Model Boat Mayhem

Dry Dock / Shipyard: Builds & Questions => Submarines => Topic started by: JosephHuntley on October 28, 2016, 07:05:56 PM

Title: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 28, 2016, 07:05:56 PM
Hi guys new to boats and subs but I been designing and building r/c aircraft for 40+ yrs.
 
 I am wanting to get into subs and have always been one for stuff with a lot of fidgety external stuff so I could have fun making all those scale details. I also like to use solidworks to cad up my designs so I get to see it in 3D before I build thne I can export off for CNC work etc.
 
 I am wanting to do a type VIIB or VIIc german U boat. my problem is
 
 1) I dont do kits to me most are a waste of money as I usually have to replace tons of contents because they are inferior quality
 
 2) I am a designer and scratch builder I only like to build from  a set of plans or of my own design (it is just the satisfaction I get plus the best way to learn stuff via trial and error)
 
 3) I am new to boats and subs as being an plane guy for so long. so I have tooked around for drawings and most are really low quality  or small and very hard to read. this makes it hard for me to start any cad work if I cannot see the proper shapes or the location of the bulkead they are showing.
 
 so does anyone have or have a link to a good clean set of drawings for  a type VII?
 
 I did look in the reference section last night but didnt seem to find a good clean image unless since im old and vision going (turned 55 yest )) i just happened to miss one
 
 thanks Joe
 
 ps when i find the info i will prob post my design as i progress so it easier to ask for help or so ppl can correct me if I dont take something into consideration for running gear etc.
 
 my plan is for possibly 1/32 scale or if i can find a way to break it in the middle go 1/16th scale
Title: Re: German type VIIC or VIIB Uboat
Post by: JimG on October 28, 2016, 10:12:02 PM
Look for the book "The Type VII U-Boat" by David Westwood, one of the Anatomy of the ship by Conway Maritime press ISBN 0 85117 3141. This has some very good drawings of both external and internal details.
Quite likely to be expensive from a specialist bookseller unless you a re lucky to find it on  eBay.

Jim
Title: Re: German type VIIC or VIIB Uboat
Post by: TomP on October 28, 2016, 10:22:51 PM
Hi Joesph, have a look on the German EBay for planmappe uboottyp VIIC will find a very detailed set of drawings. OTW do a very accurate type VII c rivet counters might find errors but it is a fantastic model and Bob is great to deal with. A1:32 type IX C would be nice not many of those about!
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 29, 2016, 06:14:53 AM
thanks guys I do have that anatomy of the ship book but that is a type II though im not that familiar with subs but think its a bit different from the type VII

on another note I do have decent dxf file of bulkheads and outlines for a japanese I-400 but it doesn't have all the cool scale fidgety parts of the type VII. I don't care what sub I do but want to do one with a lot of fidgety parts so it looks like something other than a tube with blunt nose. plus all the gas/air escape holes (cant remember proper term) on the type VII give it some character
Title: Re: German type VIIC or VIIB Uboat
Post by: Davy1 on October 29, 2016, 10:58:29 AM
Welcome to the wonderful world of subs! It is also very nice that you are looking at scratch building, which is a little rare.

You also have a different approach in that you have not mentioned the "innards" (the inner working bits) which I suppose is the fascination (maybe over fascination!) of most model submariners.

Do have a look at a new website (Thanks to Tim G) it has a lot for the scratch builder and it also goes through the main dive systems:

http://associationofmodelsubmariners.com/ (http://associationofmodelsubmariners.com/)

I would also  suggest getting hold of a copy (sadly now out of print) of:

"Model Submarine Technology" by Norbert Bruggen.

Welcome again and good luck with the build.

David
Title: Re: German type VIIC or VIIB Uboat
Post by: JimG on October 29, 2016, 12:19:53 PM
thanks guys I do have that anatomy of the ship book but that is a type II though im not that familiar with subs but think its a bit different from the type VII


The book I mentioned is definately the type VII, I have a copy sitting on a shelf about 3 feet from me. O0
The only other book in the series about u boats was the type XXI.
You could try the Haynes manual
https://www.amazon.co.uk/U-Boat-Manual-Owners-Workshop/dp/0857334042/ref=pd_sim_14_2?_encoding=UTF8&psc=1&refRID=HJ5ASWH9DWT4BHSNCBC0
 :D

Jim
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 29, 2016, 05:44:51 PM
thanks guys i have the haynes book but dont care for the 21 too bland outside plis i always hate when drawings are cut up and you have to piece together. i will look for the other book though.

I think I found some good drawings. i posted on r/c groups and a guy gave me a link to what you guys would consider excellent drawings i just consider them adequate enough i can try to be dangerous. so I think I will go with the D and then I can use some corks add spikes and lay mines at the pond ))  so maybe today I can start layint it out. I will lay it out at 1/16th scale and set everything up wood dimensional wise so i can reduce to 50% easily but still have the larger version in case I can figure out how to cut it in half and still be able to assemble it water tight at the pond

http://www.24flotilla.com/ODSH/tecnica/t2/TipoVIID-Big.png (http://www.24flotilla.com/ODSH/tecnica/t2/TipoVIID-Big.png)

http://shipbucket.com/Misc%20Drawings/FD%20Scale%20Vehicles/Ships%20-%20Real-life/Germany%20-%20SSK%20U-VIID%201941.png (http://shipbucket.com/Misc%20Drawings/FD%20Scale%20Vehicles/Ships%20-%20Real-life/Germany%20-%20SSK%20U-VIID%201941.png)

Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 29, 2016, 06:50:55 PM
I found these station drawing I think they are for a type C but would pretty much be the same as the main difference I could find is the type D is longer

for some reason my math isnt working out as the ship was 32 ft 10 inches and when I try to divide it by 16 i only get like 2 ft which doesnt sound right. when i do planes and divide by 24% or 33% i get proper numbers.
Title: Re: German type VIIC or VIIB Uboat
Post by: unbuiltnautilus on October 29, 2016, 06:51:57 PM
Two separate water tight compartments, one in the fore hull and one in the aft hull. Would also make it easier to work on, half a boat at a time!
Title: Re: German type VIIC or VIIB Uboat
Post by: Subculture on October 29, 2016, 06:56:11 PM
Good luck with your build. I do hope you realize the fun and games you will have getting a boat this size in and, more importantly, out of the water.
Title: Re: German type VIIC or VIIB Uboat
Post by: unbuiltnautilus on October 29, 2016, 06:57:32 PM
I found these station drawing I think they are for a type C but would pretty much be the same as the main difference I could find is the type D is longer

for some reason my math isnt working out as the ship was 32 ft 10 inches and when I try to divide it by 16 i only get like 2 ft which doesnt sound right. when i do planes and divide by 24% or 33% i get proper numbers.


That Wikipedia thing has the D as 32' 10" LONGER than a standard Type VII. Add another 220' to that gives you 252' approx.. now, divide that by 16, that's big!
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 29, 2016, 07:08:32 PM
not sure what you are meaning with the ' mark in the US here that is feet I am guessing you meant inches. im getting 32' x 12" = 384" + 10" for a total of 394" then divided by 16 comes to 24 which doesnt seem correct. of course i havent sl;ept for 38 ish hours so maybe i am tired and missing something
Title: Re: German type VIIC or VIIB Uboat
Post by: Subculture on October 29, 2016, 07:18:40 PM
15.75 feet long.

Also don't forget the displacement goes by the cube of the scale. So whilst a 1/32nd scale Type VII, will displace around 23kg, a 1/16th scale boat will displace about 188kg!!

Even if it's in two parts, that will still be a substantial weight to lug about.
Title: Re: German type VIIC or VIIB Uboat
Post by: unbuiltnautilus on October 29, 2016, 07:21:29 PM
I knew I should have gone metric all those years ago!
We may be at cross purposes, but I assumed the aim was to establish the models length at a scale of 1/16.
Yes those little (') in my world are feet or ft, while their cousins (") are inches or in. I never realised this was not a universal method of indicating feet and inches. As you are still championing the imperial system, you may continue however you see fit  :} .
Using pen and paper, and having been dealing with customers all day, I have roughly calculated a 252 ft sub, scaled down to 1/16, at roughly 16 ft long.. big.


Took me so long I got beaten to the punch :-))
Title: Re: German type VIIC or VIIB Uboat
Post by: microgyros on October 29, 2016, 07:27:42 PM
... I will lay it out at 1/16th scale and set everything up wood dimensional wise so i can reduce to 50% easily but still have the larger version in case I can figure out how to cut it in half and still be able to assemble it water tight at the pond
I suggest a fifteen foot sub would be better in three unequal sections with a 120mm diameter water tight area in the middle portion. Fore and aft would be entirely free flooding.
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 29, 2016, 07:42:26 PM
thanks guys I still don't know what I will actually build scale wise but if I draw it at the larger scale of 1/16th then if I decide to just go 1/32 it will be easier than going from smaller 1/32 then decide to upgrade it to 1/16th.

so soon I will prob start my design/build thread so that way when i do something stupid or without thinking (which will happen a lot since this isn't a plane and i'm totally lost) then someone can chime in
Title: Re: German type VIIC or VIIB Uboat
Post by: microgyros on October 29, 2016, 08:18:32 PM
That was crystal clear but it isn't so clear if you understood there is no need to divide up a wtc compartment and assemble it at the pond.
How big did you think a wtc for a 15 foot version would be?
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 29, 2016, 08:23:39 PM
dunno yet it depends on how much working goodies I add I assume like the hatches for the torps then torp launch mechs then hatches  for the mines then theres the periscope lol lot of working stuff so lot of servoes etc need for yada yada


some super factory drawings for us sub in case ya didnt see my post
https://www.maritime.org/tech/drawings/index.htm#super (https://www.maritime.org/tech/drawings/index.htm#super)
Title: Re: German type VIIC or VIIB Uboat
Post by: microgyros on October 29, 2016, 08:43:47 PM
You want to construct the clever stuff in the free flood area of a model with servos in the wtc. The wtc would just protrude from centre section bulkhead joints. There is probably something like that shown in the Nautilus Drydocks.
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 29, 2016, 08:47:36 PM
ok thanks the first thing i need to think about is just getting the base forms designed then work out the other stuff
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 29, 2016, 11:48:39 PM
well having trouble reading lot of the info so I am thinking of looking into the Uss Pompanito which was a Balo class since I found that site with tons of factory drawings if I find enough good ones i can cad from it would be great since its first sub. would rather do the type 7d but i dont know enough abt subs to get the outlines correct. i tried every trick in the book but the drawings were just too low quality and degraded when trying to enlarge to read
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 30, 2016, 06:26:54 AM
well got everything downloaded now laying out the stations the first 35 are 24" apart then some at 30" then back to 24"

(http://www.proflooney.net/Subs/Balao-01.png)
Title: Re: German type VIIC or VIIB Uboat
Post by: nemesis on October 30, 2016, 05:25:53 PM
Get in touch with the German Naval Museum at Laboe, they may be some help. I got my TypeVIIc 41-43 plans from Germany some years ago and when I went to hunt them out they had been printed on thermal imaging paper and all I had were blank sheets of paper. Keep digging and delving, you never know what turns up. Nemesis
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 30, 2016, 05:50:22 PM
thanks but for now I got shipyard drawings for the USS Pompanito Balao class sub and it has lot of fidgety on the decks as well so I am going to do that one. it will take a couple days for me to set everything up in cad due to a lot of dimensions and planes needing created
Title: Re: German type VIIC or VIIB Uboat
Post by: RAAArtyGunner on October 30, 2016, 10:21:48 PM

So it won't be German but American???????
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 31, 2016, 05:01:47 AM
correct my first one will be american since my german stuff was so low quality and I got over 1000 factory drawings of the balao. most ppl do the gato but the balao was the next generation after the gato and at the time the largest class
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on October 31, 2016, 08:31:39 AM
Ok so tonight was able to get all the planes located for all the bulkheads. tomorrow night after work I will work on drawing out the bulkheads and getting them onto the planes ready for surface lofting my hull shape
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 01, 2016, 01:04:36 PM
well I started tracing lines and was going to try and trace them and just go for it but my problem is lines run together and some hard to discern so i think I will try to find a good top view and profile view and loft it with minimal lines then use the loft for my intermediates. dont know how it will work but will try as this is getting frustrating as i am used to cleaner top and profile outlines and not compound shapes on the hulls because of a second part of the hull like subs have
Title: Re: German type VIIC or VIIB Uboat
Post by: RAAArtyGunner on November 01, 2016, 08:36:53 PM
Joe,

Just an idea get the moderators to rename your build as American type...............?

Leaving it as German stops people finding your build
Title: Re: German type VIIC or VIIB Uboat
Post by: johnredearth on November 01, 2016, 08:56:26 PM
HI


I have got some nice plans but in your scale they would not be adequate I think.  Have you given thought as to how it will work?  The thing about scratchbuilding subs is that the end product is equally informed by the technical and the modelling.  I have scratchbuilt a V11C 1:50 and it was much harder than I thought it could be, but the work was satisfying. 


Cheers  John
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 01, 2016, 10:20:44 PM
well once i get things figured out will make new thread and delete this one

if you have them digital john and could share would appreciate as it would be a start I can always enlarge them i just need something I can loft the hull from then i can use that to get any extra formers etc i need
Title: USS Pompantio Submarine
Post by: derekwarner on November 02, 2016, 02:04:24 AM
Joseph

Renaming your thread was simple.......it now has the name of USS Pompantino, but is still linked to your original postings


When you say....'good top view and profile view and loft it with minimal lines then use the loft for my intermediates'......you mean Plan view and Elevation view, however to loft lines, you still need End Elevation views looking from on the bow and also looking on the propeller

The latest end elevation view you show looking on the bow as you say is complicated with so many closely spaced frame profiles, however there is no reason why you cannot reduce these in number and hence improve the visual clarity. Trial and error here will assist...you could consider the inclusion of every 4th frame as a starting point

Naturally there will be areas of the hull where dramatic profile or changes in section occur and in these areas referencing back to a more detailed frame spacing will be required

Derek
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 02, 2016, 02:12:26 AM
i dunno if saying it correct yes i need a top view and a side view dont need a front view.

the drawins show 3 basic parts the sub hull core (ie the main tube), the flat deck area on top of the core. and the side bulges of the outter hull.

what I need is just the center core i need the top deck and side bulges gone in order to do a proper loft as that gives me 3 things. the outlines for the top and bottom of the hull core so I can use them as guides, plus the bulkhead height in that location, and the bulkhead width in that location. I will see if I can find a screen shot of one of my aircraft lofts to explain what I mean
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 02, 2016, 02:27:01 AM
as you can see here in the blue its just the basic shape then I loft the cowl turtledeck fins etc seperate later then I will cut out any shapes that need cut out in the body. you can see the red top and bottom guides that i used for the fuse former heights and widths
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 02, 2016, 02:28:22 AM
by lofting in this way i get a clean smooth body shape and if there are more shapes like in this case the turtledeck I do them seperate. this makes the lofting of complicated things easier
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 02, 2016, 04:35:44 PM
well right now i jumped back to my 1/6th scale higgins landing craft while i try to figure out how to get the dimensions and outlines i need for lofting the hull for the sub. like I said the bulges on the side and the flat deck on top the sub hides the true outlines of the main sub body which is making it impossible to get the info I need to loft the hull
Title: Re: German type VIIC or VIIB Uboat
Post by: unbuiltnautilus on November 02, 2016, 06:11:15 PM
Maybe if you seek out some photos of these boats 'in build', when viewed without their final structures fitted, it may become clearer as to which way to proceed.
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 02, 2016, 06:35:55 PM
well the problem is i need the top and bottom of center section and the sides to use as a guide for the proper dimensions for the bulkheads to size them for the loft. I will try to find a screen shot to explain as several ppl have messaged me kinda lost what I am trying to do
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 02, 2016, 07:01:38 PM
ok in the first picture you can see top profile guide, lower profile guide, and the red line is the side or the guide for the sides from the top view.

I need the guides to give me the proper height and width at each station then I need to use them for the loft to guide the shape
Title: Re: German type VIIC or VIIB Uboat
Post by: TomP on November 02, 2016, 09:25:48 PM
Hi Joe, don't know much about American subs but have this drawing of USS Cod are they of any use to you?


(http://i1248.photobucket.com/albums/hh485/tommy3781/2801F966-12D9-4ECF-925B-0D11F514382C_zpshcf579xb.jpg)



(http://i1248.photobucket.com/albums/hh485/tommy3781/47914740-C7C9-4B02-8CD1-69A07609F8BA_zps1nnxzv7r.jpg)
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 02, 2016, 09:47:10 PM
thanks I have shipyard drawings of a few subs but like what you posted the same problem the walkway and ballast bulges on the sides dont show the true shape of the pressurized hull. maybe i am being a little too "xxxxx" but i like to be as accurate as I can because a lot of my projects I do for museums and such so now trying to expand aircraft into boats and subs so that I can widen my work scope
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 03, 2016, 12:53:27 AM
I was just messing around adding the TOO for my Higgins LCVP and it dawned on me maybe I can find the TOO for a sub. I have one for the Pompanito but the stern numbers are all covered with garbage from when the microfilm was copied. so maybe I can find some TOO for it online thats cleaner
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 03, 2016, 05:43:38 AM
i am thinking of scratch building my own steampunk sub then I can have all kinds of cool tubing and gears on the outside etc and not worry about needing to be exact scale though that still wouldnt solve my urge to design a sub accurately
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 03, 2016, 05:17:05 PM
Last night i had got frustrated and had decided that for now just to get me a cool sub designed and not worry abt accuracy. to solve this I had decided to do something I havent seen before (but is probably out there somewhere) and do a Steampunk or Dieselpunk sub. would be cool with all kinds of gears and tubes on it. I still might but last night I had an epiphany and that is I need to trace the top view and profile view, then use those and the  body plan drawings and enlarge them to match the top and profile view at the highest an widest part of the boat. doing this should get me close to the ballpark, and then with so many bulkheads along the length it will naturally give me the shape of the pressure hull. at least that is the theory.

I know  most of this sounds like blubbering nonsense these posts, however there is a method to my madness. by posting my thought processes now as a totally lost noob, maybe others in my same predicament that are also lost but do not want to post admitting it, may learn. also as you just noticed above, by rambling along i may have just found the solution to my problem. I do stuff for the movies, museums, and military bases with my planes so they have to be as accurate as possible, and over the years I got very good at finding the info I needed and drawing them up. So I am very "xxxxx" when it comes to designing as I need it to be almost perfect. I am new to this and having a lot of problems with finding my info and unlike in the plane world not a lot of people share what they have collected, or just that the info isnt out there. so if this works out for my hull design it will be a major milestone for me and i will just have to accept it as the best I can do for now until I can find some sub drawings with tables of offsets for the boat. once I have TOO and decent number of drawings I can just make an excel sheet and import the curve files into my cad program.

so bear with me as i blubber my way into something here soon as this has been mainly my research and learning and once i get going it will become more interesting. in the meantime as I work out the kinks in my theory I think I will do something steampunk and see if I cannot design a sub that will blow people away.
Title: Re: German type VIIC or VIIB Uboat
Post by: unbuiltnautilus on November 03, 2016, 07:05:16 PM
Blubbering away is an entirely acceptable method of designing a model. Certainly much more detailed than my version of CAD, Cardboard Aided Design.
For Steampunk and other Nautilus subs have a look at   http://www.vernianera.com/Nautilus/Catalog/


Many excellent designs on there, plus two of mine %)

Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 04, 2016, 12:20:07 AM
I got the nautilus drawings directly from Disney along with some other info like the real one is only 200 ft not the 300 odd many people do. I drew it up on commission need to rework for radio control but you see too many mine will be unique even thought about the red skull mini sub too will find out tonight when I get home from work and start drawing I have some red stuff from concept art I might mash up either way it will be cool
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 04, 2016, 05:01:18 AM
heres my solidworks version i been working on for the nautilus
Title: Re: German type VIIC or VIIB Uboat
Post by: unbuiltnautilus on November 04, 2016, 08:05:03 AM
Goffs Nautilus is the gold standard of steampunk, even before the term existed. Very nicely done there.
Designing my Nautilus has taken a radically different approach to yours, evolving in stages and currently lurking in a box somewhere as a 22 inch Depron foam mock up. Which from time to time, gets extras glued on or filed off, before being stared at for weeks!
Both design options have their merits, but hats off to your method, most impressive.
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 04, 2016, 05:35:13 PM
well I found the perfect base for my sub looks really cool will make some modifications. will mess with it tonight after work. I worked on blocking it out but need to do some adjustments to get everything correct before I start.
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 06, 2016, 04:30:56 AM
Well tonight started working on a second steampunk design as the first one is going to take a while to get all the proportions figured out. so this one will start with a basic cigar shape then add to it. will be much simpler for me for a first sub.

Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 06, 2016, 04:53:10 AM
Ok here is my loft right now it is 24 sided to give it a cooler look when finished.

ok i have this at 1/64th scale at 400 ft or 75" and 12" diameter. That should give me plenty of room for stuff. I will next be adding top deck and ballast tanks along the side

Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 08, 2016, 07:56:28 AM
Ok so I decided to give a little info on lofting hulls as I know it. Some of you may know this already some may not so will just cover the basics

I have tables of offsets for the Balao class but most are illegible but it will have some numbers that will work for this demo purpose.

first lets have a look at the TOO and explain what we are looking at.
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 08, 2016, 08:07:44 AM
ok there are 3 important bits of info on the TOO

1: frame number = when we convert the TOO for useable data we need to convert the frame numbers. on most ships the length of the ship in inches divided by the number of frames gives you the number of inches between each frame as in ships the stations are equally spaced. Subs are the same, However with ships and subs there are instances where this may not always be true. You will need to look at the lines sheet of the factory drawings to see if it lists any deviation from the norm.

2: Waterline = the top row shows the waterline dimension for each offset this is shown in feet and inches and later will need to be converted to inches.

3: Offsets = for each frame and waterline there is a set of offsets they look like 3-4-5+ or even 3-4-5-
    So what do those numbers mean. they are actually feet-inches-8th of an inch. the + or- means a fudge greater or less when calculating we use 1/16th of an inch which is half an 8th and works out fine in our lofting. so we need to convert the offsets to decimal inches.
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 08, 2016, 08:28:39 AM
Ok so now how do the Tables of Offsets help us.

Well think back to basic geometry class in high school. what we will do is use these dimensions to plot points like on a graph.

the frame dimension tells us how far back from the FP our plot of dots will be. then the waterline tells us the height of our point and the offset tells us how far from the centerline our point will be.

so in the pompanito there are 20 waterlines 1 ft apart. so we will have a series of dimensions to plot us each station.

I use an excel spreadsheet for this. here is a blank example of one of my sheets. the blue area is where my station dimensions will be
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 08, 2016, 08:43:00 AM
ok I will try to add my excel for a Fletcher class destroyer I did so that you can use it as a template and see how I arranged it.

I uploaded it to my website in case you would like to download it and use it for a template and to see how I set it up.

http://www.proflooney.net/FletcherOffsets.rar (http://www.proflooney.net/FletcherOffsets.rar)


Here is a screen shot of how I set the results up so I could copy them and make a txt file so that I could import the txt file or what is called a curve generation table into solidworks and have it generate the correct station shape for me.

(https://i37.servimg.com/u/f37/19/56/48/55/table10.png) (https://servimg.com/view/19564855/14)
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 08, 2016, 08:56:40 AM
for each point we need to list in a separate line in this order (at least for Solidworks) Frame Dimension - Waterline Dimension - Offset Dimension

we do this for each offset listed. if there is no offset for a waterline we do not use it or it will draw a silly line we don't want.

so with the Balao in the middle we will use all 20 waterlines so there should be 20 lines for each table. unfortunately with Solidworks you will need to create a txt file for each station. Some programs like autocad you can use a comma or semicolon at the end of each table (don't know for sure what it is as I don't use autocad) and you can just use 1 txt file to generate all the curves.

Here is an example of my Fletcher class hull once i put all the curve files into it and it generated them. there will be some missing lines to the curves in the pictures but the keel and other parts are separate offsets that at the time of the photos I hadn't added yet.

(https://i37.servimg.com/u/f37/19/56/48/55/hull_010.jpg) (https://servimg.com/view/19564855/15)
(https://i37.servimg.com/u/f37/19/56/48/55/hull_011.jpg) (https://servimg.com/view/19564855/16)
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 08, 2016, 09:12:19 AM
in conclusion not all tables of offsets will be accurate. you may find a weird bulge or inset in your curve. this was common at the shipyards and usually they adjusted their curves at the site and made notes on their floor plans but they didn't get added to the original plans. it is trial and error depending on the size of the bulge, but try adjusting the 8ths of an inch if that doesn't work reset the 8ths and adjust the inches.

the other thing is that there are several lines in the table you will have to figure out which line is the bad one. once you play around a few times you will get to knowing about which line the problem lies. and be sure once you fix the error to adjust it also in your excel file and save it so if you share it or redraw later you wont have to mess around.

I hope this helps people understand a little more about tables of offsets and maybe people have some in their reference along with the hull lines from factory drawings and wouldn't mind sharing with the rest of us and we can maybe come up with a series of excel files so people can more easily design some subs.

BTW sometimes tables of offsets are called lofting tables
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 10, 2016, 05:54:05 AM
Well couple days ago i came across some fairly decent drawings for a German type VIID Minlayer sub. it has 5 banks of 3 mines on it and is something usually not done as most do the B or C model.

so looking them over and doing my research I have been doing I think I can possibly get this thing lofted up so will give it a try while i take a break from the steam punk sub so i can get some ideas for it as i got the outlines figured out but didnt figure any more on the design yet.

yesterday I got the top view traced and now i am home from work and off tomorrow will try to get the profile view traced then I can start working the loft.

so ifn I can get this lofted up this one will be 72" as a prototype boat I want to do a 1/32 scale which would be 94.875"
one thing i need to figure out is how I can split the sub in the middle to have a front and rear half for easier transport.

now for the items I want to have on the sub (some may not be feasible as this first sub so not sure what can and cannot be done)

1: working periscope
2: dunno which type ballast system is best yet still researching
3: front and rear firing torpedos
4: launchable Mines in a sequence not to have them all just pop out at one time
5: Possibly on the larger version moveable deck gun and possibly firing 22 blanks

will post pictures soon as everything is traced

since these drawings seem to show the pressure hull outlines to a point it may help me figure out how to draw the Balao. I need to get into the Balao drawings deeper as they may have offsets listed somewhere for the pressure hull top and bottom guide lines.

finally seems the more I play around bouncing along different types of subs I am learning more and more to where soon I hope to be able to draw up many different types of subs. I do have a future project as I found a really nice solidworks model of a deep sea rescue sub, so it will just be getting the parts made to kit it up.
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 12, 2016, 12:45:53 AM
thanks i been there havent joined yet but I did work on a nuke sub like I said they are bland and boring looking but it will be something to start with to get the internals and WTC understanding going. like said have to do the designing solo as havent found ppl really into scratch designing to learn from. there is one site that mentioned some sub designing guru I have messaged him with a couple rookie questions but no response in a couple weeks.
here are a couple picks. I work the next 4 days in a row but will be working on the framing etc. will be approx 1/96 scale at 72" long

Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 15, 2016, 02:41:22 AM
well guys been silent for a few days I was studying plans for michael Bays new transformers movie there is a manned submersible in it and we  are bidding on the job to make the filming model so I was busy figuring costs, and design time,  machining time, building time, etc to reach the deadline.

due to certain issues that I cant share certain photos I can post one that isnt stamped private the rest are secret files which basically show detailed drawings and other stuff film doesnt want in public yet
Title: Re: German type VIIC or VIIB Uboat
Post by: JosephHuntley on November 20, 2016, 03:18:47 AM
well with the holidays been putting in overtime at work so not much chance to do a lot. however I have created an excel file for the Balao TOO and been putting them in. the offsets are a real PIA to read but I got  stations 70-137 entered now am going to guess at 1-70 stations since that sheet is really horrible to read.
 
 I also am still setting up the formulas for conversions and most of them are complete, and the second sheet which has the tables with all the final results for importing into cad to generate the stations is going well. the biggest hurdle of all is trying to just read the offsets. wished i had better tables like I had when I did my fletcher Hull but these were the only ones i could find and that was the ones from the Pompanito Museum site. hoping by maybe next weekend having a few of the curves generated in solidworks. If I can get several of the 1-70 lines generated mainly in the bow area I will be able to loft up the pressure hull decently