I’m watching Fred. He’s got some crazy moves.
On second thought Paul I think I’ll move a couple of seats over.Renowned pole dancer...
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Sorry Fred. I'll go back to my seat now and be quiet.
Forgive me if this is out of line, but I wonder if you've matched the actual half frames to the drawings in the best way possible. There certainly may be (probably are) errors due to manufacturing and shrinkage, but I don't think it's as large as your drawing represents. It seems to me that the overall height and width are the most important factors, in getting a representative hull shape, and while you've matched the width fairly well (using the inner edge of the frame), the top is way off, as you say. And it appears that the half frame width (thickness, in the above view) at the top is somewhat wider than that on the drawing as well. At the very high aspect ratio of width to height, a small width change results in a large height change.When assembling each frame set, I discovered that the half-frames are shorter (by up to 1/8”, 4 inches in scale) than the drawings, and almost all differ slightly in curvature from the plans (flatter-floored). This looks like the result of some shrinkage of the wood across the grain after laser cutting, and will result in a vessel that is slightly lower at the rail and flatter in the bottom than the drawings, unless one wants to bin the laser-cut frames and scratch build new ones. I am not that ambitious, and the error at least seems to be consistent, so I will live with it.
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Hi Signet, I understand what you mean, and I investigated this when I was making up the frames. What I discovered was that I could either match the width of the drawing or the height from keel to rail, but not both. Since the more vertical frames at the bow are less affected by shrinkage, due to grain direction, I looked at those first. They are clearly shorter than the drawing shows, about the same amount, so I chose to match the width of the frame and live with the slightly shorter height. I also discovered that by matching width, I got a better fit in overall shape. This may suggest that some of the problem is not shrinkage, but a basic discrepancy between the drawings and the laser cut parts.Forgive me if this is out of line, but I wonder if you've matched the actual half frames to the drawings in the best way possible. There certainly may be (probably are) errors due to manufacturing and shrinkage, but I don't think it's as large as your drawing represents. It seems to me that the overall height and width are the most important factors, in getting a representative hull shape, and while you've matched the width fairly well (using the inner edge of the frame), the top is way off, as you say. And it appears that the half frame width (thickness, in the above view) at the top is somewhat wider than that on the drawing as well. At the very high aspect ratio of width to height, a small width change results in a large height change.
I copied this photo into my paint program, and made a layer of the actual half frame outline only in red, and rotated it (about 1.77 degrees) to where I feel it matches the drawing better. Yes, it's slightly narrower at the top, at least on the inside (a bit less so on the outside), but I think an overall much better representation of the hull shape:
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The moved/rotated frame is shown in red, and as you can see, the inner contour is now quite close (no outer contour was shown for me to compare), with just a small change in the width at the top. I think this would give more success in duplicating the hull shape as closely as possible. If you agree, it would still be possible to make such a change (which would apply to all the half frames). If not, then carry on, I'm sure it will be a lovely model regardless. Good luck!
BTW, good work on the jig with help from your engineer son. As an engineer son myself, I've never heard of "yak shaving", but back in my generation I'm sure we called it something different. (Just researched it: The term "yak shaving" was coined in the early 90s after a 1991 episode of The Ren and Stimpy Show. As I graduated in 1965, I would be blissfully ignorant of the term. )
FredHi Signet, I understand what you mean, and I investigated this when I was making up the frames. What I discovered was that I could either match the width of the drawing or the height from keel to rail, but not both. Since the more vertical frames at the bow are less affected by shrinkage, due to grain direction, I looked at those first. They are clearly shorter than the drawing shows, about the same amount, so I chose to match the width of the frame and live with the slightly shorter height. I also discovered that by matching width, I got a better fit in overall shape. This may suggest that some of the problem is not shrinkage, but a basic discrepancy between the drawings and the laser cut parts.
The image I provided has a fair degree of parallax, so appears to exagerate the effect. When I took the image, I had aligned the outer edge of the frame as closely as possible to the outer edge drawn on the plan over as much of the length as possible. The closest fit was found when matching the overall width. If I rotated as you suggest, I could match the height, but would then not only get a narrower frame but the bilge curvature would end up out of line, and would not fair over the length as well.
Fred
The frame illustrated has the largest error, for most of the other frames the discrepancy in curvature is much less, especially on the inboard face.
Hej Maarten,Hi Fred,
I love to see that you and also Ab Hoving who are proffesionally involved in the things we love to do as a hobby are still involved in model building as a hobby yourselves.
Especially in willing to help others, for us that is of great help, as I experienced myself with the help of Ab in recreating a possible shape of the Ghost ship which will be my next project.
Looking forward to the rest of your build of this interesting small model.
Looking also forward to your experiences onboard Kalmar Nickel, we are all eager to learn and ofcourse share some jokes from time to time.
Hej Don,Fred
I was a draftsman a long time ago and we would have issues with paper expanding with humidity. It was the cheap blue ray paper and it was when we scaled from the copied drawings. Just throwing that out there but it sounds like you are working through the issue.
Carry on !
Don
That is true, while a different alignment may have worked on the frame illustrated, if the much more vertical frames also had the height difference, then that is a completely different case. I'm sure with so many parts affected, you took all into account and made the best decision for the model in general. If the entire assembled hull frame system is still 1/8" or so short, it may also be possible to add a 1/8" square stripwood longitudinally to bring the top to the correct height. But I'm sure you've already thought of that or have another mod in mind, or find that none is really required.The frame illustrated has the largest error, for most of the other frames the discrepancy in curvature is much less, especially on the inboard face.
Hej Fred,Hej Maarten,
If you have any questions about the Ghost Ship (I assume you mean the 1660s Dutch fluyt sunk in the middle of the Baltic), I am also happy to help. I was one of the lead archaeologists on that project. You might also contact Niklas Eriksson, who has been working on a reconstructed hull shape for the vessel.
Here at Kalmar Nyckel I am part of the engineering team. We are replumbing the engine room, overhauling and optimizing the bilge and fire pump systems, as well as changing a propeller shaft. Most of the drydock crew are busy on the outside of the ship, scraping and painting as well as renewing caulking below the waterline. We had a half-day off yesterday (because of the Labor Day holiday) so some of us went sailing around in the Mystic River in one of the Seaport's small boats, a Wood's Hole catboat with a sprit rig. A lovely afternoon.
Nyckel will go back in the water next week, after I fly off to a conference in Halifax, Nova Scotia.
Fred