Japanese Class A 1/16

[Ken_NJ]

Wow, this is interesting hearing all this. Something I never heard before. Keep up with the history lesson! Maybe it's own thread. And always like watching your work Manfred.

[Von Hilde]

Manfred, thats the way the Japanese built them in the Kure shipyard. 3 section modules, from different subassemblies built in different shops. Some were shipped in sections to secret IJN bases in the Pacific. They were assembled at the destinations, such as the Allutian islands and Baha Mexico. Some were assembled and deployed from surface vessels as well. I assume you are aware that the boats were dynamic divers and no balast system. They sat low in the water, at rest. Some of the animated videos of the C class mother subs, depict them launching from below the surface. Didnt happen. The launch procedure from the Mothers was to get within target range which was relitivly close because ther wasnt sufficient battery to power to run at speed, One thing being the drag underwater would slow the boat more when the tower was under and required more power, which would deplete the batteries quicker. Once in position, the mother would remain submerged until dark, then surface. The mini crew would board the boat and launch crew would release the tiedowns from the mother deck. The mother would just open the flood gates and dip away from the semi boyant mini. The mini would then make the first leg to the target on the top. Basiclly tower slightly above the surface so the Officer could see thru the observation ports. Running on low power at a couple knots untill time to dip under to perriscope depth on the torpedo run. They didnt have much of an operational range. around 30 miles at cruise speed, so the idea of making it back to the rondevous point was slim to none. The attack force of the 5 Pearl Harbor boats had a contingabcy plan of escape. Infact it is now come to light, the crew of the 5th boat that was never found, actually ran aground at Pearl City during the evening after the attack around 8 pm. They managed to signal the I24 that the had success and were going to plan B. There were maps found aboard one of the minis that ended up on the beach, showing a "Safe house" location, in Pearl City. Also ther was an account of a Navy pilot that flew in from the carrier that was inboubd to Pearl harbor. He was on his way to Sundy service athe the Navy base and stumbeled into the attack. The Airplane he was in was unarmed and was shot down by a couple zeros. Crashed on the highway in Ewa beach just outsid of Pearl.. He parachuted safely and was trying to get to the base, as the attack was still in full force. He flagged down a truck leaving Pearl city, that was in a hurry. The driver. a Japanes American had a passenger, who was Japanese as well, but was soaking wet and in his typicle Japanese underware, basiclly a diaper kind of cloth, The driver refused to give the pilot a ride to the base and speed off. The significant detail of the underwar is, the escape orders were to strip off all uniforms down to the underware and leave everything aboard the boat. Besides the paper containing the plan of escape there were uniforms found aboard some of the recovered subs but no bodies. A little history lesson for you to contimplate while you build one.

[MFR1964]

Thanks for the info Von, weldinglines will always create problems, unless you have the original shipyard drawings, even then you can go wrong, i hope David can do me a pleasure by digging up the master they made and take pics from all sides, giving me a accurate view.
Let's hope he can find the time for doing that, i know his plate is fully overloaded with Mike jumping on his back screaming "more, more, build more ******, and faster!!!!,.
For now i'm still covered by foamdust, within a few days all parts will be ready for glueing, i want to build her at first in three parts, front section, middle section and rearsection, when every section is ready i will marry them into one piece, this way i have some room for adjusting her symmetrical, with foam you don't have a choice, the best way of building this boat is the way David did, some nice straight pieces of wood.

Manfred.

[Von Hilde]

Manfred, the weld lines that I used were an interpilation of sources, mostly from photos. Relying on the drawings, only for a guide. You are correct in fact the actual boats differed individually, as well. The 5 Pearl Harbor boats were unique in a class, by themselves. They were almost identicle, except for markings. All other boats after Dec 10 were up graded, because the IJN thought they all failed due to possible design flaws.( Dec 10 was the rondevous date for any survivors that could possiblly be left, could hook up with a waiting Mother ship, south of Oahu.) Originally the designers assumed it was the net antifowling guards. (Not Net Cutters, as most people call them.) They wern't for cutting, but diflecting the Cables that held the buoys for the anti torpedo netting that was suspended below the surface, So various mods were made on all the type As in the rigging as well as the armor on the towers. So basiclly saying that if you rely on existing drawings, from anyone, they will be based on a surviving relic that is most likley a display. These displays are all cobbed together from various war torn boats off the bottom. None are compleet except for Kazuo Sakamaki's Ha19, and that is not even absolutly correct after it was revovered, on Dec 8. The Prop cage antifowling apparatus had been run over by a destroyer, and then ran aground on the reef after it broke free of the rocks, they made it to the beach on the east shore of Oahu. The USN recovery team the nest day dragged it off the beach with tow cables hooked up to the jumper wire. This further dammaged the original rigging and fowling system. No one cared it was just a hunk of beaced junk. Somebody in the war department. thought it would be a good War Bond project. Restoration for the war bond tour at Mare Island shipyard in 42 left off the end of the prop guard, and it still missing. When it was sitting at the base in Key West, I spoke with Kazuo about the condition of the relic as it sat in 1990, and he said many details were overlooked, one being the antifowling and the other was the color. So, the only surviving prop guard in good shape is on the ha8 which Gene based his drawings on. The h19 had drewings made by a US Navy Commander that took the measurements off the boat as it sat at the KW merritime museum its last resting place where it was still all together. Shortly the Nimitz museum, aquired it and took it completely apart for shipping from KW to Texas by barge. I purchased a 1/72 scale model of the H19 that was made from those drawings the Naval Architect drew. Fine Models, a Japanese company produces this boat. Listed as A-Target, IJN Type A midget(Pearl Harbor) Very good representation, and detailing of hatch and deck plate placement. Well worth the investment and a wealth of knowledge. Even in the instructions not just for the drawings but the text as well. (If you understand Japanese) or know a local Sushi Chef, as I do both. Very interisting tacticle information on the attack and positions of where and when all the boats were accounted for, Things the history books had all wrong, as to what happened. Happy New Year BTW I could be a good one.

[MFR1964]

Von,

The same story for me, sometimes it's good to step back from making models, gives you a fresh look for the future, as for the To Do list, i don't mind, it will return every year, gives me a excuse for not building models.
Building the plug was something i delayed too long, have to do this in the winter so i can laminate her with a epoxy skin in the spring.

I do have a question for Gene, as i look at the drawing, the weldinglines are different to the model you've made, is there a reason for that?, or do the weldinglines differ by boat?, i also wonder if there are pictures how the boat is being split up, i prefer the vertical split into three parts, so transport will be much easier, it even gives me more access to all parts.

Manfred.

[Von Hilde]

good to see your progressing on that now. I have been taking a long break from the models these last few months, as well. My wife doesnt give me a To Do list. The reason no need for a list , because I have to fix everthing thats broke. She said just keep working till I dont see anything left to do. You know if there is a list and you cross one off, two more amazeingly appear.

[MFR1964]

For now i'm playing around with foam, i don't own a woodlathe so i went the foam way, did this before with the type XVIIb,



At first i took some measurements to get me the right diameters, this was depending on the thickness of the foam, about 6 cm, took the complete package and drilled a hole right in the center, by using a threaded bar with nuts i can clamp the foam between both ribs.
Used a sawblade to get the rough shape and a sandingblock to get the part smooth,it also could be done with a melting wire, but once again, it's not in my toolbox, i've got to improvice.



After a few evenings you get this, started to build up the rearpart, those lines on the foam are used to place them in line.



The middle section was easy, made five equal parts, used the drawing for checking the length.



All parts in line for a dryfitt, next week i'll start with the frontpart, got myself some days free from the office, so it should go fast, unless She Who Must Be Obeyed has some jobs to do, ssstttt!!!!!, never mentioned that, if you know what i mean, wink,wink,notch,notch!!!

Manfred.

[MFR1964]

Scope up!!!!

There is dust in the Cave, wait and see

Scope down!!!

[Von Hilde]

Excelent as would be expected from you Manfred. That is beautiful. I havent done much on mine, except research on the type A. and hull detale differances. I have changed the scale on my project boat to 1/19th to keep the model under 48inches, so basiclly now have two towers. one is the 1/16th that I started with and a slightly different version in 1/19th, which is spacific to the H-19, Mr Sakamaki's boat. I dont want to hijack this thread, so I will be posting the progress on the hull on a new thread, under 1/19th scale Pearl Harbor Miget.

[MFR1964]

It has been a while, but i'm back on the track, She Who Must Be Obeyed is pleased with her new garden, and i can focus me again on the build,





Added the reinforcement strip at the back, and used some half cutted tubes to imitate both the periscope housing and the entry tube under the conningtower hatch.




Made a beginning with the copper sheeting, instead of using glue i went mad with the soldering iron, giving me a real live weld.



The other side was pretty much the same, first the dryfitting before i could start with the soldering.



I went ahead with making those reinforcement ribs, and drilled all holes for fastening the rear plating, for now i have to make the rear plating, crawling ahead.


Manfred.

[He Who Shall Not Be Named]

Hello
Question for: He Who Shall Not be named. Still waiting for the plan/drawing you said you sent me.

Please let me know.

Thanks
George

Thanks for the reminder, George.

M

[george]

Hello
Question for: He Who Shall Not be named. Still waiting for the plan/drawing you said you sent me.

Please let me know.

Thanks
George

[He Who Shall Not Be Named]

Excellent, excellent work, Dave. You have no fear!

M

[Von Hilde]

Little more progress on the hull and tower. Made a wire frame for the front section and covered it with aluminium. Made the hinge for the hatch. Don't really know why I made it operational, except that it was just there. I'm to the point of thinking functional torpedoes. Or at least the option of them later. Making the tubes and mounts while it's still accessible. This will take some research and ingenuity. The bow will be fun to bend. First have to figure out how the split will operate. Magnets or fasteners.

[Von Hilde]

Transmission/gear box access hatch, with the actual hatch, plus boiler plate cover, underneath. The aft lifting eye, is the hold down screw. Soldered a tab with hole, made from flattened wire and drilled to the brass screw. Tapped a hole in a cross piece in the hull. Boiler plate, is a scrap piece of 1/24th scale plate from some old armor model, long gone. Rivet ring is beer can, hand tooled. Weld seams are copper wire strands for the lateral seam and steel electric guitar E first string. .010 gauge. CA tacked, then JB weld, and sanded