Back for MoreHi, everyone (or, anyone?) Some time ago I began a thread here about creating a 1980s USS Iowa in 1/120 scale (7'-4.7" long) as part of a railroad scene at Naval Weapons Station Earle (New Jersey). I got sidetracked. I'd like to give it another go and hope that I'll get some great suggestions as I did last time.
I would say that I'm starting from scratch, but I'm not in that I learned a few things the first time around. One thing is that I'm going to ditch Fusion 360 software for another 3D program (I create line drawings in 2D before moving them to 3D). I draw the CAD models in 1:1 scale and will convert to model scale later.
I'm planning to use my tabletop CNC machines - mill and lathe - to cut almost every item needed to make the model. Natch, I'm beginning with the creation of the Hull. I want to describe and illustrate the steps along the way, maybe that approach will be helpful to some others. At the same time, a detailed approach might allow veteran modelers here to yell at me when I go wrong.
-Brian Chapman / Cedar Rapids, Iowa USA
HullStep 1I'm using the Body Plan (Station Lines) found in Paul Stillwell's book, 'Battleship New Jersey', pg. 295.
Attachment:
1 - Station Lines.jpg [ 116.85 KiB | Viewed 2336 times ]
I scanned the drawing into Photoshop, which allowed me to size independently horizontally and vertically to account for paper stretching during printing. Also, I corrected for angle of rotation so that the baseline is zero degrees. With adjustments made, the Fore, Aft and Midship deck heights were on the mark, as was the Hull width.
The deck heights, as well as other key dimensions, are found on the General Dimensions chart included in the Booklet of Plans for the several Iowa Class ships retrievable online.
Step2Once the Deck heights and Hull width were established in Step 1, I added the horizontal Waterlines (red) every four feet from bottom to top by using the software's Offset Tool for accuracy - the printed drawing's Waterline 48-inch separations vary, noticeable in the drawing below.
The Body Plan's dotted line indicates the height of the main deck, and the dotted line is what I used to create the deck heights above. The bottom Green line (below), using the software's Spline tool, is the Main Deck tracing, the top Green line is the height of the Side Plates that extend above the Main Deck. I settled on a 7-inch height for the Side Plate extension above the Main Deck - this doesn't include the 2-1/2 inch round that sits atop (or partly buried into) the 7-inch extension.
Attachment:
2 - Station Lines.jpg [ 41.4 KiB | Viewed 2336 times ]
Step 3Again, using the software's Spline Tool, I traced the drawings Station Lines (Green), sparingly using Control Points by snapping to the center of Station Lines where they crossed the accurate Red Waterlines. On a few of the sharper curves, I did click on intermediary spots between the Red Waterlines to create the correct curves.
At the far edges of the Beam Width, the drawing's (mostly) vertical lines amidship blurred together, so I did have to estimate distance ratios in that area. I'll see how that works when I join Station Lines with a skin in 3D using the Loft Tool. I think it'll work well.
Question 1: Station Lines 20 through 30 are not shown on the drawing below. Might this be because the Hull in these locations is full width and 90 degrees vertical?
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3 - Station Lines.jpg [ 127.61 KiB | Viewed 2336 times ]
Step 4I'm working with each Station Line separately, drawing them in 2D then importing into the 3D program and spacing them correctly along the length of the ship's bottom Center Line.
So, for each half-station line in the above drawing, I: Copy
(1) and extend the baseline (short Black line) between the Station Line base and the Center Line, and radius the connection an arbitrary 12 inches. Mirror
(2) the half and Join the two halves into one Polyline. (Note: The Top curved line represents the Main Deck, not the Side Plates that extend above the Main Deck.) Create
(3) horizontal line (Blue) at Main Deck height from side to side.
I understand Station Lines do not represent the external surface of the ship but, rather, the lines of the ship inside the external plating. But, I'm using the Station Lines to represent the ship's outer surface and sized them that way above in Step 1.
Copy and inset the Station Lines
(4) 2.4", or 0.020" in my model scale. This could change, but I'm planning to skin the model with 0.020" thick ABS sheet to represent External Plating. Also I used the horizontal line to trim the inset Station Line at the Main Deck level.
Up-close illustration
(5) of the inset Station Line, the Main Deck, and, in Magenta, the 2.4" External Plate.
Question 2: With this size model (10.8" beam), should I shape the Main Deck to show its Camber? Or, would that be asking for trouble beyond what it's worth?
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4 - Station Lines.jpg [ 44.34 KiB | Viewed 2336 times ]
Step 5The Skegs and Tunnels are giving me trouble. Hope I can get a bit of help here.
Question 3: The Blue line marks where Hull curves end and the Hull becomes horizontally flat?
Question 4: The Red lines show the shape of the Skegs - even the left most Red contour?
Question 5: I don't understand what the Gold outline illustrates since it's within open Tunnel space.
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5 - Station Lines.jpg [ 111.18 KiB | Viewed 2336 times ]
The Green lines represent the Tunnel as it grows taller toward the Stern.
Question 6: The Green lines do not match up well with the Hull Station Lines. Are they not meant to match up with the ship's Stations?
Question 7: The Side elevation of the ship reveals (once the Station Lines are marked every 21-1/2 feet AP-FP) that the aft Hull begins to rise about the 27-1/2 Station mark, not about the 33 Station mark immediately above. WTH?
I've looked around online for Iowa Class Skeg/Tunnel photos. Found nothing too helpful.
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