The MOGAMI class cruisers were the first releases in the 1/700 scale waterline series about twenty-five years ago. I can still remember the excitement when I opened these kits and saw the flyer with the Japanese text and a perspective painting of the entire Imperial fleet. Would they really be doing all of the WWII Japanese Navy? Soon afterward we learned that there were four companies involved and they did indeed plan to do the entire fleet The project has never been completed but all of the important fleet units except the light carriers are now represented. Since the project is still slowly continuing, it has actively extended over the intervening years. Model companies improve as they go, just as modelers do. It should therefore come as no surprise that the SUZUYA, KUMANO, and MOGAMI kits are nowhere near the standard of the more recent 1/700 scale releases. Even though they are made by Tamiya, a company known for quality in ship kits, due to their age, they are very simplified and have a lot of minor inaccuracies. The MOGAMI kit is the worst of the three as the basic parts are the same as for the SUZUYA version, with the addition of extra aircraft and the replacement of the aft turret with an extended aircraft handling deck. To understand why this is a problem, one must know a little about the ships these kits purport to represent.

The terms "light" cruiser and "heavy" cruiser originated as a convenient method of classification spelled out in the terms of the Washington Naval Treaty. Light cruisers were defined as ships armed with 6.1" guns or smaller, regardless of the ship size. The heavy cruiser was defined as being armed with guns larger than 6.1". In practice most heavy cruisers were armed with 8" guns or their metric equivalents. Under the rules, after the London treaty conference, treaty cruisers were also limited to a tonnage per ship of 10,000. Japan was near her allowed legal limit with regard to heavy cruiser tonnage. The treaty terms did allow for replacement of older ships and several light cruisers were nearing the age where they could be scrapped and replaced with new tonnage. By combining the remaining tonnage allowance, about 12,000 tons, plus tonnage gained by the scrapping of older ships, it was calculated that four new 8,500 ton light cruisers and two additional ships of a modified design could be built and still be in compliance with the treaty agreements. These would become the Mogami class, (4 ships) and the Tone class (2 ships).

In the late twenties and early thirties, the Imperial Japanese Navy built a series of eight very large and powerfully armed "Type A" (heavy) cruisers, the four TAKAOs, and the four NACHIs. The MOGAMI class was a design continuation of these ships in style and layout, differing only in the type of armament specified. They were in fact designed from the beginning to be able to be upgraded to 8" gun ships should the political situation allow it. It should be noted that all of these ships were looked upon with considerable suspicion in the West as it was stated by both American and British naval constructors that the TAKAO and NACHI class HAD to be exceeding treaty limits in displacement. When trying to design an equally powerful reply they found it impossible to arrive at the same combination of armor, armament and size and still remain within the 10.000 ton limit. Although officially denied, the Japanese ships were in fact well in excess of the legal treaty limits. Several innovations were tried with the MOGAMIs to reduce weight and attempt to comply with the treaty limitations but without sacrificing any fighting power. Electric welding was used extensively in their construction, a pioneering effort that resulted in serious structural weakness. All of the boiler uptakes were trunked into a large single funnel. After the capsizing of the torpedo boat TOMODZURO during a fleet exercise, the design was revised and top weight was drastically reduced. The original massive bridge, (similar to the TAKAO), as designed for the class was discarded and a new more compact design was built. In spite of these changes the MOGAMIs were still too heavy and were well over the treaty specifications. Soon it would not matter as Japan withdrew from the naval limitation agreements and pursued a new design program free from restraints. In light of these events it is tempting to regard the violations of international agreements regarding ship design as just political duplicity on the part of the Japanese Government. Perhaps this is partially true, but there were other factors that must be considered.

As a military force, the Imperial Japanese Navy was a relatively new creation. In the formative years before the turn of the century, in order to catch up with the West, Japan relied heavily of foreign assistance. The IJN was organized and trained by the British Royal Navy and many of the ships came from British yards. A military alliance was in effect between Great Britain and Japan which was entered into by both parties to counter Russian ambitions in the Far East. Japan honored this agreement and declared war on Germany during the First World War. Japan seized all of the German protectorates in the Pacific as her contribution to the war effort but did not send any troops to France. The Japanese Navy was present in European waters but not to the extent that was requested. After the Great War Japan emerged as the most powerful naval force in the Pacific. Tensions increased steadily between the United States and Japan and, under pressure from Washington, Great Britain did not renew the mutual assistance alliance with Japan. Japan's political isolation increased through the twenties and become almost total once she embarked on the military misadventure in China. The effect of these events upon the Japanese Naval constructors was highly detrimental. While their experience was limited, they were confronted with a very rapidly changing technology, increasing sizes of ships, and were "out of the loop" with no free exchange of technical knowledge with their peers in other nations. It is for this reason that Japanese ships have their unique "look", quite unlike any other navy. Japanese designers had to come up with original solutions with no outside input. Some were extraordinarily successful, some were not. Calculations of new designs were also affected and there may well have been a very large portion of "honest error" in some of the excess tonnage results.

This could certainly be true in the case of the first large ships, the TAKAOs. After that, it would be self-perpetuating as the Navy would be reluctant to give up the power gained by accepting inferior designs. Deception and duplicity would then be a factor in the public pretense that the NACHI and MOGAMI class ships were in compliance with the treaty limitations. They were not, and the Navy knew it, but was unwilling to sacrifice anything in succeeding designs in order to bring them into compliance.

The weight saving attempt by using electric welding in the construction of MOGAMI resulted in a serious weakness. After her high speed trials the hull was found to have suffered warpage, the bow was twisted and the main turrets forward could not be trained. MOGAMI and MIKUMA were both drydocked for extensive reinforcement. KUMANO and SUZUYA were redesigned as a result of the problems encountered in the first two sisters. Some of these changes were external. The SUZUYA/KUMANO pair had a smaller bridge structure at the 0l level, more compact, with a pair of directors free-standing on the main deck rather than being attached to the bridge extensions as in the first two ships. The trunking arrangements for the funnels are also different, similar from the profile view, but different from above. Engine room vents are different in both style and locations.

The point is, all three kits have the same parts for the bridge and hull, and thus are only correct for the KUMANO or SUZUYA. The 0l level bridge structure is molded as part of the hull, so changing it for the MOGAMI is not easy. A lot of the kit detail is very simplified and there are some errors around the aft superstructure that need correcting. The details and suggestions that we will be looking at are fairly easy to accomplish and can really make a big difference in the final result. It is not really a bad kit, but is in need of some refinement in order to make it look at home with the more recent kits in the 1/700 waterline series. The Skywave weapons sets make this a much easier task since they include some of the parts that Tamiya did badly. The Gold Medal Models IJN Cruiser/Destroyer sheet has parts for these kits - searchlight towers, boat crane, and catapults, that will also greatly improve the final model. GMM is in the process of revising and improving all of their photo etched sheets so the new version may be even more useful for this project. The IJN sheets have not yet been revised but will be in the near future.

The funnel is prcbably the worst part of the kit. The detailing is heavy and crude. Those heavy rounded bands encircling the funnel are meant to represent foot rails used for maintenance by the crew. In this scale they would be no more visible than deck safety rails and are thus grossly overstated. These should be completely filed away. Replacement is optional. The funnel will look much better with NO railings, rather than with overseale ones. The funnel grills are solid and can be greatly improved by hollowing out the tops and using sprue or photo etch to construct new ones. The funnel is a prominent feature and careful work here will really pay off.

The bridge is simplified in many ways, particularly at the upper levels. The real ship has open areas at the rear of the upper bridge levels. The kit parts are basically the right shape but lack detail and everything is molded solid to save on tooling. The platform levels are also too thick. The drawings show what the problems are and they are not very easy to fix.

The gun tubs for the twin AA mounts should be open inboard. Careful file work can fix this problem. This style of tub molding for the large 12.7cm AA mounts is a common problem in all of the early waterline series, shared by the TONE, NACHI and TAKAO class kits. The gun mounts are also crude and not shaped properly but these can be replaced by the better Skywave parts from the E-5 set. The Skywave E-7 set will also be handy for all of the small AA guns, twin and triple 25mm mounts, paravanes, searchlights, and various small details such as hose reels.

The aft superstructure is simplified as is the main mast tripod. Both of the masts should be rebuilt using sprue or brass rod. The Jake float planes are not too bad, but in more recent moldings, have suffered from tooling wear in the passage of time. The Skywave aircraft are quite good and if used on all of the appropriate kits gives a consistent look that is important in viewing a collection of models. It is important that aircraft of the same type look the same from ship to ship and for this reason alone I would suggest settling on one kit source for these.

That about covers the basic improvements needed. More can be done, such as adding a scratch built practice loader aft of the rear turret, reworking the searchlight platforms beside the funnels to a more correct shape, re-shaping the engine room ventilators, and of course, adding railings, stairs, and ladders at all levels. Bridge window areas can be opened up and open window frames added using photo etched vertical ladder stock. Never throw away unused photo etch parts for they can be used as "raw material" to simulate details and structures far beyond the purposes they were designed for. GMM, Tom's Modelworks, and Flagship Models sheets contain a lot of very useful parts. Quite apart from their intended design applications, these parts should be regarded as "generic" structural shapes that can be adapted for any project.

1/700 Scale Drawings

15.5cm main gun turrets Built in rangefinder is correct for Turrets 3 and 4, Turrets 1, 2 and 5 did not have them	20cm main gun turret The Mogami class was updated to re-classify them as Heavy Cruisers. Rangefinders are only for numbers 3 and 4 Turrets	12.7cm AA Guns Note splinter shielding is cut down inboard.	Funnel and forward AA gun platform

Basic bridge structure	Bridge complete with directors, searchlights, railings etc.	Details of main mast, boat crane and aft superstructure

This article originally appeared in Plastic Ship Modeler 1995/4 and is reprinted here with the permission of the author and editor.