Virtual Biber Build

[lucky13dave]

Hello everybody,

I've been following Russ' 2 autocad builds for some time and am quite impressed with his work. As I've posted in his thread on the Batfish build, he's inspired me to start a virtual build of my own.

Unlike Russ, I don't specifically plan to have it 3D printed; it's an option I'll keep open, but I plan on using the computer model to test the feasability of some other options.

I will be building this model in SolidWorks, as I've recently gained access to the software through my work. I've been playing around with it for a few months now. I've built a few versions of the bow already. None of them seem quite right, some of them have bugs that prevent them from building into a solid properly. It has been fun, frusterating, and rewarding. I've Learned a lot along the way.

I hope you enjoy the build! Thanks,

David

[lucky13dave]

Earlier Attmepts

Here are a few images of a recent attempt. I've got some questions I want to settle before I proceed too far, But I'm getting a handle on building the model. I started with the bow because it seems to be rather detailed, and the hardest part to get right. A lot of the variations from build to build concern details that aren't defined in the drawings I have, So I've been downloading & referencing as many photos as I can.

[lucky13dave]

A Big Dilema...

I have some plans that I downloaded, as well as a set in a book I purchased from a memeber here, Ubootwaffe. (those plans kinda got me obsessed with this boat.)

There are variations from plan to plan, as well as discrepencies b/w the plans and the photos I've found. My Brother in Law is in London, and said he'd be willing to go to the Imperial War Museum and get additional photos, and maybe measurements if possible. In the meantime, here are 2 drawings made off different plans that illustrate an example of the discrepencies.



In this sketch, made off an image form Ubootwaffe, I drew a circle with a 533 mm diameter. I resized the image to tha tthe torpedo was sized to match this circle. I drew a vertical line and rotated the image so it was oriented with this line and the torpedo was concentric with the circle. I matched the verticle line top and bottem to the image, then drew arcs to match the image. I did redimension the features to give me these nice round numbers, but they match up pretty well. This gives a hull 1000 mm tall, with the upper half an arc of 480 mm ( matches the stated hull dia. of 960 mm) but the lower arc is 575 mm, with its center above that of the upper arc. the torpedo center is 520 mm from the centerline, and 275 mm below the center of the upper arc, 255 mm below the hulls center.




This sketch is based off an image from the interwebs (I don't recall exactly where at this point.) This and others show the hull being circular, with cutouts for the torpedos. again drawing a 533 mm circle, scaling the picture up to size the image. Here a 960 mm circle matches the hull very well. I didn't straighten the image, but matched one torpedo and the hull. I added another 533 mm circle, matched it to the other torpedo, and added a centerline. I drew a centerline through the 960 mm circle, and made it perpendicular to the torpedo CL. I measured the distance from the left torpedo to the hull CL, and made the second circle the same distance The 510 mm dimension is the same as the first sketch I posted, but the CL distances vary, as well as the overall hight.

I am wondering if anybody knows much about this boat, which profile is closer to the actual one. Any advice or opinions would be welcomed.


Thnaks, Dave

[JWLaRue]

Re: Virtual Biber Build

Dave,

The book you are referring to, Ubootwaffe...is that the large hardcover titled Ubootwaffe, Marine - Kleinkampfverbande 1939-1945 by Waldemar Trojca?

What happens if you use a torpedo diameter of 534.6mm? Does it make thing work out better? A diameter of 534.6mm would be the correct diameter for the German G7e torpedo and its various different variants.

-Jeff

[subicman]

Re: Virtual Biber Build

Dave,

I am currently researching this boat as I have a model hull for one that I got for cheap a while ago. I have been doing the same thing as you have in the 3d drawing world except I have been using Autodesk Inventor. The bow is tricky as hell and I still do not have it right. I recently was able to take a load of meaurements from one of the surviving boats. Unfortunately, I was not allowed to take pictures as the boat sits outside of the Norwegian Navy's Dive locker on their base in Bergen, Norway.

The boat is on display and has been heavily modified as it was used by the Norwegian Navy after the war for several years. The hull is circular in construction and the torpedo stows hung off the sides with the sides cut in to make room for the torpedoes girth. The boat was assembled in 3 sections, the Bow, Mid and Stern. The boat in Norway had the vents for the original ballast tanks welded shut and ballast tanks welded onto the boat covering the torpedo cutouts, but I got dimensions and distances of all the original equipment and mounts based on the set of plans I have and the obvious weld lines over the equipment locations.

I spent a good deal of time talking to the sailors their and was invited over to what they call the Periscope hut. Basically it is a log cabin on an island in the Fjord that houses their Submariners club. In addition to being offer a lot of free booze, I also got to see a good deal of history and talk with some of the old timers per say. The Norwegian Navy operated captured Type VII submarines for several years after the war. There were pictures on the wall showing several boats operating out of Bergen and some pictures from inside Bunker 'Bruno" The bunker is still used to overhaul their current submarine fleet. Part of the periscope hut is the wardroom area out of one of the captured Type VII's and I was sitting on the original benches and was looking at some of the original cabinetry that was used onboard. But this is going off topic.....The real story is that they operated the Biber for about 10-15 years as part of their "coming of age" time for their divers.

I am still compiling the data i took over several pages of notes, and making it more presentable. I would be happy to answer any questions regarding the measurements I took. They are in inches tho.....and I have to convert to metric.

V/R
Tim

[lucky13dave]

Re: Virtual Biber Build

Dave,

The book you are referring to, Ubootwaffe...is that the large hardcover titled Ubootwaffe, Marine - Kleinkampfverbande 1939-1945 by Waldemar Trojca?

What happens if you use a torpedo diameter of 534.6mm? Does it make thing work out better? A diameter of 534.6mm would be the correct diameter for the German G7e torpedo and its various different variants.

-Jeff

Jeff, thanks for the reply. That is the book. And the plans in the book are great, but do leave me with plenty of questions. They seem to be more of a drawing made for or from the 3d rendering presented in the book, and do have some departures from the photos of the boat. If it is the case that is is for/ from a 3d rendering, especially one designed for grapghic use (ie a video game) that could explain such deviations.

Thanks for the 534.6mm dimension, I've noted it and will use it. It doesn't change much in my sketches though. In sketching over these drawings, the drawings are blown up to the point that they lose resolution. SW will keep the high resolution of the circle I sketch, but the drawing becomes pixelated. I Did a sketch with the overall hull hight at 960 mm][/url]

It may explain the difference; the 534.6 mm circle fits nicely into the cutout for the torpedo, and the torpedo itself is drwn smaller (I sketched a circle that looked to fit pretty well, and displayed the dimension without modifying it.) The circle from the drawing that represents the torpedo is significantly smaller than the true dimension of the actual torpedo.

[lucky13dave]

Re: Virtual Biber Build

Tim,

Good luck with your build! I reckon that I'll have a TON of questions for you. And I am very interested in your measurements. If you want any help with Inch Metric conversions, let me know, I do that constantly at work, (print comes in in metric , machines and inspection equiptment are in inch, yada yada,) and am more than willing to do that sort of grunt work. And I reckon I can help get it into presentable form

You sat in a the ward room from a VIIc? Yowza!!! That sounds like a great experience, I'm a little green eyed!

If you're interested in collaborating, lemme know. Even though we're using different software, I think we could help eachother.

I think that whats made the bow so tricky for me is partially my approach; I'm trying to consider how the boats were manufactured to model it, and I presume, but haven't done the historical research,that they were built at many shipyards, and construction wil show variations from yard to yard. I can picture workers with sledge hammers nudging the steel in the bow to a better fit Add post war modifications, and I've got more question marks.

Dave

[JWLaRue]

Re: Virtual Biber Build

Dave,

The drawings/plans for the more 'common' U-boat variants are easy to come by and tend to be quite accurate. For a number of reasons documentation for the late(r) war boats like the Biber is hard to come by. Even when examples, again like the Biber, still exist in museums. You may be able to get some accurate measurements if you contact one of the museums. I suspect that it may take only a few critical measurements to satisfy.

-Jeff