The Ship Model Forum

BC,

You have hull lengths of 887 feet and 893 feet - a six foot difference. No problem! Steel expands when it is heated, so the length of ships changes as the temperature changes. An 887 foot steel hull will expand to 893 feet with a temperature change of about 600 degrees Celsius. So the Iowa would be 887 feet long here on Earth and 893 feet long on Venus.

Seriously, you should CAD model in actual units - feet, meters, furlongs, whatever. This avoids scaling and round off errors, so you can just enter the dimensions given on the drawings. Then, after the CAD model is complete, you can change the scale to whatever you want to build.

The Fore Peak (F.P.) and Aft Peak (A.P.) are the lengths of the working Load Water line (LWL) - where the hull cuts the water - and not the actual length of the ship. Note: often several different waterlines are given, but the Load Water Line (maximum load) is the normal reference, and the Design Water Line (DWL) is where the ship would float with no load. The F.P. and A.P. are sometimes referred to as "perpendiculars" and are the normal reference length for the ship. The Fore Peak is also station 0 (zero) and the Aft Peak is the last station. However, the hull actually extends forward of the F.P., and sometimes negative station numbers (1/4, 1/2, 3/4, 1 etc.) are given. And the hull extends aft of the A.P. If the hull has a flat transom this might be called the E.P. (End Point) - the aftermost point of the hull.

It is pretty common to see different hull lengths given for a ship type. The blueprints may call out a specific length but the hull actually is whatever the shipyard built, and different shipyards and different builds often resulted in different lengths. Remember, during WWII the yards were churning out ships as fast as they could and a few inches didn't matter. So you can pick any of the given lengths and be close enough.

And, of course, hull lengths do change with water temperature. Cold rolled steel has a coefficient of thermal expansion of 7x10-6 inch/inch/degree F. For a water temperature change from the Arctic at 32F to the equator at 90F an 887 foot long steel hull will expand about 7.5 inches in length (at 1:96 that is a difference of about 0.078 inch). So if you really want to get picky you need to decide what water temperature you want to model.

Phil

PS. The USS New Jersey Booklet of General Plans (November 1984) gives the length overall as 887' 8-3/4" and the length between perpendiculars as 860' 0". Wikipedia says the Iowa was 887 feet long and 861.25 feet perpendicular to perpendicular (F.P. to A.P.) but who knows where they got that number? Navsource says it was 887' 3" long. A German site says it was 889 feet long - wonder if they were counting the trash chute? Dictionary of American Naval Fighting Ships (DANFS) says it was 887' 3" long.

At 1:96 the difference between 3" and 8 3/4" is about 0.060" or 1/16". On a 9 1/4 foot long model hull that really isn't very significant.

DrPR (btw, is this thread still alive? Sure would like to see more building information),

I'm new to shipbuilding, would you please check my drawing information? I downloaded the NavSea drawings for BB62 1984 (my project is USS Iowa). I loaded the Outboard Profile drawing into my CAD program, set the LOA hull points and scaled the line between those points to 887'-3''.

The AP-FP distance (stations 0-216) is 864'. The deck length to the rear of the AP marker is 3'7", the deck length forward of the FP marker is 19'-8" for a grand total length of 887'-3".

However, on the drawing the AP vertical line does not meet the hull at the waterline, it is four feet past that point. And something else, the drawings in the Dulin and Garzke book "Battleships" shows Iowa with a LOA of 893. Must be an editing/printing error.

Thanks much.

Great background information! Thanks for the insight.

Frames and stations aren't the same as you have guessed.

FP and AP are fore most and aft most points of the normal load water line.

Stations are equally spaced between FP and AP. If you know the distance between FP and AP and the number of spaces between stations, divide the FP-AP distance by the number of spaces to get the distance between stations. The distance is not the same for different ship types.

Hulls were designed based upon stations, and are defined numerically in the Table of Offsets by length/width/height points at the hull surface (inside the plating) at stations. This is far and away the most accurate definition of the hull - much better than drawings.

After the hull shape was determined on the stations the frame spacing was decided and the frame shapes were based upon the hull design in the Table of Offsets.

In some cases cribbing was set up in the shipyard ways using survey techniques to position the supports according to the Table of Offsets. Then the hull plating was laid on the cribbing. After this the actual ship frames were constructed inside the hull plating. So the hulls were constructed from the outside in! Of course the parts of the frames were prefabricated in the lofting areas and fastened together after being placed inside the plating. This is why blueprint dimensions are defined to the inside of the hull plating.

Phil

Now that I have the body plan, I need to know the spacing of the frame stations shown. Can anyone help me understand how the numbered stations (FP, 1, 2, ....etc....., 39, 40, AP) relate to actual locations along the keel? AP and FP are obvious, but the other numbers do not correlate with any known frame dimensions. Are these evenly spaced? Thanks.

Chuck I have a body plan drawing. Send me your e-mail and I'll shoot it your way

This looks great and gives me some inspiration to begin a similar BB-64 build project. I'm now in the process of digging through the original ship drawings to create my frame profiles, but have not come up with any front or rear views which show the hull profile. Have you been able to find any such design views?

Chuck

Here are the pics that I promised. Ignore the mess on my work bench

Thank you all for the replys and info. It's been a busy week last week. All the frames have been glued up and just started to sheet the hull. I'm using 1/16" balsa wood for the sheeting.

Last year sometime? Someone created a hull master plug ( in these pages) to glass over by filling the spaces between the frames with foam, but I believe they used rigid foam and cut/sanded down to the frame level thence covered with fiberglass. There is a "non-expanding" Great stuff, but it does expand a lot, just not enough to generally break windows and force door jams out of line. In 1:96 1" foam would give you a spacing between every two frames or 8' on the model, 2" about 16' or four frames. Not of course allowing for thickness of the frames.

The point of the planking is to fair over the frames and not apply it's own ideas about what the shape of the ship should be or become.

Good luck with however you accomplish your hull!

Regards: Tom

Planking on the inside seems like a lot of work. Why would you want to? A resin coating on the inside will seal and strengthen the planks. Some fine fiberglass cloth will add more strength if desired for a working boat.

that was my thinking but wanted to make sure. thanks

Hello,
You don't want to use expandable foam... Its not stable, and WILL expand under heat. if you put it in a confined space, it'll expand and destroy anything that confines it.
Best regards
Brad Newland

Time for a weekly update. Most of the frames are glued up from frame 220 thru 110 (11 frames cut out squared away), Should have the rest up tomorrow. Has anyone done a planking on the insides of a frame as well as the outside? also haven't seen this on the board or didn't find it, was to use Spay insulation like Great stuff to go in between the outer hull and inner hull. any thought on that. Will post pics tomorrow.

Thank you all for the advice. I actually though of going to 72 scale but two things are hindering me. 1 is transportation to the lake. I have a 5'x9' trailer so that's no problem on the 96 scale, and two, the missis would have a field day if I built something that big.

I already have the frame cut to size and dry fitted on the keel (using 1/2"x1/2" oak for the keel and going to cut the insides of the frames later this week. I plan on updating at least once week and post pics whenever I can.

my inspiration and motivation was from Ron Horabin (ARH) USS North Carolina 1/96 build among others.

a 1/72 scale fibre glass hull is available from Southern Cross Models here in Australia http://www.southerncrossmodels.com.au/iowa.php

But getting it shipped would be pain.... Scratch building is fun!! The 5" mounts and Tomahawk ABL's are available in resin from APSmodels here in Oz too..

Here is my mates BB63 on Saturday....

Cheers Bruce

Welcome to the big scale club!

Some threads over at Warship Models Underway that might interest you.

http://www.wmunderway.8m.com/cgi/yabb2/ ... 1358297945

http://www.wmunderway.8m.com/cgi/yabb2/ ... 1351998834

http://www.wmunderway.8m.com/cgi/yabb2/ ... 1392981263

The 4th pic down is me and my New Jersey.
http://www.wmunderway.8m.com/cgi/yabb2/ ... 1386481788

Lot's of resources available for these ships if you don't want to scratchbuild everything.

My approximation is the difference is between 300 lbs and about 130 lbs at full displacement. Even the smaller one nudges toward 10 feet long!

Looking fwd to the progress!


Tom

Ambitious.

It'll be interesting to watch your progress mate...why not go 1/72 scale?

After reading majority of the post here and following the great builds that I've seen, I'm going to throw my hat into the ring and start scratchbuilding the Wisconsin. I'm going to use the 1980's era since that's when I've served on her.

These are what I want to accomplish with the build.

Rotating main guns and elevation
Rotating secondary guns
Speaker and mp3 player
Timeline. I plan on having the hull seaworthy by the end of August and rest in two years.