Description: Description: Description: Description: Description: Description: Description: Port Polar Bear

- Hyuga -


INJ Hyuga Ė Tyler

5.5 units, 26 seconds, Japanese battleship


The Ise/Hyuga were built as improvements on the design of the Fuso/Yamashiro battleships and were completed in the late 1910ís. They similarly featured 6 turrets each with two 14 inch guns which was theorized to have advantages in the amount of total projectiles per minute the ship could fire broadside with additional advantages of each having independent fire control as such to get a higher number of shots on target sooner and keep a higher number of guns firing in the event of the loss of a turret in combat. The flaw was that in reality the center turrets had limited firing arcs and also that there were multiple magazines spread out throughout the ship making protection more challenging. The successor battleship in the Japanese Navy was the Nagato, which was the first ship in the world to mount 16 inch main guns and they were placed two each in 4 turrets in in sets right next to each other making it more possible to concentrate the protection. The ships were heavily upgraded during the 1930ís adding armor bulging and length as well as substantial superstructure changes. The two ships were again heavily modified after the battle of Midway to include posterior flight decks as the stern most 2 turrets were removed as a response to significant aircraft carrier loss.


Both the Fuso and Ise class are interesting ships in out hobby because of several advantageous design features. The multiple turrets allow for several options for gun placement including the option of creating a very dangerous stern. The ships have two twin rudders and four shafts. Also, they have a heavy amount of casemate guns for protection against stern guns. The disadvantages are that they are 26 second ships that are about as large as a ship can be before it reaches the threshold for 24 seconds.


I received this boat in a state of refit. It was a wood hull ship. The original builder had done a fairly OK job with certain parts of the wood work but other aspects were less ideal. Also, concrete sealer was filled between the ribs for water channeling instead of something lighter like balsa which has been my preferred method. This article will document the rebuilding process.



As I got to looking over the ship and imagining what work needed to be done I started to make a mental list. When I received the hull the bow sections of concrete sealer had already mostly been cut out leaving the ribs and a small amount of concrete sealer behind, I prefer balsa there so that would need to be cleaned up and new balsa cut and sanded and sealed which is actually pretty easy. The rudder posts and dummy shafts were in but the drive shafts had already been removed and the stern was partially worked on, I ultimately opted to cut out the dummy shafts as the whole back end needed to be redone any way. Also I only had 2 of the deck sections so at the minimum I will need to replace the missing ones but it was sort of set up to have as many as 5 removable sections, I prefer 3 at most so was planning on changing how that comes together. The very bow of the ship can probably be completely sealed from the top and not removable at all. The bulge stringer had been partly removed on the port side, I planned to remove it all and replace the wood with aluminum, and would want to do the same for the higher up stern most stringer. The forward most sub-casement deck level was not continued to the next rib as allowable in our rules and the section under the casements should only be 1/8 inch thick and was built up a bit too much so that needs to be re-sanded. Also, I think the stern subdeck is too narrow which can cause problems with deck seal if there isnít enough overlap, so sanding down and redoing the subdeck is also on the list, I can probably live with the bow subdeck. Additionally though it is hard to see in this picture, there is bulge water channeling made from the concrete sealer which I would usually do in balsa and as such planned to rework.



This is a fairly good look at the water channeling amidships. The center of the ship has a water channel to allow water to flow bow to stern under the other internal components, which is desirable. The next level higher of darker gray you can see where the ribs naturally divide smaller box like components where concrete sealer was filled, preferably this would be a lighter material. The next level up/out is a lighter grey that is also concrete sealer in the bulges, in my opinion it is also too heavy but also too far towards the middle of the ship. Generally speaking I like to be in more control of ballast weight. Iíd rather put lead along the outsides of the ship and screw it down so the ship is more adaptable to future modifications. And another principle of ship design that I like to keep in mind is that if you have room for extra ballast weight it should be battery if possible, so it is functional. For these reasons I like to keep water channeling material light. Another important principle is ship stability. Ships preform better if the weight is as wide as possible along the bulges for the width dimension, and as close to center as possible for the length dimension. For these reasons fixed ballast in the form of water channeling is less favorable to me.



This picture was taken as the ship was getting closer to being cleaned out of the concrete sealer.




This picture shows how the concrete sealer was removed from the entire ship down to the ribs and the wood layer that was placed on the bottom of the ship. This process was extremely laborious. I used a combination of Dremel cut off wheel/sander/routing bit as well as a hand held Ĺ inch belt sander. It was very messy and I used the shop vac extensively as I was grinding the probably toxic material out.



Here the balsa was cut to fit and glued in then sanded to fit the shape of the left behind ribs.



An angle from inside the boat shows how the balsa blocks are fit to shape on the inside. The for bow was built up to ľ below the open window which was about 1.5 inches from the benchtop. The next level back will probably hold the radio box so I didnít want to build it up quite as high. It is not quite 1 inch tall. Ultimately this will be filled over with epoxy. I intentionally leave some small cracks at seams so the epoxy will fill in all the spaces it needs to. And seal everything together in one block.



Here is the mid section water channel and bow section is visible too. There is a white tint to the epoxy because of microbaloons. Fiberglass cloth is used over the balsa in the bow so the incoming shots donít do damage.



I was not happy with the amount of deck rim in the stern part of the ship so I opted ot repace that whole section. Most of the decks were not with the ship any way.



I sanded the top ľ inch of the 3/8 inch deck/subdeck assembly leaving just a 1/8 inch thick portion.



The 3/8 became 1/8.



I then traced a new 1/8 inch thick sub deck and glued it in.



I did the same for the deck that I did with the sub deck. This is the rough cut and will be sanded smooth.



This picture shows the three sections of 1/8 inch coming together, bottom was origional, middle is the new sub deck with much wider overlap, and top is the new deck and deck rim. This section also shows how I use aluminum 1/8 inch stock to bend an armor belt into place. This is pretty teadious but is very strong compared to wood.



The bow section was done a little different. The need for a tight deck seal is not as great in the bow so I just left the deck rim and cut new 1/8 inch decks to be inserted into the slots that were already there. The bow section in this will be permanantly glued down, minimal need to access that space in a larger ship. The bow most section will have the 2 turrets, can be removed but hopefully less of a need to do so under normal battling circumstances. The section in the bow middle under the superstructure will be one of the primary access points. The stern most section will also be removable but generally need to be moved less often. The midship stern section will also need to be routinely accessed to change batteries/etc. I donít usually like four sections and prefer 3 but the central turrets and centrally located step leavs fewer options.


This is also a good look at the super structure and barbet locations though the barbets are not the correct height here.







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