Evolution of a U.S. Fleet Boat Conning Tower, 1:24

[Guest]

Ever since I was a youngster, I've been fascinated ..., no, addicted, to submarines; I used to watch the Silent Service television program religiously every Sunday in the 1950's. I've wanted to build a sub project ever since. I've been re-watching Destination Tokyo too many times lately, and decided I just had to start building a conning tower.

I'm not sure where this is going to go in the long run; perhaps this will stand alone, or perhaps it will have a cut-away fairwater to view the inside of the tower, I don't know yet, the project will just grow!

I started with a suitable 4" coffee container:



I have worked out a basic deck and periscope positions; there will only be one eyepiece in the tower, as in the Sargo/Seadragon/Tambor classes. Here is an overview, with one periscope shear standing up from the forward scope housing:



A closer view, with after periscope well installed:



A close up on the after periscope well (a piece of 5/8in K&S telescoping tube, with a rim-band of 21/32in tube adhered with CA (I prefer soldering, but we're not supposed to play with torches or open flame in my "senior citizen" apartments!)):



Here is a view of the deck, one shear before painting, and one experimental, prototype periscope; I learned a lot from making the proto (detailing is going to be tricky at this scale; I'm disappointed that I won't be able to make the handles fold up!); the finished article will be more like 18in or so in length, and, if I can afford it, I may make the main body of K&S tube, provided the local vendor has the longer pieces:



We shall see where this takes me ...

Regards, Johnpipe

[geegad]

Lookin forward to seein this coming along a do like a scratch build food luckGeegad

[Guest]

Well, I have reached the stage of beginning the visualization and mock-up of the bridge-deck. 1942 measure, with the covered navigation-bridge intact, and the fairwater cut down astern for the 20mm Oerlikon gun. First pix is the initial mock-up:



Studying this, I realized I needed a riser for the after periscope (Shiny bits! Woo Hoo!), giving the distinctive two-step look of the Sargo through Tambor classes:



And, of course, the forward periscope needs a housing from the shear to the control-room, complete with control-room head (K&S tubing as usual):



I'm considering building the control-room below, as a horizontal half-hull. And, they should get the men in the white coats to take me away before it's too late, as I have this delusion that I can make the periscope with folding handles, and motorize it to go up and down!

regards, Johnpipe

[Guest]

This is certainly looking like a very interesting project and a great excercise in scratchbuilding. Do you have an idea of scale or are you simply making what looks right?

I love the way you are not supposed to use open flames, I 'm surprised they allow you to use knives!!

[geegad]

Keep it coming!!! At least you've got the weather to build outside In sunny California

John

[Guest]

As mentioned in the title, the scale is 1:24. Some detail info is available from the C. & R.'s Spearfish modification plans from hnsa.org Making a little progress, some of the first framing and glue-up:



I made some formers; only the fore-end is glued to the frames, the after end is tacked temporarily with tape, as is the experimental decking.



Added the bridge-hatchway; temporary trunk, and hatch-lid to be done up:



Here is a look into the tower with the new number-two periscope (which is still under construction):



Will get the periscope pix up next.

[Guest]

Got started on the brass periscope; several layers of telescoping tube to join the square-end to the 5/16in main tube, compared with the prototype:



A little detail, the eyepiece filter panel:



Set up the top taper stack; not glued-up yet, but will be turned and filed once glued:



Here's a long view, the top stack will plug into the main tube:



I'm working on making folding handles, but am missing my smallest drill bits needed to make the hinge-points; I may not succeed on these, but I'm having a go!

Regards, Johnpipe

[Guest]

A Word on Submarine Construction ...

U.S. Fleet subs were built, not to plan, but to specification. As a result, details and appearance would vary, depending on which yard built the boat. Government yards at Portsmouth and Mare Island built many of the fleet boats, and Electric Boat Co. (now a subsidiary of General Dynamics) built most of the rest (a few were built by a company that took over the name of the defunct Cramp shipbuilding Co.). Usually the build designs are referred to as Portsmouth or Electric Boat; Cramp was a follow-yard to Electric Boat plans.

Unusually, the Spearfish, SS-190 built by EB, has the Salmon-class internal layout, with the galley and crew's mess in the same compartment as the control-room, whereas Portsmouth Sargo-class builds moved the after-bulkhead forward, putting the galley and mess in the after battery compartment, which became the standard layout, with the central compartment between bulkheads being only the control room, where the radio-room was located (radio-room was in the forward battery in the EB builds).

Whereas the Sargo, Seadragon and Tambor classes had the split-level periscopes as built, this was changed during wartime modifications to the standard arrangement with both eyepieces in the conning tower.

This model will be based on the pre-war arrangements and equipment of this class. Exact fabrication is going to be a mix of what I can duplicate from available actual details, and what "feels right" for what I can't get reasonable details for, or for what doesn't work well in model-building. Some parts simply don't have drawings or photos available, and will have to be improvised.

regards, Johnpipe

[Guest]

Got a little more done today; cut out for the control-room hatchway, and had to make a jig to guide the Forstner bit:



Here's a view looking down the bridge-hatchway into the control-room hatchway:



Here's a side-view:



I cut off the temporary bracket on the stern, and put up some proper angle-brackets, complete with token lightening holes:



And gussied up the stern-former, and glued and clamped in place (ran out of CA several days ago, and falling back on good old Titebond II wood glue):



The clamp is actually repairing a recalcitrant CA joint that failed!

I am in process of re-sawing some old furniture poplar to make decking strips; no money left at end of month for store-bought goodies, so re-cycle comes to the rescue. I still need to get to the art store to find some card-stock for the plating.

regards, Johnpipe

[Guest]

Got all the decking put down, and sanded:



This required some corrective surgery, and addition of risers. I made mistakes by starting the project based on photo interpretation and Portsmouth builds, but the hull below is going to be Electric Boat. And, it's going to become a 3/4 hull. I even have a potential offer of .020 steel shim stock for the external plating!

Got the bridge hatch trunk roughed out; it will be profiled more closely before it's fixed in place:



Uncanny, but by both intuition and accident, the hatch-trunk ended up exactly centered relative to the tower axis, according the to C&R plans!

At this point, I need to make the concave tower end, and the steering-gear for tower and bridge. Then comes the 20mm Oerlikon at some point.

Regards, Johnpipe

[Guest]

I started a paper-pattern for the fairwater, using 0.018" card-stock (this thickness is equivalent to 7/16" at scale).



Made up a surface steering-pedestal, and the extension from the tower steering-gear (can't find any good images on these; only vague sketches in the plans).



I have started the central compartment, Electric Boat style, with the galley and crew's mess in the central compartment, along with the control-room.



The character is too large for scale, he's about 8ft. in this context.

I am still searching for information on the configuration for the lower lid of the conning-tower; on these early boats, the lid is two feet (approximately) below the tower floor, in a sort of "tub," whereas new construction moved the tower lower, and changed the hatch style (still has a "tub" but shallower).

That's all for today, the model slowly evolves!

Regards, Johnpipe

[Guest]

The lower bulkheads for the hold have been added; stiffeners from the Balao plans are adapted:



This is the forward bulkhead of the control room:



I started tackling the galley; here are shelves and a stainless steel sink (actually craft-tin), with plumbing by K&S:



Here's a view of the "plumbing" under-sink:



I have received info on the conning tower lower lid; according to my informant, the early boats had a 21 x 29 inch lower lid! Depending on the hinge axle size, I may be able to start on that detail now, as I may have the .047-inch drill for the 3/64" brass rod.

Portents of things to come; trying out potential hull-covering:



The particular card stock is 140#, and is equivalent to only 7/16 inch; the Sargo class had a hull of about 11/16in.

I still plan on using 1/16" basswood for the fairwater, as it's easier to work all the details with. I will inquire with the art supply whether any heavier and suitable card-stock is available, else I still may use basswood for the hull. The boats have cork linings, and I can get suitable cork from the auto supply (used for gaskets).

More to come ...

regards, John

[Guest]

One of the difficulties of making an internal model of a fleet submarine is the fact that the main pressure hulls were externally framed; this means that traditional planking construction cannot be used for the hull. This being the case, the model has to be built without a hull, then the hull wrapped afterward. This means that support for decking in the model must be invented. I used stringers, as shown here:



I added a drain and strainer to the galley sink; I measured my home sink for depth and drain size (standard drain-strainer 3") and said to myself "12 divide 3 equals 4, so 1/4" equals 3"! That's true in 1:12, but unfortunately this is 1:24, which means my hard work produced a drain with a 6" strainer! Oh well, it wouldn't be one of my models if it didn't have mistakes!



The original tower steering extension was dry-rotted! I replaced it with a new one turned from nicely mineralized yellow poplar, which looks so nice I've Johnson's waxed it and left it natural.



Here's the new glue-up; I had to remove the surface-steering station to re-position it with the new tower pedestal. The wires line up the parts orientation.



I really need to make arrangements for a trip to visit the Pampanito in San Francisco; I'm going to need to take a few pix and make a few measurements in order to finish this compartment. I think I may have to write to Electric Boat to resolve the issues of the conning-tower lower-lid.

Later ...

regards, John

[geegad]

Simply amazing it's in a different world to the models i make keep it coming You doing a cracking jobGeegad

[Guest]

Without proper plans, the level of error increases! I missed the scuttlebut, which changes the dimensions around it, so a major tear-down and re-build of the starboard partition was in order:



A closer-in look at the "scuttlebut" (submarine name for the drinking fountain), at least where the fountain will live:



I had to modify the after storage locker, which was a little short; front view, with new partitions for the coffee station, scullery, etc, standing by:



Since in this case it was too much trouble to tear away what was already there, I simply added a false wall to gain the proper foot-print:



This may look similar to the above, but it is actually the Fresh Water tanks, looking at the un-finished side:



Here is the center section, with wood panel but before attaching the tin with double-stick (carpet-type) tape:



Here is the other side, clamped up, as I had used a cement to attach the tin:



I found an old, experimental poplar tube, partially turned, that spoke to me and said "here's the gyro compass;" it was correct, there was a gyro-compass hidden inside:



I still need to get some decent plastic to make the top cover (the gyro-compasses I've seen have a transparent lid).

Still trying to find sub- 1/16" fractional drills, or number drill equivalents in #66 & #67, which are not part of the general hardware store stock; I don't want to have to order from McMaster-Carr online, as one needs to work up a decent size order to justify the post and handling. I need them to be able to do the metalwork on the periscope handles and the hatch-hardware.

Still trying to find the dimensions on the tower lower-hatch surround.

regards, John