I'm interested in model submarines and looking for advice..

[scottyk]

Hey guys I am obviously a new guy here to the forum and I am interested in getting into RC submarines. I am a experienced modeler with experience ranging from racing RC cars, machining and casting my own parts for model steam engines, autonomous drones, brushless and lipos, I even 3d printed my own working RC snowblower. I have messed with alot of areas of this hobby and have alot of the tools needed such as a mill, lathe, 3d printer, silver soldering supplies, TIG welding, casting metals etc... I also have enough experience to realize how complicated things can get in a hurry so in the interest of saving me months of failed experiments I figured I would come here and ask the experts!

With that being said, I feel like a simple dynamic diving submarine would not be the excitement I am after in a sub, so I am interested in a static diving model I could run in a larger pool or open water. I would have access to a swimming pool with a underwater observation window a few times a year, so assuming a FM radio would penetrate the window and water I think this would be a great place to run a sub along with the local boating spots.

I am not a "submarine enthusiast" so the scale accuracy is not a big deal, I do however like the looks of older U-boats when compared to the round shape of the newer nuclear style submarines. I am not looking for a very long term project, something I could build in a month or 2 would be nice.

Thanks! Scott K

[eckloss]

Here is a must-read for beginners: http://www.subcommittee.com/scr/subs...stevesbook.pdf

[subdude]

Scott,

Welcome to the dark side! May I suggest that you post your location, as there may well be someone local to you who could be of assistance. And if you can be in central Indiana in a couple weeks, the fun run in Carmel will have many interesting subs there, along with owners who are happy to talk about them and share information.

Jim

[salmon]

Scott,
Welcome aboard!
This is, IMHO, the best hobby and it sounds like you have a great venue to run it in.
If you find a used Thunder Tiger Neptune SB-1, you can be up running real quick. There are some buying the New Engel Akula II https://www.engel-modellbau.eu/catal...t4via86rdia557 and some are putting it together in less than 7 days (some wizards have it down to two days) others several weeks. It is an all inclusive kit (minus TX and RX).
If you are on the west coast, and not able to go to Indiana, there are two meets one is in LA and the other in San Francisco. As Jim said, let us know where you live.
As a side note, you will find that the people on this forum are passionate about the hobby and incredibly helpful.
Peace,
Tom

[scottyk]

That is a good point subdude, I am located in Cedar Rapids Iowa. I have been doing a decent amount of research in the last 2-3 weeks and ran across that publication posted on this thread "steves book" and that is a very well detailed tutorial I must say! I have completed and are still working on projects that take years to complete these are mostly steam engines built from raw castings. This is what I am trying to avoid, and I am being brutally honest here when I say I just dont want to jump TOO deep with a long term project that could end up on the shelf waiting for me to have time to complete it, so the level of scratch building in that tutorial is what I am trying to avoid.

I have heard good things about Nautilus Drydocks products and service, do you guys think their starter kits such as a Revell Gato in 1:72 would take longer than a couple months to complete the build portion? I was under the impression the entire WTC came assembled and tested, I realize I would have to complete my own tests and trimming/tuning but thats part of the fun and excitement and I dont really include that in the "build" portion of it. I am not trying to ignore or discard your guys advice just trying to get a idea here.

[scottyk]

Scott,
Welcome aboard!
This is, IMHO, the best hobby and it sounds like you have a great venue to run it in.
If you find a used Thunder Tiger Neptune SB-1, you can be up running real quick. There are some buying the New Engel Akula II https://www.engel-modellbau.eu/catal...t4via86rdia557 and some are putting it together in less than 7 days (some wizards have it down to two days) others several weeks. It is an all inclusive kit (minus TX and RX).
If you are on the west coast, and not able to go to Indiana, there are two meets one is in LA and the other in San Francisco. As Jim said, let us know where you live.
As a side note, you will find that the people on this forum are passionate about the hobby and incredibly helpful.
Peace,
Tom

That is a intriguing kit! Thanks for sharing I am liking the sounds of that one it seems to have the features I am looking for.

[bob the builder]

I have heard good things about Nautilus Drydocks products and service, do you guys think their starter kits such as a Revell Gato in 1:72 would take longer than a couple months to complete the build portion? I was under the impression the entire WTC came assembled and tested, I realize I would have to complete my own tests and trimming/tuning but thats part of the fun and excitement and I dont really include that in the "build" portion of it. I am not trying to ignore or discard your guys advice just trying to get a idea here.

Based on your stated experience, I'd say you'd be able to realistically get the Gato up and running in that time frame (depending on the amount of hours actually worked in that two month period, of course). While older, the starter kit comes with 5hrs of video outlining the build process thanks to Dave Merriman.

If I can help, just let me know.

Bob

[salmon]

Only to add to what Bob said, the Gato and guts that he sells was my first sub I built.





It took longer than a couple of months, but I did more than I needed too and had other life things happen during the build. I love my Gato.

[JWLaRue]

Scott,

Based on the background you provided and your requirements, I'd say it's close to a toss-up between the Gato and the Engel Akula II (or Type 212a). Both can serve you well. Each provides very different type of r/c sub implementation....and each has its own merits.

Since you closed out your post stating that getting a sub up and running is a priority, that would seem to give an edge to one of the Engel boats.

-Jeff

[bob the builder]

Jeff,

I'm curious at the recommendation. In my experience, Engel's suite of electronics is far from simple and the dry hull makes trimming more of a procedure. They make excellent products, but I'd never recommend them for a beginner. Of course, my experience has been with their Nautilus, Typhoon, Gato and Akula kits. I haven't yet seen the new Akula II kits in person yet. Maybe they've figured out a simpler building product...

They're really apples and oranges. Akula is a simple, modern design that would be very easy to finish from a detailing, paint and weathering standpoint. Gato is a WW2-Era fleet boat with tons of details and more operational quirks due to the design. A better comparison would be the Trumpeter SeaWolf or Mobius Skipjack, both of which are very fast, easy builds.

[subdude]

Hi Bob,

I can only speak to one side of this comparison, as I haven't built the Gato. But having recently built the Engel 212a (a slightly more complex version of the Akula II with X-tail and working scopes) I can say that it does have it's merits. Primarily, it's a complete kit, with no fabrication required. Built to the instructions (strong in some areas, weak in others) it goes together quite well. And the new electronics piston tank controller, pitch controller, x-tail mixer, etc are almost "plug and play". If you actually read the instructions ( insert shameful red face here ) it works out of the box. And trimming the dry hull was child's play. Install the supplied weights, and test. I had to reduce the trim weight by perhaps 1/4 oz and shift it from one end side of the battery compartment to the other, but that was it. Trimmed out in a couple minutes. The only complaint I had was the operational periscope system, which isn't on the Akula II anyway.

The entire package is easily build-able by someone with some R/C experience.

The Gato kit I can't speak to, but being a converted plastic model kit, I'm sure that there are some things that need to be done to make it suitable. Most of that has probably been done by the supplier I would imagine. I would agree with you that the Skipjack would be a more apples to apples comparison. There are several conversions that I am aware of which I'm sure all work well. I personally have one on the shelf which is in the build queue. Again, there is the extra detail of converting a plastic display kit to R/C to consider. And starting from zero, the trimming out will take a bit more time.

Either way, I do agree with Jeff that they are both excellent options for someone just getting wet (so to speak) in subs, but with at least a tiny bit of experience.

Jim

[ccontrol]

scottyk,

It appears that you are about a 6 hour drive from this:

2017 4th Annual CARMEL SUB FUN RUN August 5 - 6, 2017
CARMEL, INDIANA

In conjunction with THE SUBCOMMITTEE, INDY ADMIRALS, SubComON, and SubRon8

PLEASE join us for the 4th Annual CARMEL SUB FUN RUN August 5 - 6, 2017.

Located at the beautiful VETERANS MEMORIAL REFLECTING POND,
760 THIRD AVENUE SW - CARMEL, INDIANA

EVENTS INCLUDE:
- DAY AND NIGHT R/C SUB RUNS
- 2 DAY RAFFLE (LOTS OF R/C HOBBY GOODIES!)
- SWAP TABLE
- CAPTAIN CHOICE AWARDS, SUB FUN RUN EVENT T-SHIRTS

MORE INFORMATION TO FOLLOW SOON ON THIS THREAD
CONCERNING HOTEL INFORMATION, SUB CAPTAIN REGISTRATION,
EVENT T-SHIRTS, AND MORE.

Long drive but you would see and learn more in one day than the rest of us newbies get in years of reading about it!

[scottyk]

Thanks everyone for the helpful replies! I do like the looks of the Gato sub more than the Akula, those older sub have more character IMO. and like I said Im not huge on attention to detail and accurate scale features but I also do not want to show off a model of a yellow propane tank I put a gopro on and called it a submarine.

If I could spark a little more debate here I am curious on your guys opinion of the ballast systems used.

The Akula ii uses piston ballast, which if I am not mistaken is a single piston design which I would imagine will affect the attitude of the boat as it is filled or expelling water? I would think it is inevitable that the weight of the water filling the cylinder would change the CG of the boat.

The subdriver module in the Gato uses a pump I believe which would fill and empty the cylinder evenly which makes sense in my head, but I am little confused on the "semi aspirated" design where it states "air to eject ballast water is either pulled from atmosphere through a snorkel within the models removable sail, or from the dry spaces within the SD itself if the model is completely submerged when it is desired to expel ballast water" So to me it begs the question, why not take air from the SD all the time? and how does this system switch between snorkel air and SB air or is that a choice made and built in during the building stage?

And last but not least, operation in general, which sub drives and handle better, has deeper depth capability, you guys like the WTC flooded hull design over the dry hull design?

Thanks again for the opinions guys! and I would love to make that trip to the show, I am however going on a trip to canada starting tomorrow so I wont be able to attend the show but I am looking forward to seeing the videos and pictures at least!

Also, I keep reading about the Akula ii kit being complete, but by my research the Gato comes with everything you need including the radio where the Akula ii kit does not mention including a radio at all. Seems like you would end up with at least a few hundred dollars more invested into the Akula ii in comparison to the Gato kit unless Im missing something.

[Ralph --- SSBN 598]

I will try to answer some of these questions.
-----
Background.
I have built home made submarines of sorts using high pressure Freon. When we could still use it.

I built a hull kit only George Washington.
Ballast is Recirculating air.
A vacuum pump pulls air from inside the cylinder and moves to an external bladder.
A tire valve releases the air fromt he bladder back in to the cylinder using the vacuum created in the cylinder.

I built the Revell Skipjack plastic, model building my own cylinder and internal parts.
This boat uses a water pump to move outside water in to a bladder and then pump it out as well.
Made working masts and after successfully getting them to operate, I removed them as being un necessary.

I in April, assembled an Akula II.
My time to build was 24 hours over 21 days to complete and in the water.
This boat uses a single piston ballast system.
Your concern on the piston ballast system changing the GCG is valid.
I have not had any issues with CG changes as the automatic leveling circuit does a nice job of keeping the boat level when not control input is used.
Something to think about is when running a nuke boat, you usually do not run the boat with the ballast tank partially filled.
You either run on the surface with an empty ballast tank of submerged with a full ballast tank.
Any minor adjustments do not effect trim to where you would notice.
The Akula II is a complete kit with everything to assemble except the radio Tx & Rx.

I keep cost numbers on file.
The cost of the Akula II is a bit of a shock but when I compare it to the other boats I have built, the cost comes very close to being the same after buying all the individual parts.
There is no comparing the time needed.
Akula wins but over a year the way I build.

I to like the looks of the older boats.
I have one I have been building from scratch for some time.
The small details are fragile and can and will be knocked off from time to time, needing replacing or remounting.
-------------------
The system you asked about with the dual air source.
When completely submerged, the pump can not get air from the surface so it pulls a slight vacuum in the cylinder which will cause the boat to rise to the surface enough to get the snorkel above the surface and then the pump draws in outside air which releases the valve that chooses where the air will come from.
It is a float valve that open and closes depending on whether it is above the surface or below the surface.

Why not take air form the cylinder all the time.
It is a matter of needed volume.
The cylinder may or may not have enough volume to completely fill the ballast tank, so additional air is needed.
The old boats are small inside and usually do not have the volume needed for all the air it takes for full surfacing.
You will read about WWII boats that compromise full surface to get full submerged and run at almost decks awash.

The dual system was designed to over come this issue to get full surface and full submerged in a small spaced boat.

There are several ballast systems.
They all do the job they are designed to do.
They all have good point and bad points to deal with.

I find the piston to have more control but it is also the most complicated system to build on your own.
You appear to have all the machines needed so it may not be an issue.
I only have a drill press and hand tools so building a piston would be a challenge for me.
--------
A suggestion that gets put in thread on new to submarines is to consider building a boat that will get you int he water the quickest and teach how all the systems work while yo build the boat of your dreams.
Or have one of the pro builders build for you.

Just a note:
My Skipjack took a little over a year of part time working on it to get in to the water.
I built the plastic hull with all it's control surfaces in 3 weeks of part time building.
The cylinder didn't take all that long but getting it to work correctly has been a different story.
I have made 4 complete rebuilds of the equipment inside.
Each one worked but then came the issues to over come.

So, at this point, I would like you welcome you to the wold of submarines.

[scottyk]

I will try to answer some of these questions.
-----
Background.
I have built home made submarines of sorts using high pressure Freon. When we could still use it.

I built a hull kit only George Washington.
Ballast is Recirculating air.
A vacuum pump pulls air from inside the cylinder and moves to an external bladder.
A tire valve releases the air fromt he bladder back in to the cylinder using the vacuum created in the cylinder.

I built the Revell Skipjack plastic, model building my own cylinder and internal parts.
This boat uses a water pump to move outside water in to a bladder and then pump it out as well.
Made working masts and after successfully getting them to operate, I removed them as being un necessary.

I in April, assembled an Akula II.
My time to build was 24 hours over 21 days to complete and in the water.
This boat uses a single piston ballast system.
Your concern on the piston ballast system changing the GCG is valid.
I have not had any issues with CG changes as the automatic leveling circuit does a nice job of keeping the boat level when not control input is used.
Something to think about is when running a nuke boat, you usually do not run the boat with the ballast tank partially filled.
You either run on the surface with an empty ballast tank of submerged with a full ballast tank.
Any minor adjustments do not effect trim to where you would notice.
The Akula II is a complete kit with everything to assemble except the radio Tx & Rx.

I keep cost numbers on file.
The cost of the Akula II is a bit of a shock but when I compare it to the other boats I have built, the cost comes very close to being the same after buying all the individual parts.
There is no comparing the time needed.
Akula wins but over a year the way I build.

I to like the looks of the older boats.
I have one I have been building from scratch for some time.
The small details are fragile and can and will be knocked off from time to time, needing replacing or remounting.
-------------------
The system you asked about with the dual air source.
When completely submerged, the pump can not get air from the surface so it pulls a slight vacuum in the cylinder which will cause the boat to rise to the surface enough to get the snorkel above the surface and then the pump draws in outside air which releases the valve that chooses where the air will come from.
It is a float valve that open and closes depending on whether it is above the surface or below the surface.

Why not take air form the cylinder all the time.
It is a matter of needed volume.
The cylinder may or may not have enough volume to completely fill the ballast tank, so additional air is needed.
The old boats are small inside and usually do not have the volume needed for all the air it takes for full surfacing.
You will read about WWII boats that compromise full surface to get full submerged and run at almost decks awash.

The dual system was designed to over come this issue to get full surface and full submerged in a small spaced boat.

There are several ballast systems.
They all do the job they are designed to do.
They all have good point and bad points to deal with.

I find the piston to have more control but it is also the most complicated system to build on your own.
You appear to have all the machines needed so it may not be an issue.
I only have a drill press and hand tools so building a piston would be a challenge for me.
--------
A suggestion that gets put in thread on new to submarines is to consider building a boat that will get you int he water the quickest and teach how all the systems work while yo build the boat of your dreams.
Or have one of the pro builders build for you.

Just a note:
My Skipjack took a little over a year of part time working on it to get in to the water.
I built the plastic hull with all it's control surfaces in 3 weeks of part time building.
The cylinder didn't take all that long but getting it to work correctly has been a different story.
I have made 4 complete rebuilds of the equipment inside.
Each one worked but then came the issues to over come.

So, at this point, I would like you welcome you to the wold of submarines.

Thank you Ralph that is the type of info I was looking for, outstanding! The one that surprises me is the comment about the nuke subs running ballast normally full or empty and not much in-between. I had expected the ballast to be a on-going constant adjustment to keep depth steady, but I guess that would only hold true if you are sitting still and not moving forward where I imagine the automatic attitude controller would keep it going level and consistent depth.

and the last comment about 3 weeks of building the hull, but a year to get into the water is not surprising to me and this is what I was trying to avoid on my first sub.. The constant tweaking of home-made parts, and building/rebuilding things that did not work the first time! Although I may be capable of physically building my own piston ballast system and WTC the pains of scratch building is not something I want to tackle head on right now, specially on my first go around. thanks for the real world input it is very much appreciated!