yvesvidal

Greg, Most likely I will be doing a light weathering based on your explanations (I learn from you a lot) but I am not ready for the major stuff like hairspray and chipping fluids. Thanks for following my project, it means a lot coming from you. Yves

Beautiful work. Great idea for the stands. Yves

Amazing of beauty, precision and realism. You are a Master with PE and plastic kits. Yves

My first attempt at oil canning. I am trying to learn from the experts but this is a big hull and sometimes my fingers cramp on that dual action airbrush. Plus it is 94 outside and besides drying the paint, it does not help me: If it is too bad, a coat of primer and we are back to Square 1. Yves

Working on the stern and installing rudders and diving planes supports: Yves

The pine will likely warp. Not sure about Premium quality, but I am done with those pine boards from Lowe's or Home Depot. You will have to treat it (varnish) to minimize the risks. YVes

Great effects with the LEDs. Glad you went with warm white/yellowish color. Yves

A few more technical information related to the stern of the vessel. First, the rudders mechanism, well rendered by Trumpeter: Then the Rear Diving planes. This one is non existent with the Trumpeter kit, unfortunately. Finally, the rear torpedo door geometry, which is missing completely on the Trumpeter kit but corrected with the RCSUBs torpedo doors addition: Yves

A few pictures and information. The finished pressure roof for the rear torpedoes compartment. My attempts at replicating a rusty exhaust system pale in comparison to what some experts are doing (i.e. RGL). Basically, this is an exhaust painted fully with rust color and then loosely sprayed from a far distance with a black spray can. Not perfect, but it will do.... The (almost finished) module. You can see the work on the main bulkhead to allow the passage of the starboard exhaust. Inserted in the hull: Yes, what you see on the outside of the hull, is actually the exhaust for the diesel engine, after going through the muffler: Another view: The rear torpedo door (still needs some adjustments): The trumpeter kit proposes some kinds of plates to hide "the absence of details" on the pressure hull. My approach is to try to replicate as much as possible of whatever may be visible and offer it for the discerning enthusiast: Finally, the rudders: The barnacle/pitted effect is simply done by spreading Tamiya glue on the surface and taping it with a hard tooth brush. It creates a large quantity of small impacts that simulate to a certain extent, the barnacles, foundry defects and overall wear of the machine. At this stage, you may think that this module is finished. Not really. I still need to work on the transmission clutches and the shaft locks, that Trumpeter skipped (again) as they did for a lot of details. Yves

Since we are talking about storage, I am trying add a few details to the outside of the pressure hull. As you can see from the drawing below, the top of the pressure hull has that large torpedo storage container, two pressure tanks for the ballasts and the two exhaust systems for the diesel engines: I am trying to place all this equipment on the existing compartment, by reworking the bulkheads and using some spare parts from the second set of parts. All this, while keeping in mind that this compartment may be installed permanently in the hull. I am still debating. The hatch for loading the torpedoes inside the rear compartment has been totally skipped by "the Trumpeter". I could do it, since I have a spare hatch (you can see that on the right of the drawing "achieres Torpedo"), but it would involve too much butchery of the existing compartment and would conflict with existing parts. Besides, it will not be visible at all. Compromises....as always. Yves

Same torpedoes front and back. Only three direct shots from the stern (2 under the flooring, and one in the tube. Plus an additional one in the storage outside of the pressure hull. You had to surface to get to it. Not an easy job. Yves

I would go with B. Plus spread generously fish oil and other repulsing fish guts on top of it. Yves

While fitting the compartment into the hull, I realized that Trumpeter made a mistake: the length of the rear torpedo tube is too short ! They molded all the parts (front and rear) in the same way, and the rear is too short of 1.4 cm. Thus, using the spare parts I have, I extended the tube accordingly. I tell you, they are consuming way too much rice alcohol, over there.... Yves

Why not use the clay bar used for automotive detailing. You will have to use it wet, though.... Yves

A couple more details: The paper/plans holder is one of the rare Trumpeter parts made of photo-etched brass. It is of excellent quality and very well designed. It si truly regrettable that Trumpeter did not provide more internal PE details to improve the level of accuracy of that large model. From RCSUBs, the rear torpedo outer door has been installed. I also added a brass rod (interrupted) for the door command as well as two toothpicks for the diving planes controls. Those will only be visible for an inch or so through the opening on the starboard hull and thus, there was no reason to extend them. Besides, their extensions would have prevented the insertion of the module in the hull. Yves

I like the planking in the center approach. However, you will not be able to install any guns, with this method. You could also try planking in a less geometric way, and have it only where you need it to support a gun or a specific part of the deck. Yves

Beautiful model. And you are moving rather fast.... Yves

Some pictures of the rear compartment. First, I had to take care of the stringer located in the rear. Because of the support I installed with the brass deck and cutout plastic deck, the stringer did not fit. The part provided by Trumpeter is not prototypical no matter what, and thus it does not make too much of an impact to modify it. It is invisible anyway: The picture shows the original part. Because of the realistic pressure hull end, it has to be modified to follow the convex shape. The original submersible had four stringers on the stern, as shown in the following pictures: Finally, some shots of the almost finished rear compartment. It is by far the most complicated to assemble, with the propeller shafts, rudder commands and the extremely tight fit of that compartment in the stern. I still have to glue the torpedo outside door and install a rod for the control. I hope you like it. Yves

Really impressive. Yves

So, before showing you the finished rear torpedo compartment (I still have a few details to take care of), let's share some information about the intricacies and technical details of that section of the boat. My goal, again, is not only to show you the implementation of that great kit, but also to learn about these incredible vessels and their technical solutions. The picture above shows the two electrical motors/generators used to propel the submersible, when under water. It also shows the two large electrical panels allowing the control of the motors/generators. Switching is done by maneuvering the large wheels. From the "Manual": 1) E motors. The E motors working as electric motors drive the propellers and working as a generators charge the batteries. They are fan cooled, encapsulated, direct current, double armature, with compound windings and commutating poles. The motor is built from two parts, casing with installed windings, which are bolted together. There are also two armatures installed on the same shaft inside. In the upper parts of casings are cold air inlets and warm air outlets. Bottom parts up to the bottom edge of the shaft are water resistant and at the lowest points draining cocks are provided. Each double armature motor has 2 x 8 main poles and the same amount of commutating poles. All poles are bolted to the inner side of the rotating yoke. The shaft has installed two armatures and runs in two slide oil ring lubricated bearings. The bearing on the diesel engine side is built as a thrust bearing for absorption undesirable thrust. The bearings of the E motors are cooled by sea water. During surfaced drive the cooling system is fed by the diesel engine cooling pump and while submerged, by the cooling pump. A fan blower is attached to the casing. It draws fresh air from the E motor room and blows from above into the both parts of the motor. The warm air escapes through outlets in the upper parts of bearing casings and is directed to air coolers, which are installed between the E motors. 3) Main switchboards. b) Main switchboards with Rotary Switches Type VIIC U-boats are equipped with main switchboards with rotary switches provided by A.E.G. Company, Berlin. The stb. main switchboard is connected through the aft battery automatic circuit breaker to the aft battery, the port main battery switchboard is connected through the forward battery automatic circuit breaker to the forward battery. Each battery automatic circuit breaker has following settings: overload current of 6000 A in 10 seconds short circuit current of 12000 A The main switchboards are built from iron framework, which supports switches, control and measurement equipment necessary for driving and charging. The order of the switches on each switchboard from left to right for both E motors is as follows: 1 Main battery switch with charging connection below 1 Starting relay with with indicator lamp 1 Field switch 2 1 Drive direction switch 1 Field switch 1 with indicator lamp 1 Motor - series-parallel - switch 1 Battery - parallel-serial - switch Above the switches are installed the fan blower motor switch, board illumination switch, silent running drive switch, and measurement devices. The speed controller is installed on the right side of each switchboard. Timed relay and auxiliary relay are installed below the measurement devices and above the drive direction switch. Main battery switch is two-pole. When switched on, the battery automatic circuit breaker is connected with main switchboard. The switch is operated by an isolated handwheel. By rotating the handwheel to the right, the switch turns on, rotating to the left turns the switch off. In the bottom part are charging terminals, accessible through flap on the casing. Drive direction switch is five-pole and is used to toggle the current direction in the armatures to change motors direction of rotation. By turning the handwheel to the right, the motor runs forward, by turning to the left, the motor runs backward. The switch is turned off when the handwheel is the middle position. The drive direction switch is interlocked with the motor field switch so that the E motor cannot be turned on, when the field switch is turned off. Motor - series-parallel - switch is a four-pole toggle switch. Turning the handwheel to the right, causes the armatures to be connected in series and the equalizer line is disconnected. When the handwheel is turned to the left, the armatures are connected in parallel and the equalizer line is connected. By means of auxiliary contacts the circuits of the timed relay and silent running drive switch are closed. Battery - parallel-serial - switch is a double three-pole toggle switch. Turning the handwheel to the right, causes parallel connection of the batteries. When the handwheel is turned to the left, the batteries are connected in series. By means of auxiliary contacts the circuits of the timed relay and silent running drive switch are closed. Starting relay is a two-pole circuit breaker. It normally works fully automatically, but in case of damage, it also can be manually operated. This contactor limits too high starting current. Immediately after turning on all switches or after expiration of the adjustable (to 1 second) timeout the contactor opens and in its off-state connects the starting resistor into the E motor armatures circuit. When the contactor contacts close (the current has gone down, the voltage is low), the starting resistor is short-circuited. When the main current circuit opens, i.e. by turning off any of maneuver switches, the starting relay is opened and the starting resistor is connected. When the relay is damaged, the starting resistor can be short-circuited manually. In that case before setting the maneuver switches, the starting relay must be turned off. When starting relay is activated, the indicator lamp lights up. Using the motor - series-parallel - switch and battery - parallel-serial - switch three drive speed ranges corresponding three voltage ranges can be set (see E-Sketchbook). 1. Batteries in parallel, armatures in series 2. Batteries in parallel, armatures in parallel 3. Batteries in series, armatures in parallel Within these three ranges, further adjustments can be done by changing the current in shunt windings using the double motor field rheostat – the speed controller. It also can be used to control the output voltage of the E motor while charging the battery. Each single rheostat is connected in series with single shunt winding of the double-armature machine, then they are connected in parallel with each other. This rather complicated description gives us a feel for what it took to operate these complex machines. Needless to say, the importance of capable mechanics was paramount on these vessels, as everything was done by hand and following a very precise procedure. This drawing shows the cooling system used to keep the electric motors/generators at operating temperatures. As indicated in the Manual, the primary cooling pump is located in the Diesel/engine room (bottom right on the drawing) and distributes cold salted water to the Starboard compressor and the two electric propulsion motors and fans. Definitely a plumber's dream.... or nightmare. The rear compartment similar to the front torpedo compartment, is equipped with a torpedo storage between the pressure hull and the outer casing: These two pressure proof containers are marked in red on the drawing. Internally, the rear bulkhead near the torpedo tube is equipped with an electric compressor on the port side and a diesel compressor made by Junkers, on the starboard side. These compressors are resting on top of the torpedo compensation tanks: The picture above shows the U-995 (only surviving Type-VIIc) which has been heavily modified and is not really representative of what an early Type VIIc was, during the war. Most likely, dual electric compressors were the norm before the Germans realized that due to extreme electrical consumption, they had to swap one of them with a diesel powered Junkers unit. The Trumpeter kit (with its short-cuts) just ignores that part of the compartment and does not offer any starboard compensation tank and no Junkers compressor. Yves

This is spectacular and with this kit, you are finally allowing non-experts modelers to build Period Ships in the proper way. What are the woods being used in the kit? You also mentioned a price of about $350 for the kit in another thread. Will the frame used to build the ship, be included in the kit? Yves

Trying to finish the rear compartment. It is by far the most difficult to realize and set in location. One of the reasons is that I am trying to make it more complicated than it was designed for. The second reason is that I am trying to power the shafts and allow the propellers to rotate. Finally, the capability to take apart and insert the starboard half-hull makes all the assembly very tight and delicate. A lot fo sanding has to take place to allow the insertion of the half-hull in the main hull. I think that once I put together the entire rear compartment, I am going to glue it (with just a couple of points) to the main hull and get the shafts coupled permanently. It is necessary to file the main bulwark to allow the insertion of the cover-hull: Lots of complexity for not much additional results. We will see how this goes. Yves

Part E of that long deck: We are soon running out of PE parts....which is a good feeling. One more section to go.... But it will wait, as there are far too many delicate parts to glue on it. Yves

Little progress, reconstructing: Yves

Beautiful, simply beautiful. Yves