The Ship Model Forum

The Ship Modelers Source
It is currently Wed Aug 05, 2020 5:23 pm

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 4311 posts ]  Go to page Previous  1 ... 209, 210, 211, 212, 213, 214, 215, 216  Next
Author Message
PostPosted: Sat Mar 07, 2020 11:30 am 
Offline
User avatar

Joined: Mon Jan 10, 2005 1:21 pm
Posts: 3204
Location: equidistant to everywhere
It has been pointed out that ship builders from different countries have different traditions regarding how much of the ship is calculated in detail ahead of time and how much is extemporized during the construction. For example, in the decade prior to WWI, apparently the Russians calculated and sketched everything in detail, and the shipyards were not suppose to improvise. When the Russians solicited proposals for ships to be built in Britain, the russian admiralty were astonished so much of the British design were expected to be fleshed out as the ship was actually built.

_________________
Assessing the impact of new area rug under modeling table.


Top
 Profile  
Reply with quote  
PostPosted: Sat Mar 07, 2020 11:51 am 
Offline

Joined: Sat Jan 17, 2009 2:12 pm
Posts: 2561
then what happened with the Ford & it's ammo elevators?


Top
 Profile  
Reply with quote  
PostPosted: Sat Mar 07, 2020 12:00 pm 
Offline

Joined: Wed Jan 02, 2013 1:15 am
Posts: 2249
The Boeing 777 was the first large aircraft designed without mockups. The computer claimed that a mechanic could "get to everything". Of course you might have to have one arm 6" longer than the other and a hand on backwards, or train a chimp to do it.


Top
 Profile  
Reply with quote  
PostPosted: Sat Mar 07, 2020 1:50 pm 
Offline
User avatar

Joined: Mon Nov 18, 2013 3:41 pm
Posts: 1690
Location: Mocksville, NC
David P wrote:
Quote:
then what happened with the Ford & it's ammo elevators?

Well, that occurs when you allow private industry to dictate the terms of building/design contracts where they bear very little of the actual R&D costs PRIOR TO the actual construction of the contracted item and promise to develop the necessary engineering/design as it evolves - and always at the public's expense. But how can it change when so many of those in Congress who approve these policies are in bed with industry to begin with?

Go back and look at the history of development of fighter planes in the 1920's/30's/40's and you'll see that all aircraft manufacturers had to bear the R&D costs themselves and actually produce a working version of their design before production contracts were awarded.

IMHO, this is just more of "the swamp" that needs to be drained before we can get back to sensible and reliable engineering/design and construction of any commercial/military equipment and have confidence we are getting a worthwhile and functioning product at a reasonable price. Does the 737 MAX ring a bell??? :doh_1:

_________________
HMS III
Mocksville, NC
BB62 vet 68-69

Builder's yard:
USS PENNSYLVANIA (BB-38) Late '40 1:200
USS STODDARD (DD-566) 66-68 1:144
Finished:
USS NEW JERSEY (BB-62) 67-69 1:200
USN Sloop/Ship PEACOCK (1813) 1:48
ROYAL CAROLINE (1748) 1:47
AVS (1768) 1:48


Top
 Profile  
Reply with quote  
PostPosted: Sat Mar 07, 2020 2:18 pm 
Offline

Joined: Sat Jan 17, 2009 2:12 pm
Posts: 2561
no disrespect for the people who died but don't you mean Boeing's "Flying Auger"?


Top
 Profile  
Reply with quote  
PostPosted: Sat Mar 07, 2020 2:23 pm 
Online
User avatar

Joined: Mon Jan 10, 2005 6:00 pm
Posts: 11173
Location: Calgary, AB/Surrey, B.C., Canada
Folks, please try to keep it on topic - this thread is big enough as it is!

_________________
De quoi s'agit-il?


Top
 Profile  
Reply with quote  
PostPosted: Sun Mar 08, 2020 9:17 pm 
Offline

Joined: Thu Jan 22, 2015 9:27 pm
Posts: 19
Location: Winnipeg, Manitoba; Canada
Gentlemen, I just want to/have to say THANKS for having this conversation in the first place.

To see these talks and allowing us to gain some insight as to 'what went on' and "how'd they do that" is incredible. Much appreciated, and please,,,,, carry on!


Top
 Profile  
Reply with quote  
PostPosted: Mon Mar 09, 2020 5:21 pm 
Offline

Joined: Sun Jun 10, 2012 9:07 pm
Posts: 325
The hull internal structure is made up of several elements. There are three main types:

1. vertical longitudinal members (keel longitudinals)
2. horizontal longitudinal members (stringers, breasthooks, and you might include decks)
3. transverse members (frames, beams, floors)

It is hard to keep track of things because one type of member can be composed of subcomponents and members can flow into a different type of member.

A frame can include floors (the part under the deck) and beams but beams and floors do not have to be part of a frame.

Stringers flow into breasthooks and torpedo bulkheads. So part of a torpedo bulkhead could be called a stringer.

Furthermore, the members are not solid structures. Support structures flow and intersect in three dimension so many members have to be intercostal. The general rule is that vertical longitudinal members take precedence over transverse members that take place of horizontal longitudinal members.

Unlike a model ship, the hull shell was built first and the structural members were erected behind the shell. The shell was largely, if not entirely, self supporting.

Here is an image showing the underlying structure going by what the plans call things. The frames are in red. Note that the framing stops at the third deck within the citadel. There are webs at some frame locations that effectively extend the frames up to the second or main deck. Some of these have beams that go all the way across creating a full height frame. However, many of the frames do not have extensions above the third deck in this area. Apparently, the designers were relying on the stiffness and strength of the side armor for support here.


Attachment:
NJ Interior.jpg
NJ Interior.jpg [ 96.88 KiB | Viewed 688 times ]


Top
 Profile  
Reply with quote  
PostPosted: Mon Mar 09, 2020 9:15 pm 
Offline
User avatar

Joined: Mon Jan 10, 2005 1:21 pm
Posts: 3204
Location: equidistant to everywhere
I’ve never seen any indication the shell of a battleship can be self supporting in large part. Instead piece of it small enough to be self supporting are erected, then structure behind it are added to provide it with support and stiffness, and provide the strength to withstand the weight of addition structure, the more shell is erected around the first piece.

_________________
Assessing the impact of new area rug under modeling table.


Top
 Profile  
Reply with quote  
PostPosted: Mon Mar 09, 2020 10:47 pm 
Offline

Joined: Wed Jan 02, 2013 1:15 am
Posts: 2249
Here is a photo of Iowa: Plates are starting to wrap up from the bottom. Note scaffolding, probably to facilitate riveting.

Attachment:
Iowa.jpg
Iowa.jpg [ 306.6 KiB | Viewed 658 times ]


Top
 Profile  
Reply with quote  
PostPosted: Tue Mar 10, 2020 1:21 am 
Offline
User avatar

Joined: Mon Jan 10, 2005 1:21 pm
Posts: 3204
Location: equidistant to everywhere
Yes, but before those side plating get very high, the interior of the double or triple bottom, the bulkheads, the side protection system, and the decks in the lower part of the ship would all be put in. I don’t think you will find many instances where the shell platings rose much more than 1 deck above the highest deck that’s been installed inside it. Also, the framing for the side plating is usually installed before the framing. You often see side frames sticking up above the highest strake of side plating installed.

Note while the scaffolding was erected up to near main deck level early on, not much of the actual shell plating is erected above the highest interior deck that’s been installed:

http://navsource.org/archives/01/061/016162a.jpg

http://navsource.org/archives/01/061/016162e.jpg

_________________
Assessing the impact of new area rug under modeling table.


Top
 Profile  
Reply with quote  
PostPosted: Tue Mar 10, 2020 12:48 pm 
Offline

Joined: Wed Jan 02, 2013 1:15 am
Posts: 2249
My WAG is that it's easier to get the frames to fit the shell plating than get the shell plating to fit the ribs.


Top
 Profile  
Reply with quote  
PostPosted: Tue Mar 10, 2020 11:02 pm 
Offline

Joined: Sun Jun 10, 2012 9:07 pm
Posts: 325
Here's one of the Iowa. The hull plating at the side is nearly to the 3d deck and has no framing. Framing is being attached at the bow but notice the frames are not supporting anything. The internal structured added stiffness but did not hold the shell together.

The highest priority in construction was the machinery spaces. The transverse bulkheads in that area were erected as soon as the the shell was wide enough to accommodate them and the holding bulkhead was added to the side.

Pictures show the machinery spaces up to the third deck before the bow was ever started.

In some cases the shell was way ahead of the rest of the ship in the vicinity. In others, it was at the same pace.



Attachment:
Iowa.jpg
Iowa.jpg [ 337.15 KiB | Viewed 578 times ]


Last edited by bigjimslade on Wed Mar 11, 2020 3:42 pm, edited 1 time in total.

Top
 Profile  
Reply with quote  
PostPosted: Wed Mar 11, 2020 3:03 pm 
Offline
User avatar

Joined: Mon Jan 10, 2005 1:21 pm
Posts: 3204
Location: equidistant to everywhere
But is the scaffolding holding up the shell plating?

_________________
Assessing the impact of new area rug under modeling table.


Top
 Profile  
Reply with quote  
PostPosted: Wed Mar 11, 2020 4:29 pm 
Offline

Joined: Wed Jan 02, 2013 1:15 am
Posts: 2249
I don't think so, as the ship was riveted (mostly) somebody has to work on both sides. I wonder if some of the seemingly strange jointing and lapping had to do with this construction method?


Top
 Profile  
Reply with quote  
PostPosted: Fri Mar 13, 2020 10:59 am 
Offline

Joined: Sun Jun 10, 2012 9:07 pm
Posts: 325
Fliger747 wrote:
I wonder if some of the seemingly strange jointing and lapping had to do with this construction method?


Without computers, it would be effectively impossible to design frames for the hull shell that could take into account the myriad of joints and joint types as well as different plate thicknesses. Even with a computer, it would be impracticable to design such frames while taking into account the amount of error that would occur in normal construction. A single frame can have more than 60 notches cut into to it for joints. Multiply the margin error by sixty and one can see the problem frame and bulkhead construction would create.

Instead the hull served as the template for cutting the frames. The system of construction was backwards from that used in the age of sail.

If the hull plating were flush and welded, the weld gaps provide sufficient tolerance for small deviations.


Top
 Profile  
Reply with quote  
 Post subject: The Rudders and Riveting
PostPosted: Sat Mar 14, 2020 11:38 am 
Offline

Joined: Sun Jun 10, 2012 9:07 pm
Posts: 325
Here is a structural detail that did not make it into the recent book. The lower part will be familiar but the upper part may not. This is the forging for transmitting the force of the rudder to the ship.

The rectangular area forms part of the ship's hull. At the center rectangle is its 2-1/2" thick. It was machined so that it is 1-1/2" at the middle rectangle and 1-1/8" at the edge. It is actually 4 plates. Draw lines from the outer corners to the inner corners and extend them to the center to get the cut lines.

The diagonal line shown going through each plate marks the limit of the half siding where the hull bottom is flat in cross section.

The cones at the top poke up through the first platform where the rudder machinery is located. Frames and longitudinals pass over the plate and join the central forging. The horizontal structure with moon curves supports them at their ends.

The entire assembly was welded and welded to its neighboring plates.

This an example that refutes the idea that that hull is riveted because the designers did not trust welding. In fact, the key structural parts of the hull shell are welded.

It also illustrates some of the labor-intensive construction that went into the ships. Take a 2-1/2" plate. Bend it to shape. Machine it in steps down to 1-1/8. Weld it in place. Then machine the edges to match the thiner plates surrounding it.
That's a lot of work.

I guess the $1000 toilet seat is nothing new in defense projects.

Attachment:
Rudder Bearing V2 02.jpg
Rudder Bearing V2 02.jpg [ 83.22 KiB | Viewed 405 times ]


Top
 Profile  
Reply with quote  
PostPosted: Sat Mar 14, 2020 8:32 pm 
Offline

Joined: Sun Jun 10, 2012 9:07 pm
Posts: 325
Here's a plan that I found that may be of use to modelers. It is for asbestos mats on bridge decks. Someone had asked about the deck covering previously. I have no idea of what the color would be. The asbestos mats we used in chemistry were white.

This the highest resolution I can post here.

Attachment:
1403AP uF Asbestos Mats on Bridge.jpg
1403AP uF Asbestos Mats on Bridge.jpg [ 337.86 KiB | Viewed 365 times ]


Top
 Profile  
Reply with quote  
PostPosted: Sun Mar 15, 2020 9:58 am 
Offline
User avatar

Joined: Mon Jan 10, 2005 1:21 pm
Posts: 3204
Location: equidistant to everywhere
bigjimslade wrote:
Here is a structural detail that did not make it into the recent book. The lower part will be familiar but the upper part may not. This is the forging for transmitting the force of the rudder to the ship.

The rectangular area forms part of the ship's hull. At the center rectangle is its 2-1/2" thick. It was machined so that it is 1-1/2" at the middle rectangle and 1-1/8" at the edge. It is actually 4 plates. Draw lines from the outer corners to the inner corners and extend them to the center to get the cut lines.

The diagonal line shown going through each plate marks the limit of the half siding where the hull bottom is flat in cross section.

The cones at the top poke up through the first platform where the rudder machinery is located. Frames and longitudinals pass over the plate and join the central forging. The horizontal structure with moon curves supports them at their ends.

The entire assembly was welded and welded to its neighboring plates.

This an example that refutes the idea that that hull is riveted because the designers did not trust welding. In fact, the key structural parts of the hull shell are welded.

It also illustrates some of the labor-intensive construction that went into the ships. Take a 2-1/2" plate. Bend it to shape. Machine it in steps down to 1-1/8. Weld it in place. Then machine the edges to match the thiner plates surrounding it.
That's a lot of work.

I guess the $1000 toilet seat is nothing new in defense projects.

Attachment:
Rudder Bearing V2 02.jpg



That doesn’t refute it at all. Whether a hull structure is key does not say whether it is expected to be highly stressed either with normal or shock load in service, or whether the joints are expected to flex or deform.

We know even the Germans, who accepted welding much earlier, and to a much higher degree, than the US or anyone else for large warship construction, welded the entire hull of the bismarck class everywhere but the torpedo defence system because the bulkheads there were expected to see the highest shock loads and greatest deformation anywhere in the hull. They trusted welding around the rudder but didn’t trust welding where stress is really high

In a capitalship the strength deck, bottom and the strokes of hull side shell strakes close to them between end turrets experience the greatest load in rough sea, while the torpedo defence system expthe greatest deformation. So on the Iowa these were all riveted.

_________________
Assessing the impact of new area rug under modeling table.


Top
 Profile  
Reply with quote  
PostPosted: Sun Mar 15, 2020 12:08 pm 
Offline

Joined: Wed Jan 02, 2013 1:15 am
Posts: 2249
Several German Capital ships had their stern sections cleanly fall off due to damage. I believe even Bismarck ended up on the sea floor minus her stern section.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 4311 posts ]  Go to page Previous  1 ... 209, 210, 211, 212, 213, 214, 215, 216  Next

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 7 guests


You can post new topics in this forum
You can reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group