder how much of Fyen's rig was kept original. Also, thanks for the feedback on the book. And, @TJM thank you for pointing me towards the guns and the cadets' book. Good thing too that going through the archives is quite fun, a bit of a treasure hunt. Cheers, guys!
  14. Matthias, This build is coming along great! Awesome atrention to detail and I love the subject! I've read through your topic, and some questions in regards to sources came to mind. You mentioned 'Danske Orlogsskibe 1690-1860', how good is the book?? Is it aimed on the general public, or does it go in depth about specific danish shipbuilding practices? Does it present sources outside what is available on the Danish Archives or otherwise online? Are there other titles you'd point to that discuss danish practices of the period? You've presented some great photos of the Tre Kroner model and others, some taken by @TJM. I am having a hard time finding Krigsmuseet's model's references online, would you guys mind sharing some more of those? Maybe on the gallery of contemporary models of MSW? I'm messing with some Danish ships myself, specially Wildmanden, that I'm the furthest along with, and taking a look at those models would really help clarify some details the plans often omit, such as anchor linings, oar ports, fenders, rails, cheek fillers, etc. With regard to the artillery, how are you finding those drawings? What I mean is, while there are listings referencing specific ships and their respective drawings on the Danish archives, I'm not aware of the same thing for guns and other various fittings. To find those, I usually just look through a bunch of plans until I eventually find something useful and then download it. Am I being dumb? 😆. You also mentioned instruction manuals for cadets and the shipyard, could you link me those? Thanks a lot, Matthias! Looking forward for the continuation of this incredible build!
  15. Yeah... The abyss has stared back at me, nothing I can do about it now 😆. I can already see some ways the comparison will be useful in the upcoming steps, I'll probably be able to improve, or be reassured of my design for the boat's rake, sternpost and rudder. Having those four other plans is quite the unique opportunity to understand what was the designer's process. And on the topic of Marmaduke's Naval Architecture, I'm actually kinda surprised I had no idea that book even existed. I had a quick look through it, it seems to be just the thing for this project, much more complete than Steel's when it comes to whole moulding, and that plate 1 find was a great one, @iMustBeCrazy! And btw, do any of you have a pdf for The Shipbuilder's Repository? I have looked everywhere for that and found nothing but crazy expensive physical books.
  16. It's actually 3 months of free trial, Michael. My biggest struggle was more understanding all things shipbuilding related than the program itself 🙃
  17. Following @Waldemar's suggestion, I took to measuring. Not only I looked for proportions on our 23ft launch, but I browsed around RMG's website and found a couple more launch plans dated 25th of April 1785 by Adam Hayes, namely ZAZ7353 (21ft), ZAZ7352 (22ft), ZAZ7351 (26ft), and ZAZ7348 (30ft). I figured, if there is some proportional rule to the construction of these boats, comparing the plans would reveal it. So, I did the unthinkable, created a spreadsheet. Here are the results: I hope the measurement descriptions make sense. Everything is in inches. The "/lenght" columns refer to the previous measurement divided by the lenght of the boat. I was also curious if this exercise could help me with the question for the height at which the lower points for forming the sternpost and the rudder are set, if at the height of the base-line, or at the height of the keel's base. An example will make it more clear, the sternpost's outer edge is a line that passes through the aftmost edge of the sheer strake, and through a second point down below, that is either at the height of the base-line, or at the height of the keel's base, I don't know which. Although the spreadsheet gives pretty damn similar proportions between the different boats at both the base-line's and keel's base heights, I think those at the base-line's height make more sense, that is 1/30 of the lenght = sternpost width, and 6/100 of the lenght = rudder width, at least for the three longest boats, . What do you guys make of it? Do you see any other proportions that also make sense? -Arthur
  18. Guys, thank you a lot for the posts. This little into the project, I already got some valuable insights! Sheeesh, those are really inconsistent gaps. Can you see some logic behind them? I like the way that sounds, Waldemar! But, how do I know which proportions to look for? I mean, any division between two lenghts will give me a proportion, how would I know what is correct? I've had a look through The Elements and Practice, in the 'GENERAL OBSERVATIONS ON THE PROPORTIONAL DIMENSIONS' chapter, and I couldn't quite make out something aplicable. Maybe I can get somewhere by comparing different boat plans? Got it! Ohhh I will not indeed, Vaddoc! And drafting in CAD is quite addicting. Hours will go by and I won't notice it. I definetely will spend some time taking a good look at your longboat!!
  19. By no means! You guys just gave me something new to fiddle with 🤣. I went with Rhino because I thought it was the best out there for our purposes, but nop. I'm sure glad I'm still just using a free trial, because Rhino is quite expensive. A free and better alternative? Count me in. By the way, those boats look awesome.
  20. A little disclaimer at first, when measuring distances off of the plans, I'm looking for the most logical values. That means, I don't think that when setting a line someone would go with the "7/64th of an inch" option, specially because, keep in mind, these plans were drawn at scale. When two possible values get close to the lenght of a given line, I'm picking the rounder one. As a general rule for this project, 1/2 is as far as I am going when dividing inches, unless there is good reason to think a more specific value is correct. Onto the first steps. The first view of the ship to be drawn is the sheer plan, that is, the side view. We start off with the base-line, which coincides with the upper edge of the rabbet of the keel, on ships, it ends perpendicular to the fore and aftmost edges of the lower deck. On boats, however, it stretches from the aftmost edge of the sheer strake to the foremost edge of the stem, and represents the lenght of the vessel, so, in our specific case, 23ft. From both ends of the lines, two perpendiculars are drawn, these are important references for other lines to be set. Next up, to set the midship perpendicular, which not always is precisely amidships. Here it is 10'10-1/2" from the foremost perpendicular. From it, the other, evenly spaced, perpendiculars are drawn. For our launch, they are a weird 1'2-3/8" of one another. I came up with that for two reasons: that value aligns much better with the H and 9 perpendiculars (the outmost ones) of the original plans than a 1'2-1/2" spacing; and, because the plans for a 30ft launch (ZAZ7348), by the same author and date, show, again, the same 3/8" spacing, 1'3-3/8", in this latter case. I wonder the reason behind the odd choice. The stem is mostly formed by arcs centered 3'4" up from the base-line and 3'10" aft from the foremost perpendicular. That point is reassured by its correspondence with a little dark spot on the original plans, that I assume is where the point of the draftsman's compass laid. From it, with a 3'5" radius the outer edge of the rabbet is set; with a 3'4" radius, the inner edge of the rabbet; and, 3'2-1/2", the inner edge of the stem. These latter two arcs, however, are fictional, they do not correspond with how the finished boat might've looked in the past, and will not stay this way on the finished 3D model. More on that later, they are good enough for now. To the keel and outer edge of the stem. I previously thought that the base of the keel was a little too wide on the sheer plan: the body plan shows a narrower version (more like 6" from the base-line instead of the 6-1/2" shown in the sheer view), and that means that a 3'10" radius from the same center already discussed would intersect perfectly with both the foremost perpendicular and the bottom of the 6" keel. But, the neat result was a bit too off in relation to the plans to my likeing. One particular detail came to my attention, 3'3" from the foremost perpendicular there is a sharp edge, that suggests a not too perfect junction between the stem's outer edge and the keel's base, a bug or a feature? I came to the conclusion that it is, indeed, a feature. Many plans and models show such an edge (the Medway longboat for example), and notably, that 30ft launch (ZAZ7348) by the same author and date also features that edge, and there it looks even more intentional. So, I now have adopted a 6-1/2" keel width, the outer edge of the stem is made by an arc that is centered on the same height as the center of the other radii that form the stem - so they end at the same height too -, but that intersects the base of the keel 3'3" aft off the foremost perpendicular. That solution is much more in line with the plans. - Arthur
  21. Loracs, I'm using Rhinoceros, I found it to be rather intuitive, messing around with it a little and some quick google searchs have gone a long way for me. I have not tried something different, so I can't compare. Rhino seems to be what most folks use here too. And, part of the reason I started this topic is that I haven't found one that adresses my questions regarding redrawing plans, so I hope to crowd source some knowledge through here.
  22. So, I wanted a not too complicated to learn both 3D modelling and ship construction. I decided to go with a ship's boat, because you can't get much simpler than that for a first scratch project, and because the result might come in handy in the future for ships that, well, will be fitted with boats. Imagine the designer behind the plans had access to a CAD program, that is what I'm aiming to achieve. Thus, I'm looking at understanding how ship's lines were formed, so I can reconstruct this little launch from principle, not from merely tracing all the plan's lines. With that, I hope to get a more accurate model to the original designer's vision, by mitigating the limitations of the hand drawings and measurements of the time, of the 200+ years of wear the plans have been through, and of the distortion the scanning process might've added on top of it all. On this topic, I'll be registering my progress, in a step by step manner. I insist that you guys point out where I've got something wrong, even if you're not sure of it yourself, we might learn something by looking into it! I'm expecting to make plenty mistakes, and the purpose to pick something simple is that I can start it all over again without pulling too many of my hairs off. So far, my main reference has been The Elements and Practices of Naval Architecture, from '§ 2. OF THE CONSTRUCTION OF THE SHEER DRAUGHT OF THE EIGHTY GUN SHIP, FROM THE GIVEN DIMENSIONS' (p. 242) and onwards. Steel's book is aimed mostly at full on ships, but many instructions are aplicable to our purposes, many require a fair deal of interpretation - he is not the most clear and didactic, which is not helped by my still limited knowledge of ship building vocabulary, and by english not being my first language. Why this 23ft launch was picked, specifically? I tried a couple different boats out, I made some sense of this one the faster. The stem's radii and those of the midship frame are really important dimensions that I struggled with on other plans, but that I fairly confidently figured out for this launch. My take is that ship's boats were neglected subjects in their time, at least from a more technical stand point, and that today they likewise get less attention when compared to the more complex and exciting subjects, hopefully this will be a more thorough and complete reconstruction. The next post, I'll take you back to the beggining of the model's construction, but, for now, I'll leave you with how the model is looking present-day: - Arthur
  23. There is a very notorious reference that you might have forgotten about: Grant it, she was restored a couple of times, but Victory is some 15 years older than Perseus and, still, show no scarphs.
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