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JohnMGray

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  1. I use Rhino for boat/ship design, and Solidworks for parametric CAD so I'm not too familiar with AutoCAD. The link I previously showed has some ACAD tutorials on it. Regardless, you want to use a NURBS curve, or whatever ACAD has for an equivalent. Then you draw a single curve (with multiple bends) through the whole station (top to keel) (or along a curved waterline or diagonal) using control points, and then use the point handles to bend the curve to fair it for a better fit. You can do this two ways. Use my above method to get all of the waterline/station intersection points for a single station (or waterline or diagonal), then connect the points with the curve. Or, freehand the curve by clicking at points logically located along the station line (or waterline or diagonal) such as as maximum/minimum concave/convex points. Don't make a single station line consist of multiple sections/curves. It should be one curve/line with multiple control points. Also, I find that too many points is more of a problem than not enough, although you can add or remove points easily. Once you've done a couple of them you'll see what's best. I should also mention that the only time I use multiple segments is if drafting the plans from scratch. Then you draw the arcs in accordance with standard methods, overlapping the ends, and delete the excess parts beyond where the arcs intersect. But you'll still find yourself combining the segments and using control point handles to fair them. Deane's book is a good one. I have my copy in front of me right now for research I've been doing. Steel's "Shipwright's Vade-Mecum" is also good. If you don't have a copy of the folios, or access to them, you can order digital copies of them from the Bodleian Library at Oxford University.
  2. One drafting trick I learned from school (in the 70s on paper and vellum) was as follows. If I draw a horizontal line from the intersection of station 38 and waterline 4'6" on the shear plan (point A) to the same intersection on the body plan (point B), then draw a vertical perpendicular line from the body plan (point B ) to the intersection of a 45 degree line from the centerlines of the body and half breadth plans (point C), then a horizontal line from point C to station 38 of the half breadth plan (point D), it should intersect with the waterline 4'6" on the half breadth plan, which will be the same as back at point A. All lines are 90 degrees from each other. This holds true for every intersection on the plans. So if the shear and half breadth plans are good then you can easily recreate the body plan stations, or create the half breadth plan from the shear and body plans. If the 3 plans don't line up as shown below then just digitally cut them apart and make them line up.
  3. If you haven't already seen it, download "Drafting Ship Plans in CAD" by Wayne Kempson, from "http://modelshipworldforum.com/ship-model-plans-and-research.php". As far as warped plans go if they are really bad you can make a template overlay using baselines, waterlines, centerlines, station lines, etc. Then use the overlay set to translucent to unwarp the plans in any decent photo editor (e.g. Photoshop).
  4. I used Richard Barker's title when he published it in the Mariner's Mirror in 1994. It's also believed to be a copy of at least one or two earlier works so it's difficult to determine an original date for the information. It's similar to "A Treatise on Shipbuilding, c. 1620" published by the Society for Nautical Research in 1958 by Dr. RC Anderson which also appears to be a copy of an earlier work, and which happens to be just one part of "MS 9; Orders and Instructions of the Duke of York, 1660" from the Admiralty Library. Both of them show an influence by Mathew Baker "Fragments of Ancient English Shipwrightry", who's own works were added to after his death. At the moment I'm working on a spreadsheet comparing the descriptions, methods and calculations of each of them, along with Deane's. I may also add William Baker's calculations and measurements of his new Mayflower as he studied the early works for his design. [edit] Also consider that parts of the Newton manuscript are almost word for word copies of the Scott manuscript (old RINA 798 which has been sold to a private collector), and that the other parts, although not word for word, closely agree. John Coates tentatively dated the Scott manuscript to 1590-1605. I wouldn't be surprised if both the "Newton" original sources (besides the Scott manuscript) and the "MS 9" original source also date from that time period.
  5. Thanks Mark, I've seen those. I've been doing a study and comparison of late 16th century through mid 19th century British and American ship design and building. I've been going through period manuscripts and monographs including sources from the likes of Baker (Fragments of Ancient English Shipwrightry), MSS Add. 4005 Part 12 (A Manuscript on Shipbuilding, Circa 1600, Copied by Newton), Bushnell, Sutherland, Deane, Murray, and Steel, just to name a few. I'm starting to translate some of their works into CAD (Rhino 6). As I go along I've been finding other modern papers on early wooden ship design and building, such as White, and have been just checking their interpretation and presentation. As I translate the early works to CAD I may end up documenting step by step instructions and releasing them to enthusiasts. If so, I hope to include the rules and methods of each early shipwright / era so people will understand both how and why. From there it's not too difficult (just time consuming) to translate the 2D plans to 3d with parametric CAD, and to fully frame and plank a ship. Then they'll have everything they need to build a wooden model if they choose. John
  6. Thanks Derek. I'll keep checking but the most likely source from what I've found so far is the combined volumes from UK booksellers. Unfortunately I'll have to wait until the virus bans are lifted to be able to get them shipped to the USA. I'm still waiting on a special publication from the Society for Nautical Research I ordered from Switzerland. It arrived in this country on April 9th and I haven't received it yet, and I'm on the east coast.
  7. Hi everyone, I realize this is a few years old, but would anyone still have a copy of parts 5 & 6 of David White's "Understanding Ships Drafts" from Model ShipWright Magazine? I really wish they would republish the old ones, maybe as a digital collection. Someone also mentioned that David White wrote a series of articles about shipbuilding but I can't find anything about them. Thanks, John Gray
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