Author Topic: Rear torpedo section VII / 3D model / 1/72 (Read 32480 times)

Marko · « **on:** 15 Apr , 2012, 17:48 »

hello guys,

i thought it would be wise to split the design into separate topics, to keep the topics more clear. The printing is not yet possible, so i decided to start the rear section with the current standards anyways. currently i am awaiting those big sets of plans from Fritz K

Marko · « **Reply #1 on:** 16 Apr , 2012, 14:25 »

The design proved to be almost correct, here are the results in photos:
the only thing which bothers me, are those three vent holes located on the rear portion of the fuel tank, i have to implement the tanks curvature into it to prevent seein into the pressure hull through those three holes, so back to the board correct that fiddly bit.

TopherVIIC · « **Reply #2 on:** 16 Apr , 2012, 18:19 »

Marko -
Once more you have a start - and a start is a good thing!
Keep in mind that the aft section, like the forward torpedo section, is actually a couple of tapering conical sections. Picture being inside a cone that is getting smaller as it goes aft. Developing 2-d planar surfaces and rolling them into 3-d physical models will take a little bit of work.
On the drawings, where you see the German word "Knick" it means "Kink" - it is where planar forms are welded together to make offset frustums - cones with their heads whacked off, and axis shifted.
If you are building from the "E-Machine" bulkhead, back, you are dealing with three separate conical sections. Not one of the ceilings will be at 90 degrees like a regular room would have.
In this section, because of the small tapering diameter of the aft conical sections, the internal ribs (DruckSpant) are not all at the normal 600mm spacing. Look closely at the drawing and you will see what I mean.
Also keep in mind that the torpedo compensating tanks in the extreme aft section actually surround the walking space of the working deck (floor) and there was narrow space for a single torpedo stowage belowdeck.
I look forward to seeing what you come up with - and I hope this helps a bit...

Simon's drawings, and this http://www.kubische-panoramen.de/index.php?id_id=5375&p=i are also great!

Christopher

Marko · « **Reply #3 on:** 17 Apr , 2012, 01:43 »

Yep,

the thing that makes the shapes complicated here is the molding from revell, i tried several combinations of surface creating, and current variant is the closest i can get. Since the revell molded the hull insides as continuous piece (no tapering, i cant do much about it, except of thinning the hull halves, which i would like to avoid as much as possible.

My first attempt was making design directly as per drawings, but i could not get the prototype to fit, too much gaps. The current model fits in 95%, yet i still have to work on it, as mentioned the three flood holes just above the fuel tank are mostly problematic, however this morning i got an idea how to solve it, and will try it as soon as i get home from work. Though bear in mind that this paper model is just prototype with basic shapes, to get the basic outlines of the design area. I will probably make the section virtually elongated into rear with the partial torpedo tube and components near it half sticking out of the rear bulkhead, then it will be added final solid model of the rear segment of pressure hull, just to get the impression through the flood gates that the hull actually continues. I hope this will be acceptable substitution, since i really would not like to whack up the whole hull up due to esthetics, and also gaps would be difficult to fill in this case.

Marko · « **Reply #4 on:** 18 Apr , 2012, 13:26 »

hello guys,

finally i made it through the last test, and i think i finally nailed it, even better than i expected.
here is the result in photos:

Here is a final version (i think it was Nr. 11) that i unrolled and assembled with paper. The differences between this and the previous variant are in elongated arc of the ceiling to follow the contour of the cut-out in the hull, and the curve that fills in the saddle tank gap from the inside. This way i achieved the effect of continuous pressure hull when seeing in from the three saddle tank flood gates. Also the red lines are guide lines for the PH virtual extension which will be made as solid piece to trick the eye when seeing inside from the rear under flood gates.

Marko

Marko · « **Reply #5 on:** 19 Apr , 2012, 11:04 »

hello,

i have a question, had a spare torpedo in rear torp. room a cylindrical or other type container, or was it only laid in a cradle beneath the torp. room floor?

TopherVIIC · « **Reply #6 on:** 19 Apr , 2012, 12:56 »

Marko -
It seems to me that a container in the extremely confined aft torpedo room/E-machine space would be extremely unwieldy. A solid tube like the ones stowed below the top decks would not work - no room. A nested container would either have to be hinged the entire length of the container on two sides, or it would have to be a lift off affair. Both cases would involve handling large, ungainly useless pieces of hardware afterwards, all of which would take up more room than would be available. It would also add dead weight that would serve little function.

The drawings I have seen of the forward torp stowage, and photographs show cradles, chocks, and straps, with flimsy deck support to keep the working deck level. I assume the aft torp stowage would be similar.
Just my thoughts - but a good question to ask.
Christopher

Marko · « **Reply #7 on:** 19 Apr , 2012, 17:00 »

Quote from: TopherVIIC on 19 Apr , 2012, 12:56

It seems to me that a container in the extremely confined aft torpedo room/E-machine space would be extremely unwieldy. A solid tube like the ones stowed below the top decks would not work - no room. A

The drawings I have seen of the forward torp stowage, and photographs show cradles, chocks, and straps, with flimsy deck support to keep the working deck level. I assume the aft torp stowage would be similar.

so was my opinion. well, i did not bother drawing it yet, however i made the floor using drawings that i have + quite a bit recalculations to get proper measures for the 1/72 scale. Im calling it for a day.

Marko · « **Reply #8 on:** 22 Apr , 2012, 14:23 »

hello guys,

well it does not look much progress, but i completed the walls of the compartment, and i finally have inner perimeter where i can draw the interior parts. Also i made the false PH elongation, as seen on the picture:

Marko · « **Reply #9 on:** 28 Apr , 2012, 05:25 »

took some while, but here is some progress, though still a lot of work on it has to be done

this time i am working on it bottom side up, have to complete the torpedo holder and then to the upper section. Feel free to comment it and if i made something wrong, point the issue out and i will try to solve it :-)

tore · « **Reply #10 on:** 28 Apr , 2012, 08:40 »

Marko
In this area is situated an important part of the submarine which you should try to incoporate, the thrustbearings, which transfer all the power from the propellors to the hull. As such the thrustbearings are mounted on a very strong structure intergrated in the pressurehull. I have posted a picture below indicating the arrangement.
Tore

Marko · « **Reply #11 on:** 28 Apr , 2012, 09:35 »

aha, i noticed those already, and made appropriate holes in the "catwalk" floor - "T" shaped cut out in the floor:

although i am not sure how, or if should i replicate the foundations on the starboard side (cut-out) side of the hull, maybe should i do the foundation only on the port side?

tore · « **Reply #12 on:** 28 Apr , 2012, 09:51 »

Marko
I don`t know how you are planning the propellorshafts which of course is an intergrated part of the thrustbearing, I guess that would be guiding you how to draw the thrustbearing and foundation. Below is a photo of typical thrustbearing housing ( not 100% VIIC, but will do).
Tore

Marko · « **Reply #13 on:** 28 Apr , 2012, 14:53 »

well, another dilemma:
after ribbing has been done, the torpedo intersected with it. currently i made a cradle like form into the ribs, so the torpedo head is laid into the hull on front end too. The only possible way is to shorten the torpedo by 1 good cm, maybe a little bit more. By doing this, this torpedo would be shorter than the others from CMK. im not sure what to do.. i cant lift the torpedo compartment floor since it would have to be lifted for good 3-4 mm which would increase the floor height difference between engine section and torp. room, and i cant afford that drastic change here.. So, should i shorten the torpedo or leave it as is?

tore · « **Reply #14 on:** 29 Apr , 2012, 00:08 »

Marko
It looks to me the your torpedofront is a little too butt compared to the posted drawing below. May be if you make the shape as on the original drawing it will fit in.
Tore

Marko · « **Reply #15 on:** 29 Apr , 2012, 06:20 »

hm, were the torpedos so tapered? Well, i did not intend to print out a new torpedo, since i've redrawn it using CMK's torpedo as a template, since i would prefer using that one instead of printing new one, or maybe should i whack the original torpedo off a bit to fit it in? i could make it virtually elongated in the rear where the "box" in the bulkhead is, and i think i will do exactly that, ill post a picture as soon as ill finish it.

tore · « **Reply #16 on:** 29 Apr , 2012, 08:29 »

Marko
I would rather focus on the propellorshafts, thrustblocks,tailclutches and E-motors than a sparetorpedo if I had to make a choice, but I`m an engineer and not a torpedoman.
Tore

Marko · « **Reply #17 on:** 29 Apr , 2012, 08:38 »

hmm, ok,
this is around 3rd attempt, and now it looks like this:
i tapered it a little bit, i checked the CMK's torpedoes, and its true, they are a bit tapered more than i designed it, yet not so much as mine, but i will probably give one into printing in this case. Now it does not intersect the hull anymore, i also trimmed it down little bit, 4mm to be exact, however it does not show much of a difference after it will be partially hidden behind E-motor and its electronics. Tore, you marked that the forward cradle that i made, that there actually is no cradle, but how in the world did they support it? there was a cradle with straps behind the torpedo cetre of gravity, but the front down force would be too high i guess, so it had to be something else supporting it in front, at least top of the vertical rib, (without the cradle that i made in front). Any opinions on this issue?

tore · « **Reply #18 on:** 29 Apr , 2012, 09:26 »

Marko
I think you got mixed up with the strong thrustbearingstructure which is way out overdimensioned for a torpedocraddle. It could very well be that there is a craddle beween the two structures. It migth also be that the two foundations which you indicates as torpedo craddles in the E-motor area are the two foundations for the E- motor and that it could be one (not two) craddles beween the two E-motors.
Tore

tore · « **Reply #19 on:** 29 Apr , 2012, 11:37 »

Marko
May be the the below picture explains better the foundation leg of the E-motors
Tore

Marko · « **Reply #20 on:** 29 Apr , 2012, 11:57 »

cheers Tore, thanks for the heads up, well, i am looking on my example of plans, and looks like that the E motors are cradled on two points (same solid mount) on the side to the pressure hull with foundation and probably on the same spots on the bottom as your cross section shows.

tore · « **Reply #21 on:** 29 Apr , 2012, 13:30 »

I guess you are rigth. Well Marko you have a lot to acommodate in this compartment, on the picture below I have indicated a few essentials. Take your pick, quite a task I dare say.
Tore

Marko · « **Reply #22 on:** 29 Apr , 2012, 13:51 »

Yep, it will be a lot of work, a lot more than i anticipated. Especially beneath the floor. Here is my interpretation of the e motor bottom foundation with its mount. I guess will go for the side mounts and side foundations next. Note, on the starboard side i will be showing only motor mounts, without the foundations, so they wont obscure the interior much, after all they a re more or less just solid boxes with smoothed edges. To accommodate bearings in rear and in front of the E-motors i will have to shorten these for 1 or 2mm on each side

tore · « **Reply #23 on:** 29 Apr , 2012, 14:53 »

Interesting view. You have a very thick centerplate in the middle of the foundation structure. I believe the strength is from the boxshape rather than the plate thickness as I have indicated below
Tore.

Marko · « **Reply #24 on:** 30 Apr , 2012, 05:08 »

you a right on this one, but i rather made it like a thick centreplate, since i am making a cut out, and therefore i cant extend it out much. I could later split the middle box foundation, but that just would not look right, CMK did the same thing at the engine section, so technically if i make it to box i will ruin the continuallity of the foundation, so i guess id rather leave it as is

here is link to the CMK's engine compartment, located on AMP site to compare:
http://www.rokket.biz/models/modelsweb/rokket/u557/images/tcumm_eng.jpg

erm, where did the shaft diameter change? as i am now making the clutch, i am assuming that diameter got narrowed there? diesel engine shaft - EM shaft - clutch - shaft diameter reduction. Or was it any other way? Could it be that shat diameter was constant? If it was, then we have a problem since CMK made the diameter 5mm, and revells exit diameter is only roughly 2,5mm maybe 3mm at propeller.

Marko · « **Reply #25 on:** 30 Apr , 2012, 08:54 »

i made foundations, but looks like those wont be much visible after assembly, maybe just bits and pieces of them:

tore · « **Reply #26 on:** 30 Apr , 2012, 11:40 »

Quote from: Marko on 30 Apr , 2012, 05:08

you a right on this one, but i rather made it like a thick centreplate, since i am making a cut out, and therefore i cant extend it out much. I could later split the middle box foundation, but that just would not look right, CMK did the same thing at the engine section, so technically if i make it to box i will ruin the continuallity of the foundation, so i guess id rather leave it as is

here is link to the CMK's engine compartment, located on AMP site to compare:
http://www.rokket.biz/models/modelsweb/rokket/u557/images/tcumm_eng.jpg

erm, where did the shaft diameter change? as i am now making the clutch, i am assuming that diameter got narrowed there? diesel engine shaft - EM shaft - clutch - shaft diameter reduction. Or was it any other way? Could it be that shat diameter was constant? If it was, then we have a problem since CMK made the diameter 5mm, and revells exit diameter is only roughly 2,5mm maybe 3mm at propeller.

Marko
I am posting a sketch showing the shaftarrangement with all the components. I have marked red where I believe the shaftdiameter was increased.
Tore

tore · « **Reply #27 on:** 30 Apr , 2012, 12:19 »

Marko
May be it`s an idea to explain the purpose of the various shaft components. Engineclutch : to disengage dieselengine from propellor and E-motor fi. when running on E motor. Bulkhead shaft stuffingbox: to make watertigth (not pressure tigth) compartment bulkhead between E-room/Dieselengineroom. E- motor: actually two motors in one and operating both as a motor ( maneuvring and propulsion) and generator ( battericharging). Tailclutch: disengaging propellor fi. when charging batteries alongside.
Thrustbearing: to transfer load from propellor to the hull ( can take up to 10 tonnes of thrust). Removeable propellorshaft flange: to be able to pull the propellorshaft through the sterntube for maintenance. Propellorshaft brake: to prevent the shaft from turning (idling) when disconnected. Is able to take the full idlingload when the other propellor has max load from the dieselengine. Sterntube packingbox: to prevent waterleakage along the propshaft at max divingdepth as well as at depthchargeattacks.
Tore

tore · « **Reply #28 on:** 30 Apr , 2012, 14:05 »

marko
Studying your bulkhead shaftseal between engineroom and e-room it seem to be on the big side. Check with one of the GE plans and you`ll get the proporsions.
Tore

Marko · « **Reply #29 on:** 30 Apr , 2012, 17:42 »

I know i know, Tore that is the old drawing with thinner shaft diameter

Maybe that is still too big, but i have to merge it with CMK's design.

tore · « **Reply #30 on:** 30 Apr , 2012, 23:57 »

Marko
Then I guess it remains only a few details on the shaft inside the E-room which I indicated on the posted drawing.
Tore

tore · « **Reply #31 on:** 01 May , 2012, 00:33 »

To get you an idea how it looks like I have posted a sketch showing the principle ,not accurate details for a VIIC, but I guess it do.
Tore

tore · « **Reply #32 on:** 01 May , 2012, 08:01 »

Shaftdiameter.
Futher to my post of the above. The tailshaft beeing 175 mm diam has a shrunk on liner in the area of the sterntube total extern shaftdiameter is then 195 mm.
Outside the pressurehull in the area of the A bracket the shaftdiameter is 180 mm having a liner making the external diameter 220 mm. Outside the pressurehull, the exposed part of the shaft between the A bracket and sterntube is wrapped with wire and canvas.
Tore

Marko · « **Reply #33 on:** 01 May , 2012, 17:07 »

Erm, did have shaft flange any foundation perhaps?

over here shows as the brake was basically integrated with foundation:
http://models.rokket.biz/index.php?action=dlattach;topic=940.0;attach=2509;image

any idea how should i make this? perhaps just a simple foundation as i did to the clutch, only less massive?

tore · « **Reply #34 on:** 01 May , 2012, 23:27 »

Marko
The flange as such has not any foundation ( it`s rotating). The brake is simply a band working on a shaftdrum immediately aft of the flange. The band is tigthened by a detachtable lever handoperating a rachet. There is of course a small foundation on the fixingpoint for the ratchet. I thing I have a picture some place and shall post it if I find it. It is really not a very sofisticated design.
Tore

SnakeDoc · « **Reply #35 on:** 02 May , 2012, 03:32 »

Hi Guys

Quote from: tore on 01 May , 2012, 08:01

Shaftdiameter.

Futher to my post of the above. The tailshaft beeing 175 mm diam has a shrunk on liner in the area of the sterntube total extern shaftdiameter is then 195 mm.
Outside the pressurehull in the area of the A bracket the shaftdiameter is 180 mm having a liner making the external diameter 220 mm. Outside the pressurehull, the exposed part of the shaft between the A bracket and sterntube is wrapped with wire and canvas.

I've got also few values:
Main thrust bearing total length: 690 mm
total width: 640 mm
total height: 857 mm
A bracket (Wellenbocklager) diameter: 200 mm
length: 595 mm
Stern tube (Stevenrohre) length: 6710 mm
diamter: 200 mm
Length of the propeller shaft (between the propeller and the flange): 8010 mm
Length of the thrust shaft (between the flange and tail clutch): 1405 mm
Length of the electric motor shaft (between the tail clutch and diesel engine clutch): 4025 mm
Break drum diameter: 400 mm
width: 55 mm

--
Regards
Maciek

tore · « **Reply #36 on:** 02 May , 2012, 13:32 »

Marko
The photo I thougth I had wasn`t any good so I`m posting a new systemsketch this time for a XXI type boat but I believe the system is about the same. Anyhow you see the small foundation of the brake.
Tore

SnakeDoc · « **Reply #37 on:** 02 May , 2012, 14:28 »

Hi

Quote from: tore on 02 May , 2012, 13:32

I`m posting a new systemsketch this time for a XXI type boat but I believe the system is about the same. Anyhow you see the small foundation of the brake.

In fact, this is shafting of the type IX boats (see the 9-cylinder diesel engine).
The shaft system of the XXI is shown here:

(http://uboatarchive.net/DesignStudiesTypeIXC-S43.htm)

Anyway - for the type VII looks the same.

--
Regards
Maciek

tore · « **Reply #38 on:** 02 May , 2012, 23:04 »

Maciek
I was in doubt when I found this sketch saying it was a XXI arrangement, it looks to be too crude for such a boat, IX is more like it. As I said before I have only seen a XXI once and know practically nothing about the design. Marko, IX would make the sketch even closer to the VII apart from the 9 cylinder engine as Maciek says.
Tore

Marko · « **Reply #39 on:** 03 May , 2012, 14:39 »

hello Guys,

after taking into account all of your advices, i created this:
note, some layers have been disengaged to get the free view of the parts, brake is "incorporated" into small foundation, however i had to design a "fictional" lead-in base to the pressurehull for the sterntube, and i had to trim it, since plastic from revell would not allow this diameter to fit into hull, well, it might if i shaved it down to paper thin thickness, but i am afraid that even that would not be enough. This time i am posting a render picture, if you prefer normal drawing with meshes indicated, feel free to say it, and i will post those back again, however if you would prefer renders like these, i can make these instead.

TopherVIIC · « **Reply #40 on:** 03 May , 2012, 14:53 »

I like how your drawings are coming along! Keep Going!

tore · « **Reply #41 on:** 03 May , 2012, 23:38 »

Well, Marko, one step further, only the compressors, emergency steering, "pillenwerfer" and a few other items remains. A few remarks: the thrustbearing seems to be a little out of proporsion, it is about 30% of the mainclutch dimension. You have made a construction on the top of the thrust bearing I don`t know what it is, see picture of a mitchell thrustbearing below. As Maciek adviced the brakedrum diameter is 400 mm and the shaftdiam is 175 mm. The thrustshaft flange is forged (one piece with the thrustshaft) and has the same diameter as the corresponding removable propellorshaft flange. See picture below. Keep going!
Tore

SnakeDoc · « **Reply #42 on:** 04 May , 2012, 03:11 »

Marko
On this photo you can see the top of the thrust bearing:

--
Regards
Maciek

Marko · « **Reply #43 on:** 04 May , 2012, 06:01 »

hmm, after studying the limits, unfortunately i cannot increase brakedrum diameter since the mantle of the pressurehull will cross with it, fisrt as i have drawn it i made it bigger, but i had to scale it down so it will fit together, sorry for this one. I'd made it bigger if i could

i miss understood drawings and photos, and thought that thrustbearing has a structure on top for access or something, my bad, will get on it ASAP

Marko · « **Reply #44 on:** 04 May , 2012, 08:45 »

okay, ive redesigned the compartment floor a bit, thrustbearing got scaled down a bit, odd structure was removed, and that tiny bolt added on top (i assume that is for oiling / greasing the thing?)

with floor removed:

and with torpedo compensating tanks or trim tanks? These are a bit fictional, since i cannot make them completely round due to pressurehull mantle, or perhaps they weren't completely round?

with rounded ends )which one is more accurate?:

tore · « **Reply #45 on:** 04 May , 2012, 10:19 »

Marko
It looks better with the floor, I still think you should make the thrustshaftflange the same diameter as the tailshaft flange, they are bolted together. Se posted picture. My photo of the thrustbearing is just a general design, I see Maciek has posted a correct topview ( the picture did`t come out on my PC). Your better copy Macieks picture if you got it.
Tore

Marko · « **Reply #46 on:** 04 May , 2012, 11:13 »

hmm, if i understood right this is what you mean, if it is, is in case of render optical illusion, diameters are coincident:

tore · « **Reply #47 on:** 04 May , 2012, 12:07 »

Yes, but make the flanges a bit thicker and do away with the thrustshaftrim in front of the flange as indicated on the picture below.
Tore

Marko · « **Reply #48 on:** 04 May , 2012, 13:35 »

okay, trim has been cut away, and flange got thicker by 0.5mm (for the thickness of the thrustshaft trim (now is flange 1mm long), tailshaft trim is 2mm long, with same diameter as before = 3 mm
see render:

NZSnowman · « **Reply #49 on:** 04 May , 2012, 14:04 »

Hi guys

Here a nice close-up view of U-766 drive shaft

tore · « **Reply #50 on:** 04 May , 2012, 14:06 »

Flanges seems to be fine now, may be a line would indicate the two halfs. Somehow the thrustbearings seems to have "grown" it is sligthly too big in relation to the couplings.
Tore

tore · « **Reply #51 on:** 04 May , 2012, 14:20 »

Simon
It looks like a torsional vibration fracture. Could very well happen to a sub where you have many torsional vibration systems due to many vibration masses and different variation of shaftlength. Today it is always carried out sofisticated calculations to prevent such fractures, during the war it was not common.
Tore

Marko · « **Reply #52 on:** 04 May , 2012, 14:27 »

could i make a groove between flanges with dimensions 0.3x0.3 mm? that would be minimal dimension that printer could make, or i could leave it solid and scribe the groove with scribing tool..
edit: well, i tried to make a groove 0.3 wide, and that is essentially one third of the flange thickness, i dont see point by doing that.will rather leave it solid, and scribe it afterwards..

on to the torpedo trim tanks, are these more or less correct?

tore · « **Reply #53 on:** 04 May , 2012, 15:17 »

Do that. I don`t think the torpedo compensatingtank and the trimtank were cicular, I`m mailing a crossection at frame 6 which migth give you an idea how they looked.
Tore

Marko · « **Reply #54 on:** 05 May , 2012, 05:29 »

hm, this helps a lot, i think this could be it (marked blue in render):

by the way, on top of these tanks, should be on the port side auxiliary generator and on starboard side junkers air compressor with hose to pressure tanks, am i right on this?

tore · « **Reply #55 on:** 05 May , 2012, 06:59 »

Yes, you are entering into a fairly cramped area with a lot of stuff. On stb side is the Junker free opposed piston compressor. It is basicly a tube containing two pistons like dieselpistons meeting in the center where the combustionchamber ( and fuelinjector) is. Both pistons have on the other side a two stage compressorpiston. The unit works like a free piston four stage dieselcompressor. There are an intricate bunch of pipes like inletpipe with filter,exhaust pipe, fuelpipes, coolingwaterpipes and airpipes as you can see on the posted picture below. Make it like a horisontal tube with inlet and exhaust pipes. The airpipes from the compressor is not hoses but steeltubes ( 205 bar) connecting to a distribution chest and then HP airbottles.
Tore

Marko · « **Reply #56 on:** 05 May , 2012, 07:13 »

alrighty, thanks for the picture, unfortunately most of the piping i wont be able to do with this method, so i will have to use copper or lead wires on assembly, however main tubes i will be able to recreate, i think i could go down to 0.6, maybe even 0.5 mm diameter, which is in 1:1 then rougly 40 mm

here is the generator, i tried to match it to the one found on K

tore · « **Reply #57 on:** 05 May , 2012, 07:34 »

Seems to be OK. Below is a simplyfied drawing of the Junker compressor. It`s placed between frame 5 and 9 I believe. On port side up fwd of the E-compressor is the emergency steering as can be seen on the posted drawing.
Tore

tore · « **Reply #58 on:** 05 May , 2012, 08:03 »

Here is a picture which gives a good view of the relevant machinery, you are also able to see the emergencysteering and compensating tanks.
Tore

Marko · « **Reply #59 on:** 05 May , 2012, 09:17 »

thanks for the photo, a little bit simplified, from both sides, opinions are welcome:

TopherVIIC · « **Reply #60 on:** 05 May , 2012, 09:40 »

Marke -
This is collectively looking good Sir!
An observation I have is that I believe the diameter of the tanks you have rendered in blue is too small - the chord produced by the tank and the pressure hull should be almost like a 90 degree section facing inboard. You have the curve of the tanks smaller so they seem to curve back downward towards the pressure hull.
If you keep them in the same place more or less, but make larger diameter I think you are in business...
Christopher

tore · « **Reply #61 on:** 05 May , 2012, 10:37 »

You get quite a few cylinders into the compartment, may be you should introduce a few pipes and flanges on the Junker compressor as indicated on the picture otherwise it `s just another cylinder, and fit in the steeringgearmotor and emergency steering wheel and rods as well. Christophers remarks seems to be well founded.
Tore

Marko · « **Reply #62 on:** 05 May , 2012, 11:39 »

hmm, i could increase the diameter, but only to the cost of narrowing the floor between the two tanks. due to the torpedo tube im afraid that i could increase it only by 1 mm, so that would not help much

however, i will do some more details to the junkers compressor, especially some flanges and those fuel inlets and pumps, do you have perhaps more close up photo of those fuel pump and fuel injector piping?

tore · « **Reply #63 on:** 05 May , 2012, 12:10 »

I am posting a picture showing the Junker compressor at the testbed. The air intakefilter is as you see sligthly different. Otherwise I guess the other components are OK
Tore

tore · « **Reply #64 on:** 05 May , 2012, 12:14 »

Sorry my markings were not included so I mail another copy
Tore

Marko · « **Reply #65 on:** 05 May , 2012, 12:28 »

hm, after studying the picture, i think it could be doable to incorporate small detail with fuel injector pump and crankbox, the rest could be don only by scratch building on assembly. Will post result as soon as i make it

result, again simplified a lot, to assure solid print-out:

however, there will be other side exposed, where the cut-out is, so if you have perhaps a photo of the other side of the compressor too?

Rokket · « **Reply #66 on:** 06 May , 2012, 06:05 »

THAT is looking good!

Marko · « **Reply #67 on:** 06 May , 2012, 06:42 »

thank you Rokket

after looking the actual photos that tore provided, and some more of the museum in Laboe that i manage to snatch off the internet i created the famous emergency steering mechanism:

and here is one render image, all-in-one that has been created till now.

i still have to hollow out the pressure hull extension to save material.

And i think that we are getting slowly to the point when i will have to call it done, since i don't want it get over packed with items, since those could easily cover whole interior up

one thing that i noticed that is missing is the torpedo loading hatch, which could come in handy, since on assembly i could show torpedo loading sequence not only on the front section, but also on the rear. Has anyone perhaps some photos that show the procedure on the rear torpedo loading? (cradle, crane, or was there only a series of pulleys attached to the conning tower?

tore · « **Reply #68 on:** 06 May , 2012, 08:39 »

Marko
Sometime I guess you have to stop putting stuff in and I agree, you have the essentials, I would probably have put more in f.i steeringgear motor and drive. At your 90 degrees bend on the emergency steering rod is actually a pivot so you could stow away the wheel towaerds the pressurehull.
Tore

Marko · « **Reply #69 on:** 06 May , 2012, 11:51 »

im not sure if i understand you, could you please mark it on this render picture? should it be pivoted more towards the pressure hull? Oh, and if you have perhaps a photo of ceiling, i would be grateful, since i have to put something in there, now its so empty

oh, and can you please help me on torpedo loading hatches? Far as i know, VII/C had one spare torpedo container on top, and one regular access hatch to load the torpedoes to interior, my questions is, on this picture it is shown torpedo loading hatch, or loading to the spare torpedo container on top? right behind this access panel is another one, but a little bit shorter. I hope that model owner will not be angry with me:

tore · « **Reply #70 on:** 06 May , 2012, 13:26 »

Marko
Here are two pictures showing the emergencysteering. Of course the emergencysteering was very seldom used and one of the pictures show even the steeringwheel was stowed away by clamping it to the E compressor.
Tore

tore · « **Reply #71 on:** 06 May , 2012, 23:26 »

Marko
Sometimes you think you remember details for sure and later you realize may be it was a bit different. In a hurry I indicated the steeringrod bearing as a pivot, that`s wrong. The hingebolt is sligthly further up towards the pressurehull as indicated on the picture below, it`s simply a lid with a hole and a screwbolt with nut. On your drawing I think you shouldn`t worry too much about these details ,( it could be my memory is failing). Copy what you see on the photos rather than assumptions which migth be wrong.
Tore

tore · « **Reply #72 on:** 06 May , 2012, 23:54 »

Marko
Torpedodetails is not my table, I think Maciek is the rigth guy. We did away with the external torpedo pressurecontainers. Your are rigth it was a conventional torpedo loading hatch in the fwd part of the e-room, starting just above the bulkhead between the engineroom and e-room. On top of the picture of the emergencysteering you`ll see some of the gear used for the loading , I think pretty much the same as for the forward torpedohacth. The model you are showing seems to me as could be storing a torpedo in the external container rather than loading into the sub, but again I`m only assuming.
Tore

Marko · « **Reply #73 on:** 07 May , 2012, 00:32 »

Aha, thanks for pointing that out, well i pulled my bunch of drawings out again, and examined spare torpedo containers and loading hatches, and indeed as you said, rear torpedo hatch starts at the forward part of E-room, the component i have linked in the picture was rear torpedo container (again, you were right on that), so the panel in front of that one is actual loading compartment. I have rear spare torpedo container in resin from cmk, so i will use that one and will make loading hatch as a piece of E-room set.

I think i will also make forward spare torpedo container opened, but i think i will buy second CMK set for that and use it with Photoetched deck from modelbrass., or perhaps even scratchbuild it using plastic tube and PE deck (would save some euros)

will post results as soon as i make the hole into the pressure hull for the hatch

SnakeDoc · « **Reply #74 on:** 07 May , 2012, 02:20 »

Hi Simon

Quote from: NZSnowman on 04 May , 2012, 14:04

Here a nice close-up view of U-766 drive shaft

Where did you find this cool picture?

--
Regards
Maciek

SnakeDoc · « **Reply #75 on:** 07 May , 2012, 02:35 »

Hi Marko

Quote from: Marko on 05 May , 2012, 07:13

here is the generator, i tried to match it to the one found on K

SnakeDoc · « **Reply #76 on:** 07 May , 2012, 02:52 »

Hi Marko

Quote from: Marko on 06 May , 2012, 11:51

im not sure if i understand you, could you please mark it on this render picture? should it be pivoted more towards the pressure hull?

I think, that Tore means, that emergency steering column can be set in to position: "stowed" (as on U-995) and "operational". See the following photos (U-505 and U-889 and U-190, although type IX boats, but the principle the same):

Quote from: Marko on 06 May , 2012, 11:51

Oh, and if you have perhaps a photo of ceiling, i would be grateful, since i have to put something in there, now its so empty

Try this:
http://www.deutschland-panorama.de/museen/laboe_technisches_museum/ps/10_1051_02.php
http://www.kubische-panoramen.de/index.php?id_id=5375&p=i

--
Regards
Maciek

SnakeDoc · « **Reply #77 on:** 07 May , 2012, 02:53 »

Hi Marko

Quote from: Marko on 07 May , 2012, 00:32

Aha, thanks for pointing that out, well i pulled my bunch of drawings out again, and examined spare torpedo containers and loading hatches, and indeed as you said, rear torpedo hatch starts at the forward part of E-room, the component i have linked in the picture was rear torpedo container (again, you were right on that), so the panel in front of that one is actual loading compartment. I have rear spare torpedo container in resin from cmk, so i will use that one and will make loading hatch as a piece of E-room set.

That's right.

--
Regards
Maciek

tore · « **Reply #78 on:** 07 May , 2012, 10:21 »

Quote from: SnakeDoc on 07 May , 2012, 02:52

Hi Marko

Quote from: Marko on 06 May , 2012, 11:51
im not sure if i understand you, could you please mark it on this render picture? should it be pivoted more towards the pressure hull?

I think, that Tore means, that emergency steering column can be set in to position: "stowed" (as on U-995) and "operational". See the following photos (U-505 and U-889 and U-190, although type IX boats, but the principle the same):

Quote from: Marko on 06 May , 2012, 11:51
Oh, and if you have perhaps a photo of ceiling, i would be grateful, since i have to put something in there, now its so empty

Try this:
http://www.deutschland-panorama.de/museen/laboe_technisches_museum/ps/10_1051_02.php
http://www.kubische-panoramen.de/index.php?id_id=5375&p=i

--
Regards
Maciek

Rigth Maciek, interesting pictures you got.
Tore

tore · « **Reply #79 on:** 07 May , 2012, 10:59 »

On a drawing, which is claimed to be copied from U 570, is an aft torpedoroom plan of an early VIIC where they show two E-compressors and a separat detail cut out showing a Junker compressor, could that indicate the the first VIICs had two E-compressors?. Anyhow the Junker compressor was a wonderful machine, totally balanced, it was however susceptible to carbon deposits on the dieselside which was upsetting the delicate balance and thus required a fairly frequent maintenace.
Tore

NZSnowman · « **Reply #80 on:** 07 May , 2012, 13:36 »

Quote from: SnakeDoc on 07 May , 2012, 02:20

Hi Simon
Quote from: NZSnowman on 04 May , 2012, 14:04

Here a nice close-up view of U-766 drive shaft

Where did you find this cool picture?

--
Regards
Maciek

Sorry Maciek, I can not remember

SnakeDoc · « **Reply #81 on:** 07 May , 2012, 16:19 »

Hi Tore

Quote from: tore on 07 May , 2012, 10:59

On a drawing, which is claimed to be copied from U 570, is an aft torpedoroom plan of an early VIIC where they show two E-compressors and a separat detail cut out showing a Junker compressor, could that indicate the the first VIICs had two E-compressors?.

Interesting remark. I digged a little deeper and here are results:
The first boat equipped with the Junkers compressor was U-98. She was one of the first type VIIC boats ever. These were ordered as follows:

Yard No.	Boat No.	Ordered	Laid down	Launched	Commissioned
598	U-93	30.05.1938	09.09.1939	08.06.1940	30.07.1940
599	U-94	30.05.1938	09.09.1939	12.06.1940	10.08.1940
600	U-95	30.05.1938	16.09.1939	18.07.1940	31.08.1940
601	U-96	30.05.1938	16.09.1939	01.08.1940	14.09.1940
602	U-97	30.05.1938	27.09.1939	15.08.1940	28.09.1940
603	U-98	30.05.1938	27.09.1939	31.08.1940	12.10.1940
604	U-69	30.05.1938	11.11.1939	19.09.1940	02.11.1940
606	U-70	30.05.1938	19.12.1939	12.10.1940	23.11.1940

These orders were placed in the Germaniawerft AG in Kiel.

It looks like the first five type VIIC boats (U-93, U-94, U-95, U-96, U-97) where equipped with two electrically driven compressor, while all later with one electric and one diesel compressor. And that's why, on the plans from the U-570 there were drawn both versions of the equipment.
U-570 were ordered on 16.10.1939 in Blohm & Voss in Hamburg and laid down, launched and commissioned on 21.05.1940, 20.03.1941 and 15.05.1941 respectively. She was for sure equipped with the Junkers compressor (according to photos and reports).

Quote from: tore on 07 May , 2012, 10:59

Anyhow the Junker compressor was a wonderful machine, totally balanced, it was however susceptible to carbon deposits on the dieselside which was upsetting the delicate balance and thus required a fairly frequent maintenace.

I have got interesting quote from the book "Diesels for the First Stealth Weapon":

Quote

The author remembers his experience on a similar Junkers unit when a graduate student in 1954. One from a submarine and brought to America after 1945 was set up in Stanford University laboratory for experimental purposes. Not in the best of condition, it usually failed to start which meant cranking the pistons together again - and again. It was also extremaly noisy, and one can only imagine how it sounded inside a U-boat; the silence was deafening when it stopped. However, it was so finely balanced that a coin remained standing on edge while the engine was running. Thus fifty years later in Kiel it was a pleasure to hear one again albeit still as loud as remembered.

One of these compressors is shown in the Maschinenmuseum in Kiel-Wik, where it provides compressed air for starting the MWM RS 34 S engine (another submarine diesel).
http://www.youtube.com/watch?v=aH688UAAfUw&NR=1
http://www.youtube.com/watch?v=5eCq33orEaA&feature=related
http://www.youtube.com/watch?v=jg3iMp-7RcE&feature=related
http://www.youtube.com/watch?v=VhNbfunBLSs&feature=related

--
Regards
Maciek

tore · « **Reply #82 on:** 07 May , 2012, 23:09 »

Junker compressor again.
In the navy workshop they actually once startet the compressor hanging in a wire and it was running withouth bouncing around. As you qoute Maciek it was very noisy, but so were the main diesels as well in the confined space. Ear protectors were unknowm in those days, no wonder my hearing is gone, but the Junker design was wonderful.
Tore

Marko · « **Reply #83 on:** 08 May , 2012, 00:39 »

Erm, so if i am modeling the U-96, i should make 2 electrical compressors instead?

SnakeDoc · « **Reply #84 on:** 08 May , 2012, 03:06 »

Quote from: Marko on 08 May , 2012, 00:39

Erm, so if i am modeling the U-96, i should make 2 electrical compressors instead?

Well, I would do so.

--
Regards
Maciek

tore · « **Reply #85 on:** 08 May , 2012, 09:57 »

Poor you Marko, but this is the result of good resarch as so many others have been doing before you and that is why this kind of work is interesting, no ready made desciption to follow and each work becomes different and unique. Look at the enormous research and work of Simon during many years and Christophers challenging task! I`m very impressed by these guys and the tireless labours with foreverlasting alterations. Keep going you have an interesting project ahead of you.
Tore

Marko · « **Reply #86 on:** 08 May , 2012, 11:13 »

He he, well im doing my best. We had another brief conversation today regarding printing, and at the moment machine needs few components replaced in order to gain accuracy, this will be done by summer, and then we will need test subjects anyways, so we decided that this could be ideal project.

back to the drawings, i've added a torpedo pulley, few smaller generators, or electric motors?, boxes, few locating pins for larger valve wheels, this compartment is detailed actually 70% with wiring and plumbing, so i wont be able to do much this ways, that will be added after print outs will be made, with copper, aluminum and lead wires, different diameters.

have i missed anything crucial perhaps? Did have this compartment any guiding rail for torpedo loading or was it handled pretty much by pulley? I have also made the torpedo loading hatch, but the actual hatch with its closing system will be taken from CMK's set, since i am unable to recreate it with this technology (would need photoetching)

tore · « **Reply #87 on:** 08 May , 2012, 12:27 »

I`m not sure if you got the e-motor for the steeringgear in. It is a fairly large motor fitted atwarthship and connected to the geardrive where the rod from the emergency steering is entering. May be you recognize it on the posted picture.
Tore

SnakeDoc · « **Reply #88 on:** 08 May , 2012, 13:24 »

Hi

I would also add the electric motor and steering gear for the aft diving planes and air fans for the main electric motors.

--
Regards
Maciek

Marko · « **Reply #89 on:** 08 May , 2012, 14:16 »

well, i added the steering gear motor, at least i think i did, (cylinder 90

tore · « **Reply #90 on:** 08 May , 2012, 23:34 »

Have you decided to keep the Junker? In that case the aft part of it, containing stage 3 & 4, is tapering towards a smaller diameter at the end. This migth give you a bit more space.
Tore

SnakeDoc · « **Reply #91 on:** 09 May , 2012, 03:50 »

Hi Marko

Quote from: Marko on 08 May , 2012, 14:16

but im not sure how should i make the cooling fans for E-motors, i have no photos, and im not sure how large they were (maybe again possible only with photo etching to create fan blades? - if those were small then its virtually impossible, unless if id made fan blades from thin metal myself, and only fan housings, but then again i would need photos of those.

I mean this part:

See also Simon's drawing:
http://models.rokket.biz/index.php?topic=106.msg10552#msg10552

--
Regards
Maciek

Marko · « **Reply #92 on:** 09 May , 2012, 04:03 »

Oh those are cooling fans, then it should not pose much of problem, will get right on them. Is dive plane mechanism more or less OK? I will have to seriously modify the compressor, since i noticed as Tore said, that i forgot tapering it..

SnakeDoc · « **Reply #93 on:** 09 May , 2012, 04:05 »

Quote from: Marko on 09 May , 2012, 04:03

Is dive plane mechanism more or less OK?

Seems to be ok. Could you provide another view (toward aft, a little closer to center line)?

--
Regards
Maciek

Marko · « **Reply #94 on:** 09 May , 2012, 09:03 »

Sure Maciek, here it is, along with tapered compressor aft section:
(few layers disabled in order not to obscure view)

tore · « **Reply #95 on:** 09 May , 2012, 11:02 »

Well you have got a lot of stuff in. One interesting item is not in though, it`s what the Germans called Pillewerfer. It was mostly the torpedopeople operating this device so I don`t know too much about it. The device was used for ejecting various canisters while submerged. One of the canisters contained magnesium (I believe) pellets which in contact with seawater created a big "bouble" making an object for false Asdic contact, another type made an oilslick. The idea was to fool the enemy surfacechaser. We used it quite frequently during excersises shooting ligth rockets indicating torpedofiring. The size of the canisters were approximately 10-12 cm diameter and the placing of the ejector was stb. side in the area next to the Junkercompressor as far as I remember. I have tried to localize it on the pictures I have but are unable to trace it. The device is often descibed in the uboatnovels and I believe its an interesting device to put in. I have seen only very few models incoporating this device. May be somebody can furnish further details. I`m posting a few pictures showing the ejectorslot in the external casing so you are able to localise the where it`s fitted.
Tore

SnakeDoc · « **Reply #96 on:** 09 May , 2012, 11:22 »

Tore

Here it is:

See also:
http://u-historia.com/uhistoria/tecnico/visitaguiada/lanzasenyuelos/lanzasenyuelos.htm

--
Regards
Maciek

tore · « **Reply #97 on:** 09 May , 2012, 12:23 »

Rigth Maciek that`s how I remember it. Thank you.
Tore

Marko · « **Reply #98 on:** 09 May , 2012, 12:34 »

Hmm it would be a great addition, however the starboard side is exactly the one where the hull will be opened, and the very same position of the pillenwerfer is approximately 1,5 cm away from the rear end, which brings it to spot where the cut out will be, and i have no idea how could i add it, obviously it cant float in mid-air, unless if i could make some kind support for it., maybe if i would add thick piping on top of the torpedo compensating tanks, but that would not look esthetic in my opinion. Transparent holder is also not really appropriate, since it would be visible, should i leave it out?

I'll get to the E-motor cooling fans for now, and will wait for your opinion regarding the pillenwerfer.

TopherVIIC · « **Reply #99 on:** 09 May , 2012, 12:53 »

Marko,
On my 1:35 cut-away I actually have some "floating" items supported by electrical cables and airlines, but I am also doing the T-bulb D.Spt frames as visible. I am only removing the skin, so it works for me. I agree with you in your case - floating the pillenwerfer would not work so well.

Marko · « **Reply #100 on:** 09 May , 2012, 13:06 »

Hm, electrical cable sounds like a good idea, but unfortunately around pillenwerfer there is nothing such thing to see

There are some thin pipings, but i am afraid that such thin wire would not properly support the solid part such as pillenwerfer mechanism

tore · « **Reply #101 on:** 09 May , 2012, 13:28 »

I think I localized the device on the picture below, and it seems to be fitted to the pressurehull right above the last aft flange of the Junker housing. I`m not at all an expert on this kind of drawings, but could you extend the hullskin just a bit to provide the fitting. To my opinion it would be a great asset to drawing if you could manage.
Tore

Marko · « **Reply #102 on:** 09 May , 2012, 14:02 »

hmm, currently is in scale 1/72 compartment approximately 105 mm long without the extension. I'd rather not try to shorten it, but i got an idea while you said "right above the last flange of Junkers" well, i could fit it to the bulkhead that limits the compartment (see the attachment) I also made the cooling fans and its electronics, and i totally forgot about the side motor mounts, so those are in place now, i think those are really nice detail, and add to overall depth of the E-propulsion. check out my propositon for the Pillewerfer location.

TopherVIIC · « **Reply #103 on:** 09 May , 2012, 14:05 »

The thing to remember also is that this is a base casting. Each modeler can add wiring, plumbing and details as desired. Your final build will not be limited to just what you build and print here!

tore · « **Reply #104 on:** 09 May , 2012, 14:29 »

Christopher has a wise remark and following that I would advise to put it a bit further forward as I try tro indicate on your drawing.
Tore

Marko · « **Reply #105 on:** 09 May , 2012, 14:43 »

Erm, Tore that on the drawing is the stern hydroplane mechanism (you marked it as pillewerfer), however i think best possible location for Pillewerfer would be on that spot, unless if i make some extension, or i could make it separately, and then decide where to put it, and how to attach it. Or, in theory i could lean it to the last flange of the Junkers compressor, which would not be entirely accurate, but would follow the flow of the parts..

here is approximate position of the pillwerfer, im not exactly sure how would this fall out, basically its a tube rotated 90

tore · « **Reply #106 on:** 09 May , 2012, 23:20 »

Yes Marko, this seems to be rigth seeing it from this angle. As to the fixing how about a plexiglass frame (skin)? I have not the faintest idea about this technique.
Tore

Marko · « **Reply #107 on:** 10 May , 2012, 00:05 »

I have thought of it too, but then i would have to close up all of the compartments this way and that would not be easy due to hull curvature.i thought as second option a small spacer between Junkers compressor and the pillewerfer, in dimension 1x1, or maybe even 0.5x0.5, and appropriate length. Well, i will complete it, still have to move it for about 2 mm towards front end, and then will try the pillar support method how it will show out, later i could dress up the pillar with some wiring and plumbing...

here it is, pillewerfer along with its pillar, i hope that it will be enough to support it, pillar is around 1,5 mm long with cross section of 0.5x0.5, so it will be barely visible. With some shading i can almost render it invisible, and some additional wiring could also help.

Marko · « **Reply #108 on:** 10 May , 2012, 10:36 »

i decided to zoom it in, now the length of the pillewerfer is as long that it reaches the outside of the hull, somehow seems too long, and does nto fall into the context of the part stream. should i shorten it for one quarter? I also added some of the walve and control wheels, note, these are just most visible, i will try to make theese in large number and place them accordingly wherever needed, if the prints of the wheels would prove not to be OK, i hope that i could find these control wheels Photoetched somewhere, maybe HO scale from the train modelers...

i got ahead of myself and pre-made the shorter variant and will take votes which is better

tore · « **Reply #109 on:** 10 May , 2012, 10:52 »

As it looks now it`s a cut off which migth be OK. In reality the outer end is within the slot in the casing and has a pressuretight cap beeing able to open and shut by a small wheel inside next to the Pillenwerfer.
Tore

Marko · « **Reply #110 on:** 10 May , 2012, 11:05 »

hm, makes sense, since somehow the pill (oil canister, sonar decoy, trash?

) had to be loaded. Should i make vertical cut to the tube, or should i leave it angled as the hull falls around it?

tore · « **Reply #111 on:** 10 May , 2012, 11:33 »

Marko
Ejecting 46 mens trash trough a 10 cm tube would keep a man busy for hours and leave a nice track behind you. If you make a cut I think you should leave it angled just to indicate it is a cut.
Tore

Marko · « **Reply #112 on:** 11 May , 2012, 05:42 »

Okay, shorter angled it is. I am out of ideas what else could i done on it. Any suggestions or should i start exporting and creating suitable files and then start on the conning tower interior?

TopherVIIC · « **Reply #113 on:** 11 May , 2012, 06:07 »

Marko-
Sometimes it is useful to change tracks. As you work on the conning tower you may subconsciously come up with solutions to other areas. That happens to me all the time. :-)

Marko · « **Reply #114 on:** 11 May , 2012, 06:24 »

True indeed,

i just edited few items in the forward crew compartment

uhm, CMK did in the fwd torpedo compartment a guiding rail (I beam) for loading torpedo into torpedo tube. Did the rear compartment had same rail with a wheel to force the torpedo to the tube, or did they use only that pulley located in the "middle" of the compartment along with chains? Im asking, since i cant find any guiding rail from the photos from Laboe, neither from panoramas.

SnakeDoc · « **Reply #115 on:** 11 May , 2012, 08:21 »

Hi
Coming back to the Diesel compressor:

Quote from: SnakeDoc on 07 May , 2012, 16:19

It looks like the first five type VIIC boats (U-93, U-94, U-95, U-96, U-97) where equipped with two electrically driven compressor, while all later with one electric and one diesel compressor. And that's why, on the plans from the U-570 there were drawn both versions of the equipment.

Now it is clear for me, why among the installations drawings from the U-570 (http://uboatarchive.net/U-570DesignBook.htm), there are three plates for the cooling system - 13, 13A and 13B. There are for the type VIIC boats with GW Krupp Diesel engines with Diesel air compressor, with MAN Diesel engines with Diesel air compressor and with the GW Krupp Diesel engines with two electrically driven compressors respectively.

If you compare these drawings, you will see the additional cooling installation for the Diesel air compressor exhaust line.

--
Regards
Maciek

tore · « **Reply #116 on:** 11 May , 2012, 10:30 »

Which fits in with your statement Maciek, that U-93 up to U-97 would have two E-compressors as these boats were built at Krupp Germaniawerft and would the have the GW mainengines.
Tore

Marko · « **Reply #117 on:** 11 May , 2012, 11:12 »

hmm, is it possible that pillewerfer was only on the later built submarines?

tore · « **Reply #118 on:** 11 May , 2012, 12:40 »

Quote from: Marko on 11 May , 2012, 11:12

hmm, is it possible that pillewerfer was only on the later built submarines?

I guess it depends what you mean by later. As far as I know it was introduced in the U-boats latter part of 1942. But you know it was relatively easy to fit the Pillenwerfer on all the Uboats.
Tore

SnakeDoc · « **Reply #119 on:** 11 May , 2012, 14:02 »

Marko,

Quote from: Marko on 11 May , 2012, 11:12

hmm, is it possible that pillewerfer was only on the later built submarines?

According to R

Marko · « **Reply #120 on:** 11 May , 2012, 16:29 »

okay, pillenwerfer stays in place then

Uhm, could anyone help me with drawings from conning tower interior? I have only few, and very few photos aswell, so any drawings and photos are welcome

tore · « **Reply #121 on:** 11 May , 2012, 23:14 »

Well, I start with the dominant part of it, the attackperiscope. For that time it was a very advanced piece of equipment, see drawing below. The CO sat on the seat which could be turned around by telemotor controlled by the feet on the pedals below.
Tore

SnakeDoc · « **Reply #122 on:** 13 May , 2012, 01:26 »

Marko,

Quote from: Marko on 11 May , 2012, 16:29

Uhm, could anyone help me with drawings from conning tower interior? I have only few, and very few photos aswell, so any drawings and photos are welcome

Create the hull of the conning tower, then make the fixed-eye periscope as Tore suggested, and then will see.

--
Regards
Maciek

tore · « **Reply #123 on:** 13 May , 2012, 04:26 »

When Maciek adviced to create the hull of the conningtower I all of a sudden seems to remember the steel thickness was considerably thicker than the average pressuserehull. Somehow I seems to remember 40 mm, anyhow on a 41. May be somebody can confirm this.

Tore

SnakeDoc · « **Reply #124 on:** 13 May , 2012, 04:42 »

Quote from: tore on 13 May , 2012, 04:26

When Maciek adviced to create the hull of the conningtower I all of a sudden seems to remember the steel thickness was considerably thicker than the average pressuserehull. Somehow I seems to remember 40 mm, anyhow on a 41. May be somebody can confirm this.

According to U Bootskunde f

tore · « **Reply #125 on:** 13 May , 2012, 05:15 »

Nice to have it confirmed that I`m still not in the alzheimer stage.`
Tore

Marko · « **Reply #126 on:** 13 May , 2012, 09:07 »

hrm, according to my lectures at university if i remember them right (quite some while ago) here is the theory why the conning tower walls had to be thicker:
1) optimal shape of the pressure vessel is round due to tangential pressure, and due to the impact angle of the pressure force the components of the force get significantly lower value - especially the active component which has lower impact to the affected surface (similar as sloped armor on armored vehicles), with the pressure hull that is achieved as a cylinder, which has rounded ends, which assist at the structure integrity, where welds are critical points - that is why hull is not riveted together, since rivets could get sheared off, compromising the interior. Ideal shape of the submarine would be in this case - round shape, but that would obviously increase drag, not to mention how would be submarine large in diameter...

2) since the conning tower cannot have rounded top, and the joint between pressure hull and the conning tower is basically perpendicular, the welds have to be particularly strong, so have to be walls of the compartment to cancel the pressure effects out. For instance, pressure hull is rounded, and can have for this reason walls thick lets say 20 mm, where the conning tower has to have to get same results that at least doubled, could be thinner, but therefore different type of alloy should be used.

So if i remember my theory right, these are the main reasons why the aft and bow are substantially thinner than the rest (full round shape), main hull sides thinner since they have rounded tips, and the thickest conning tower components, due to flat cap. Okay, no on to the new topic for the conning tower

p.s.: feel free to correct my theory, or add new reasons

tore · « **Reply #127 on:** 13 May , 2012, 10:02 »

Basicly you remember the theory correctly, I believe. The practical result of same is, as the conningtower has a considerable oval structure, the steel having the same tensile strength is thicker to compensate for the increased stresses. I believe the steel plates of the pressurehull in the joint area of the conning tower has an icreased thickness as well allthough not to the same extent as the conningtower. (I don`t know this for sure). As an oval opening in the pressurehull, cause a considerable weakness in the pressurehull in addition to cutting of the frames, the two torpedoloading openings (fore and aft) have loose beams which are fitted in craddles as a continuation and completion of the framecircles.
Tore

NZSnowman · « **Reply #128 on:** 13 May , 2012, 19:46 »

Quote from: SnakeDoc on 13 May , 2012, 04:42

Quote from: tore on 13 May , 2012, 04:26
When Maciek adviced to create the hull of the conningtower I all of a sudden seems to remember the steel thickness was considerably thicker than the average pressuserehull. Somehow I seems to remember 40 mm, anyhow on a 41. May be somebody can confirm this.

According to U Bootskunde f

NZSnowman · « **Reply #129 on:** 13 May , 2012, 19:56 »