1/144 U-Boat Type VIIC/41 KNM Kya (ex-U-926)

[He Who Shall Not Be Named]

Well, simply put, I'm not aware about anybody who knows so much about this hobby that has spent so much time to divulgate his knowledge. And Cabal reports are all a novice can ask.
I've got some progress to report: finished piston unit complete with endpoint microswitches and pushrod seals installed. Mocked up components with bluetack to represent the possible layout.
Still, I'd like to find a cheap, small reversible ESC to use instead of those pesky servo boards.
I've eyed those two items:

http://www.mikroantriebe.de/download/er500_a.pdf

http://www.autorc.ro/module-electronice/1396-variator-mini-thor-12v.html

And this conversion project as well:

http://www.wettringer-modellbauforum.de/forum/index.php?page=Thread&threadID=34803

What would you choose?

http://www.sub-driver.com/electronics/speed-controllers-and-motors/nano-speed-controller.html

[Von Hilde]

I have checked out the s307, and it seems to have several tower mods over the course of its carrear. Basiclly the type VII tower with and without wintergarden and the fairing configguration.this was in 1960 before being scrapped in 64. Original Wintergarden and perriscope placement. In the 1959drawings theres is a discrepancy with the obs scope. In the drawing of the tower with the wintergarden removed the fwd scope is not in the correct place, as the picture was only a suggestion of the tower design and never used. Also note the schnorkle layout is complex array of induction and exhaust ducting. The Norwegan designer was trying to sell his design to the royal navy to get the contract to upgrade a 1939 u boat. Project would have cost Norway a ton of money for a boat thay would scrap in 5 years. They built a new Kya instead, with the money.

[zhuravlik]

So, basically, you are saying that Kya was never received her sail? But this contraddicts Eberhard Rossler: "Using the reshaped bridge style of the Walter U-boats, instead of the usual VIIC bridge (minus "wintergarden", the AA platform behind the bridge, and armament), only an insignificant increase in speed (38 revolutions per knot as opposed to 40 revolutions per knot) resulted, but the depth keeping properties were greatly improved".
The U-Boat, page 160
And that means the boat was modified and tested.

[Von Hilde]

So, basically, you are saying that Kya was never received her sail? But this contraddicts Eberhard Rossler: "Using the reshaped bridge style of the Walter U-boats, instead of the usual VIIC bridge (minus "wintergarden", the AA platform behind the bridge, and armament), only an insignificant increase in speed (38 revolutions per knot as opposed to 40 revolutions per knot) resulted, but the depth keeping properties were greatly improved".
The U-Boat, page 160
And that means the boat was modified and tested.

I only know that the picture of the boat U 926 at the surrender was a standard Term-1 tower with the 2cm flak 38 and winter garden. The pictures taken of the Kya in 1960 had the original Term without the gun mount. Somewhere, I have seen a photo of the tower with the platform and dish removed. and the gyros compas housing off. This tower had two port holes forward in the center like the 1959 drawing and it had a closed in after section and an overhead. It had the obs scope in the cowling front, and attack scope aft in the original type VII positions. If the attack scope was where it is in the 59 drawing, it would go down thru the outside of the main controll room's wtc. If not then too close to the bulkhead for a man to get between to look aft. The scope's well for it, would go into the fuel bunker below the radio room deck, also. Old Photographs from the Royal Norwegan Navy would be wonderful. You would think if it was successful they wouldnt have converted it back and put in service then scrapped, a few years laterU 570 type VIIC Turm IKya streamlined for tests you can bairly make out the weld seams where they added the cover aft. I wish there was a better picture, but it appears they just covered the bridge and cut some view ports for the watch. The open bridge definately kept down the speed submerged. And the closed bridge is much quicker as the US found out on the early fleet boats. That mod is similar to the "Atlantic" sails on the post war fleet boats. Im not so sure about antenna and schnorkle placement, since you cant see the other side where it would connect

[zhuravlik]

For what i've understood, Kya went at demolition yard with her streamlined sail. It would not have had sense at all to re-install a conning tower!
I could build the original term conning tower but i love that GUPPY-esque look it has.
Yes, photos from http://forsvaretsmuseer.no/ would be nice... Submitted a request but no avail.
I still search for relevant pics and i still find something useful but i'm not holding my breath waiting to find the perfect reference photo. After all i'm not in the rivet counter league by any means.
Also, I've selected the microantriebe ESC: it's the smallest i can find and is used by this very respectable gentleman:

http://www.mikromodellbauwelt.de/html/modelluboote.html

Recently i had some shopping: bought a Hobby Boss 1/350 Typhoon and a Yasen, same brand same scale, a 1/350 Airfix Trafalgar and a much wanted Special Navy Type XXIII.
Well, the little Yasen can hide in its belly a 20 cm lenght of 3,2cm tubing... Guess who will be the next?

[zhuravlik]

Ah Von Hilde, that Kya photo is a quick photoshop job of mine! I just modified the sail from that pic i posted in P.Calvi's thread wich represents KNM Utvaer (S303)...

[Von Hilde]

Ah Von Hilde, that Kya photo is a quick photoshop job of mine! I just modified the sail from that pic i posted in P.Calvi's thread wich represents KNM Utvaer (S303)...

Verry well sir, carry on. Your doing a fine job with that. Not many of us like to take a model out of the box and modify it to be a unique representation. I have as much satisfaction researching, the subject, as I do trying to engineer the the building of the project.

[zhuravlik]

Thanks, Von Hilde, for your kind words. They inspired me to start again with this conversion project.
I've found another photo of Kya's sail after her conversion: A round porthole can be seen in what i believe is the front end of the sail.
Having abandoned the idea to use the piston as a moving forward bulkhead, now i'm investigating the possibility to extend the bow part of WTC with a 4,3mm long, 2cm diameter of electrical plumbing to house the threaded rod/microswitches assy. It can be done.
Other critical areas are: the rudder linkages and direct drive couplings.

[zhuravlik]

Looking for infos about balkon gerat shape i've stumbled upon another forum (some serious rivet counters there...!)
Well, a member found my photoshopped picture and called me an idiot for faking it. :)
But the great piece of news is that i can explain that recess pictured in the photo above: Kya retained her original snorkel mast after the conversion!
I've registered myself in this forum but my account in still waiting admin

[MFR1964]

That's a picture i posted long time ago, it's the U 995, they removed it during "the restauration", not good!!!<br />
My type VII has a Balkongerat at the bow, a type IX has it at the beginning of the front keel.<br />
Not much pictures from that device, i have a couple, have to look for them.<br />
<br />
Manfred.

[zhuravlik]

Hi Manfred,
I would be glad to see those photos. How would you build this dome?
I fear that renshape would be too buoyant and I need to keep inertias low on the yaw axis, those itty bitty rudders, you know..
Maybe with lost foam?

Meanwhile my account was accepted but the downloaded photos appear to be corrupted somehow (getting "bogus dqt index 10 error"

[zhuravlik]

Nuntio vobis, magno cum gaudio:
Habemus photographia!

Mr. Tore was so kind to promptly respond to my call.
He posted a couple of pictures taken from this very thread and a true gem!

[MFR1964]

This was the start of my balkon gerat for my 1/35 scale type VII.



I was lucky to have this, the Original shape from a good friend, i fear you have to make one on your own, the shape is not that complicated, this one is made from wood.



Placing all hydrophone sensors.



Placed at the bow of my type VII.



The balkon gerat placed at a type IX.



Another shot of the balkongerat at the bow of the U 995.

Manfred.

[MFR1964]

I forgot to mention that my balkongerat is hollow, builded it up with some layers glasscloth with epoxy<br />
<br />
Manfred.

[zhuravlik]

Thank you so much, dear Manfred, those photos are very appreciated.
I plan to build balcongerat using lost foam method, I guess three layers of 50g/sqm FG will suffice.