The Ship Model Forum

L-Arsenal also offers a brass PE set specifically designed for Japanese merchants and IJN auxiliaries. There is much to like about this set. It comes with both a central catwalk modified for UNREP use (with short sidewalls, attached railings and proper ribbing on the flooring), as well as another, more typical catwalk, also with railings, that can be placed alongside the modified version and glued together for the correct configuration. It also comes with several different types of trestle supports, which are also beautifully rendered.

This was my first choice but, I ran into a few unexpected hurdles. Most were minor: the sidewalls of the UNREP catwalk are not scored, making the bending of them into position along their full length a bit problematic. Patience and good bending technique are a must. For rivet-counters like myself, the number of railing bars was also on the low side, one bar instead of three bar. There is also so some uncertainty about using which of the various trestles types should be used, and in what order. I found this particularly confusing as I can only see one general type in use along the entire length of catwalk. Again, these are extremely minor issues.

More problematic for me was the height of the assembled trestles. They were simply too short to allow the ends of the catwalk to align with the 01 deck levels at either end.

Rather than attempt a fix, I decided on a third option � styrene walkways with PE railings, trestles, piping and access ladders. It turns out that a U-shaped styrene channel works perfectly as a main catwalk, complimented by strips of V-groove styrene painted deck tan and washed with burnt umber, just like the wooden decking. I was also able to attach proper railings and brass rod for additional piping. The piping took a couple of tries. Originally, I tried to depict hem with some spacing between the lines, but the result was very uneven. I redid the piping with the lines nestled next to one another. It made for a neater appearance though, honestly, one would never know if not for the tyranny of the digital lens.

The biggest challenge was the trestles and getting the proper height. After some thought, I hit upon what I think was a wonderful solution: I separated the trestles from the Fujimi SS PE catwalk, turned them upside down, and glued the footings to the underside of the styrene catwalk, taking care to space them evenly. It worked out perfectly.

The only open question that remains is whether or not to lay down something to depict the ribbing along the bottom of the trough. I will ultimately be adding refueling hose in this space, so I�m uncertain how much of the ribbing would even be visible. I did find a length of stainless steel railing from the GMM IJN Auxiliary PE set that would work as ribbing. (Depicted, but not glued into place.)

I think the gmm railing is a good idea . Too course to be used as railing its ideal in a semi concealed area where it adds texture to the overall detail in an area.

I like your fix with the walkway. Good lateral thinking. With lots of pipes and fiddley bits I can see this is going to be impressive

It�s been a while. I knew I had been derailed but I did not realize it�s been two months since the last posting. Basically, vacation, a nasty respiratory virus, life, etc all conspired to interrupt my focus, progress, and continuity. I am only now starting to resume the build. This model has no chance of making this year�s NATS now, unfortunately.

Things began to go south when I brilliantly dropped the aft catwalk. Railings were bent and dislodged. Piping went flying. Worst of all, the brittleness of the stainless steel folds became apparent when some of the trestles snapped off. (In this regard, brass is far better as it is a more forgiving metal.) Repairs were unsatisfactory.

So, I set it aside for the time being and attempted to build the forward catwalk. While the catwalk itself was relatively straightforward, a new problem arose with the trestle footings. The forward catwalk rises with the main deck as it approaches the bow. The kit piece trestles are etched in a way so that, when used as designed, the position of the trestle pillars is slightly staggered, so as to allow the catwalk to rise in a gradual curve that parallels the main deck. However, that means leaving them attached to the kit catwalk, which really does not work with my scratch-built sections.

Detaching the trestles and turning them upside down, so as to use the footers as attachment points to the underside of the catwalk, only really works for the two trestles closest to the bridge, where the main deck remains flat. Otherwise, the offset sets them at an angle. The only way to compensate it to trim the ends, to get a roughly level trestle. It worked with some degree of success but, it really doesn�t look so great.

At this point, I�m waiting for another solution to present itself. In the meantime, I am using the catwalks as markers in my reworking of the deck piping (which will be glued down later in the process). I also finished up reworking the deck, the access hatches on the main deck, the structures that carry skylights, and gooseneck intakes.

Despite the setbacks, still looking quite nice.

Dan K wrote:It�s been a while. I knew I had been derailed but I did not realize it�s been two months since the last posting. Basically, vacation, a nasty respiratory virus, life, etc all conspired to interrupt my focus, progress, and continuity. I am only now starting to resume the build. This model has no chance of making this year�s NATS now, unfortunately.

So sorry not to see the World Cup on the list of excuses.

World Cup commenced after my travails.

I switched tacks again to concentrate on finishing the basics of the main deck. I sprayed some white paint down and taped off what will be safety lanes.

BTW, if I hadn't mentioned it before, the main deck fit is terrible. Plenty of sanding is required to get it to fit flush into the provided channels. Plus, there are guides molded into the underside of the deck that are supposed to align with the tops of two internal guides that hold down the waterline weight. At least one side has to be cut away in oder to allow the deck to lie flat without interference from these "bulkheads".

Very nice. We are getting close. Any chance of VB?

Good to have you back Dan



Jose

Thx. Sadly, no chance of this showing at VB.

I completed and painted the basic main deck over the weekend. Not bad, some touch-ups required. In retrospect, I probably should have used light grey instead of a stark white for the safety lane lines. I can do so for Kyokuto Maru. Perhaps the lines could be thinner as well but I used the thinnest Micron tape I could find at 0.4mm. I suspect that as I add ladders, piping and equipment to the deck, the lines will fade in prominence.

The deck color is still bit of an open question for the Japanese wartime merchants. Many ships, tankers included, used a sort of red-orange color (anti-rust?) paint in pre-war days. Not all retained it; there is plenty of anecdotal evidence that many decks were painted over with grey. I turned to Motoyuki-san for his advice, which was that the evidence is inconclusive, and he suggested sticking with grey to play it safe. Which I did.

I choose a dark grey for the deck, and neutral grey for everything else, again, a Motoyuki-san suggestion.

Nice job with the deck How many tons of oil did these tankers carry?




Jose

I'm not sure about tonnage capacity. The Wikipedia entry lists approx 16,100 cubic meters storage capacity for Kyokuto and Toa Maru, 14,600 cubic meters capacity for Nippon Maru.

The USN Wartime Recognition Guide states ranges of 93,000 to 103,000 barrels of oil storage for various members of the class.

I decided to work on the bow next. Most of the UNREP conversions included a port side, bow mounted sponson in addition to the stern sponson, to guide & clear oil hoses for refueling ahead. Unlike the stern, this sponson was fully enclosed by plating, with a fully rounded leading edge. The outer edge plate served as an guide. Some examples shown below (Teiyo Maru is a proto-Kawasaki type, but shows off the sponson leading edge very nicely.)

Interestingly, Kyokuto Maru, and probably her Group 1 sister, Toa Maru, did not have this forward UNREP sponson. Looking at the photo of her refueling Hiei on page 4 of this thread, or in the photo her refueling Hiryu below, it seems as if a portion of her port side forecastle bulwarks is either removable or, hinged to pivot back aft, so as to allow refueling hoses to be passed forward.

Sizing wise, the Fujimi kit part is far too small, by at least half, and only for a platform instead of a full sponson. For Kenyo Maru, I just used styrene round and sheet to form the sponson, along with a little putty.

The kit molded hawse pipe coamings are misshapen. I removed those and scratch built new ones. I tried to use a heated metal point to allow the plastic to form into a round ridge around the entry point but, it
didn't work out. This approach has worked in the past but, I've lost or misplaced the original tool that I'd used back then. So, I had to round off the end of the smallest styrene rod with a hollow running through it that I had, then slice off the ends and glue those on. These may be slightly imperfect. I'll try to even it up. I do know that when covered with paint and partially obscured by an anchor, it will be hard to notice any imperfection.

Really fine work! These are going to look so good when they are finished. MosquitoCon is in 7 1/2 months!

Gee, at this rate, it will done for MosquitoCon 2016

I completed the painting of the horizontal portions of the forecastle and aft decks with dark grey. Some vertical surfaces have gotten coats of neutral gray; others have yet to. Nothing is glued in place aside from the aft deck. Some horizontal surfaces have already been taped in preparation for applications of paint to the vertical surfaces.

Dan K wrote:The USN Wartime Recognition Guide states ranges of 93,000 to 103,000 barrels of oil storage for various members of the class..)

Did you see anything in tonnage #s i just want to see how well they did next to the American counterparts, although i think a little over 100k barrels left alot to be desired. Great looking tankers though, but to be honest being on an oil tanker was the last place i'd like to be on at that time.



Jose

Jose, nothing is listed in tons. However, I know that there are several different conversion calculations available, depending on how you define ton; say, displacement vs. freight. It depends on exactly what sort of measure you want. I'm sure there are board members far better versed in this than I.

A partial explanation from Wiki (fyi - long ton = 2240lbs.):

"The displacement, essentially the weight, of a ship is traditionally expressed in long tons. To simplify measurement it is determined by measuring the volume, rather than weight, of water displaced, and calculating the weight from the volume and density.[12] For practical purposes the displacement ton (DT) is a unit of volume, 35 cubic feet (0.9911 m3), the approximate volume occupied by one ton of seawater (the actual volume varies with salinity and temperature).[13] It is slightly less than the 224 imperial gallons (1.018 m3) of the water ton (based on distilled water).

One measurement ton or freight ton is equal to 40 cubic feet (1.133 m3), but historically it has had several informal definitions. It is sometimes abbreviated as "MTON".[14][15][16][17] The freight ton represents the volume of a truck, train or other freight carrier. In the past it has been used for a cargo ship but the register ton is now preferred. It is correctly abbreviated as "FT"[citation needed] but some users are now using freight ton to represent a weight of 1 tonne (1,000 kg; 2,205 lb), thus the more common abbreviations are now M/T, MT, or MTON (for measurement ton), which still cause it to be confused with the tonne, or even the megatonne.

The register ton is a unit of volume used for the cargo capacity of a ship, defined as 100 cubic feet (2.832 m3). It is often abbreviated RT or GRT for gross registered ton (The former providing confusion with the refrigeration ton). It is known as a tonneau de mer in Belgium, but, in France, a tonneau de mer is 1.44 cubic metres (50.85 cu ft).

The Panama Canal/Universal Measurement System (PC/UMS) is based on net tonnage, modified for Panama Canal billing purposes. PC/UMS is based on a mathematical formula to calculate a vessel's total volume; a PC/UMS net ton is equivalent to 100 cubic feet of capacity.[18]

The water ton is used chiefly in Great Britain, in statistics dealing with petroleum products, and is defined as 224 imperial gallons (35.96 cu ft; 1.018 m3),[19] the volume occupied by 1 long ton (2,240 lb; 1,016 kg) of water under the conditions that define the imperial gallon."