Let's say you want to build a 20ft. modern submarine out of wood....

I would start by looking at the way a balsa fuselage is put together for an RC plane.  Formers, stringers and sheeting to cover.

Buckets, tubes, planter pots, paper mache

I don't believe I would try something like that....

I'd start by buying a house with a 2-car garage...

No, three car garage....

LOL the way you worded it, it reminds me of a crazy sales pitch you would hear in a comedy, something you would say with a "you are going to think im crazy, but just go with me on this" look lol . i saw a thread somewhere online, cant remember where though, of a man who did something similar.... he built a 1:1 Tiger 1 turret out of wood..... perhaps finding the thread (Google should help) would offer you a good idea of where to start?

You build a model ship hull by finding cross sections for specific sections of the hull. You will need quite a few of them, the more the better. They are placed on a keel of some sort. This will kind of look like a snake skeleton with the keel being the spine and the hull cross sections as ribs. You will then fill between the sections with something, foam perhaps. And then carve away everything until your foam matches nicely to the cross sections. Hope this made sense

Chris

I agree with someone else who said make it like an RC airplane, only NOT out of balsa.  That thing will have so much buoyancy anyway that you should use hardwood- even so you'd need a ton (literally) of ballast.  If you want a modern sub, I'd make it out of a piece of the largest sewer pipe you can find. For an older sub, you need a fancier structure, with ribs, longerons and sheeting. You'd need a very big lathe for some of the lathe work you'd need.  And of course a very large trailer to take it to the lake.

and also, i recall a documentary on Pearl Harbor, where they were testing a picture to see what was in the water near battleship row by building a scale midget sub and placing it in a lake roughly scale to Pearl, took pictures from the scale distance, etc, etc to test the the whole "did a midget sub really make it into Pearl" thing, they build a scale midget sub that was close to 15-20 feet, and covered the build pretty good if i remember right.... if you  can dig that up it may help too.

Don,

That size "sewer pipe" can get pretty spendy, pretty fast.  For a 20' hull, you'd be looking at about a 36" dia pipe to get close to an LA class SSN.  What you might find in that size would be HDPE, most of which is corrugated.  You  can get some smooth wall, though.   www.plasticpipe.org/.../high_density_polyethylene_pipe_systems.pdf

Sanitary lines usually are ASTM 3034 PVC, and are mostly under 15".  HDPE is used for storm systems, and in the last 10 years has pretty much replaced Corrugated Metal Pipe (CMP) or RCP (Reinforced Concrete) due to cost & ease of installation.

HTH,

Reid

TheWildChild

and also, i recall a documentary on Pearl Harbor, where they were testing a picture to see what was in the water near battleship row by building a scale midget sub and placing it in a lake roughly scale to Pearl, took pictures from the scale distance, etc, etc to test the the whole "did a midget sub really make it into Pearl" thing, they build a scale midget sub that was close to 15-20 feet, and covered the build pretty good if i remember right.... if you  can dig that up it may help too.

I saw that too....I think it was one the Military Channel...

You could probably use OSB board for the formers, and 2x2's for the stringers.

For the covering.....aluminum???????? 

In a chapter of "Building Model Warships of the Iron and Steel Eras" edited by Peter Beisheim,  Stephen Henninger describes his scratchbuild of the 12-foot long (1:100) scale USS Enterprise CVAN-65 which is now on display at the Smithsonian's Air & Space Museum.

He used particleboard (chipboard) for the keel and frames and skinned the hull with 1/16 birch plywood.

He chose the particleboard because it was economical, stable, strong, and available worldwide.   He built three halves of the hull while he was deployed by NASA to ground tracking stations in South America and Africa.   He completed the first half during and following his first assignment then packed it away when he went on his second.   He finished the aft half, then with more time on station and nothing to do he rebuild the forward half.   When he was returning home he had to further break the hull into three-foot sections to fit into space available in the shipping container for his other household goods.

He describes using 10 4'x8' sheets of 1/2-inch particle board to make the frames of the first two halves and dulling several bandsaw blades during the seven day process.  The frames were aligned on a steel rod at a spacing of 2.83 inches and faired by eye.

Surely you remember, right next to the ads for Sea Monkeys...

Hey " G "

    Is that you in the sub ? Yeah , I remember those things .If you remember there was for a while on one of the pages nearby an ad for your own spaceship too .Pretty much the same idea !  T.B.

At one time I thought of doing an 18-20 foot Gato for a couple of lakes around here......would have rattled the bejeepers out of the fishermen trolling to surface alongside.....  Just way to involved for my abilities, even to do a surface only version.

Winetanker

 

 

TheWildChild

and also, i recall a documentary on Pearl Harbor, where they were testing a picture to see what was in the water near battleship row by building a scale midget sub and placing it in a lake roughly scale to Pearl, took pictures from the scale distance, etc, etc to test the the whole "did a midget sub really make it into Pearl" thing, they build a scale midget sub that was close to 15-20 feet, and covered the build pretty good if i remember right.... if you  can dig that up it may help too.

 

 

 

 

 

I saw that too....I think it was one the Military Channel...

You could probably use OSB board for the formers, and 2x2's for the stringers.

For the covering.....aluminum???????? 

 

Mysteries of Pearl Harbor was the name of the show.

I had started working on a sub as a basis for a ROV and another one to haul things to an island in the river that I go swiming in (for sodas and snacks and other things I didn't want to get wet). Built a rib and stringer frame, foam between the ribs, sanded until it was shapped, then covered in fiberglass. After lots of filler, sanding and painting I had my subs.

Well;

   Talk about teasing boaters , try to imagine this ,0630 am . Nice green metallic bassboat , two fishermen . Made a hell of a wake in a no wake zone to get where they were . Along comes a Flower Class 1/72 scale Corvette .

   Fitted with trainable fire nozzles that worked . Surprised , getting shot by water from a model boat .You can bet they were ! Moved away from there slowly , constantly being harassed by these little water nozzles on this little boat . Tried to ram it twice , No Dice ! , and never came back either .        T.B.