Revell US Navy Submarine GATO Class

[Steve2381]

Hello

New man on the block.

I have been given a 1/72 Revell Gato class submarine - not yet assembled.

I am hopefully going to convert it to a static dive model.

I am pretty nifty when it comes to construction and electronics so I don't think there will any problems on that side of it, but I thought I would start a thread and ask for any tips.

I was planning to have a tank at either end of the sub, and an air tank in the middle. This tank would be pressurised when above water using a small 12v car compressor I have spare. Then I can use this pressurised air to 'blow' the tanks when I need to.

My questions...

The auto depth modules you purchase.... do they keep your depth constant using servo operated planes or by adjusting your ballast?

What is the best way to waterproof the servos (or shall I just buy waterproof servos to start)

What is the best way to waterproof the driveshafts for the prop motors.

Thanks all in advance, and I will keep a photographic record of progress

Steve

 

[subzero]

HelloNew man on the block.

I have been given a 1/72 Revell Gato class submarine - not yet assembled.

I am hopefully going to convert it to a static dive model.

I am pretty nifty when it comes to construction and electronics so I don't think there will any problems on that side of it, but I thought I would start a thread and ask for any tips.

I was planning to have a tank at either end of the sub, and an air tank in the middle. This tank would be pressurised when above water using a small 12v car compressor I have spare. Then I can use this pressurised air to 'blow' the tanks when I need to.

My questions...

The auto depth modules you purchase.... do they keep your depth constant using servo operated planes or by adjusting your ballast?

What is the best way to waterproof the servos (or shall I just buy waterproof servos to start)

What is the best way to waterproof the driveshafts for the prop motors.

Thanks all in advance, and I will keep a photographic record of progress

Steve

Hi Steve and welcome.

You can buy an automatic levelling device that will keep the boat at a constant depth by manipulating the rear ( usually ) vanes, a static depth control + leveller is available and works off water pressure and mechanical movement of the vanes but will be too large for the gato.

You should fit the servos in the pressure module you build then there is no need to waterproof them.

Also the 12v car compressor is probably too large for the gato as it just about fits into a 4 " pipe ( just ) unless you have found a tiny one that i don't know about, + 12v is a lot of battery in such a small space, you will end up with 12v and no amps. 6 or 7.2 v is a better option.

You can purchase a small air pump from a blood pressure monitor that will give enough pressure and work on 6 v and is only about 2 " long by 1 " wide. ( about a tenner )

You get neutral boyancy with the tanks then " fly " under the water with the vanes..

You can just grease the shafts with a good waterproof grease which will keep the water out at least at the depths you will be sailing at or to be more of an engineer about it fit a simmering on each shaft ( small O ring ) they are available.

Finally construct 1 module with 3 compartments with the centre as a ballast tank, fore and aft as the pressure hull + for the electronics.

Hope you find this of use.

Regards Sub.

 

[Steve2381]

Wow, many thanks for all that advice.

I was under the impression it would be better to have a tank forward and one aft, but one tank sounds much easier. Also, I know space is tight in the model.

The 12v compressor I have is pretty neat, but the 12v supply weight and size was always going to be the issue - thanks for the tip regards the blood pump.

Any suggestions as the best thing to use as a waterproof module? I was just thinking of using standard good quality water pipe with screw fittings.

I would like clear acrylic ideally, but I don't have the facilities to make that.

Has anyone on here already converted the Gato? Never thought to look!

Many thanks for your time

Steve

 

[subzero]

Wow, many thanks for all that advice.I was under the impression it would be better to have a tank forward and one aft, but one tank sounds much easier. Also, I know space is tight in the model.

The 12v compressor I have is pretty neat, but the 12v supply weight and size was always going to be the issue - thanks for the tip regards the blood pump.

Any suggestions as the best thing to use as a waterproof module? I was just thinking of using standard good quality water pipe with screw fittings.

I would like clear acrylic ideally, but I don't have the facilities to make that.

Has anyone on here already converted the Gato? Never thought to look!

Many thanks for your time

Steve

Steve,

You are welcome.

If you go for Acrylic Tube then go for cast rather than extruded cast is much more expensive but doesn't have the stresses inherant during manufacture that extruded has. But it all depends on price / availability etc.

Check out the web if you want clear acrylic tube, if not then you can use approx 2 " dia plastic pipe.

You will need 4 bulkheads, you can make then from 2 parts if you don't have access to a lathe, one section will be the internal dia of the tube and the other the external dia of the tube and bolt / glue them together with an o ring for the seal between the caps and the tube with longtitudinal threaded rods passing through the entire module holding it together with o rings between the compartments. Then air you pump out of the central part of the module you can store in the front section and use a schreader valve to allow it back ( a car tyre valve with the rubber removed ) depressed by a servo.

Just for your info you will need a ballast tank that can accomodate enough water that equals the weight of the above water line weight of the sub. ( For info 1 KG of weight is equal to 1 ltr of fresh water. ) Make the tank a little larger than the above water line weight. ( this will allow for water temperature differation ) as the temp will affect the bouyancy.

Also a brass tube needs to be inserted between the fore and aft compartments ( to allow the cables for servos etc to pass throught the ballast tank ) seal the tube after the cables are passed through ( keeps the air in one comp when removing it from the ballast tank upon diving.)

There are builds of this type of system on other web sites, the sub committee site comes to mind check it out.

Hope this is of use.

Ps I have included a pic of a module I built for my 1/96 HMS Vanguard in 1998 for you info, should give you an idea what I am on about.

PPS

If you get hold of a Model Boats magazine for April 1998 you will find a front page with the Vanguard on + a 6 page build report that I wrote for the Vanguard with pics of the build / module etc that should explain all.

Regards Sub.

View attachment 19941

 

[Steve2381]

Many thanks Sub. I am looking forward to this build!

Steve

Steve, You are welcome.

If you go for Acrylic Tube then go for cast rather than extruded cast is much more expensive but doesn't have the stresses inherant during manufacture that extruded has. But it all depends on price / availability etc.

Check out the web if you want clear acrylic tube, if not then you can use approx 2 " dia plastic pipe.

You will need 4 bulkheads, you can make then from 2 parts if you don't have access to a lathe, one section will be the internal dia of the tube and the other the external dia of the tube and bolt / glue them together with an o ring for the seal between the caps and the tube with longtitudinal threaded rods passing through the entire module holding it together with o rings between the compartments. Then air you pump out of the central part of the module you can store in the front section and use a schreader valve to allow it back ( a car tyre valve with the rubber removed ) depressed by a servo.

Just for your info you will need a ballast tank that can accomodate enough water that equals the weight of the above water line weight of the sub. ( For info 1 KG of weight is equal to 1 ltr of fresh water. ) Make the tank a little larger than the above water line weight. ( this will allow for water temperature differation ) as the temp will affect the bouyancy.

Also a brass tube needs to be inserted between the fore and aft compartments ( to allow the cables for servos etc to pass throught the ballast tank ) seal the tube after the cables are passed through ( keeps the air in one comp when removing it from the ballast tank upon diving.)

There are builds of this type of system on other web sites, the sub committee site comes to mind check it out.

Hope this is of use.

Ps I have included a pic of a module I built for my 1/96 HMS Vanguard in 1998 for you info, should give you an idea what I am on about.

PPS

If you get hold of a Model Boats magazine for April 1998 you will find a front page with the Vanguard on + a 6 page build report that I wrote for the Vanguard with pics of the build / module etc that should explain all.

Regards Sub.

 

[Steve2381]

Hi all

Ok. I have a daunting box of Revell parts and several evenings reading on the internet under my belt... lets start this build.

I have a few questions that I have no been able to 'google' an answer for:

What is my best option for actual access into this particular model? Through a removable top panel or through a removable nose section.

I am guessing a top panel will make connecting servo linkages to the dive planes easier.

Are the supplied front dive planes going to be good enough to give this model the required control? It is a static dive system, but the planes still need to do their thing.

I am using the air pump out of a blood pressure cuff as suggested by Sub. I assume its the type that inflate a cuff around your arm!

How the hell do you work out your displacement above the waterline before finishing the build! Is there some kind of 'rule of thumb' for the size of the ballast tank?

Finally, how do you pair a motor and prop? I am assuming you get a better prop online somewhere.

Oh, and my radio gear is 2.4Ghz - I assume that will still be ok for underwater use.

Sorry about the questions but I am trying to suss this out as much as I can without battering the forum with questions.

I will keep a full build record with pics and post them for anyone else who want to go the same route.

Thanks again

Steve

 

[subzero]

Hi allOk. I have a daunting box of Revell parts and several evenings reading on the internet under my belt... lets start this build.

I have a few questions that I have no been able to 'google' an answer for:

What is my best option for actual access into this particular model? Through a removable top panel or through a removable nose section.

I am guessing a top panel will make connecting servo linkages to the dive planes easier.

Are the supplied front dive planes going to be good enough to give this model the required control? It is a static dive system, but the planes still need to do their thing.

I am using the air pump out of a blood pressure cuff as suggested by Sub. I assume its the type that inflate a cuff around your arm!

How the hell do you work out your displacement above the waterline before finishing the build! Is there some kind of 'rule of thumb' for the size of the ballast tank?

Finally, how do you pair a motor and prop? I am assuming you get a better prop online somewhere.

Oh, and my radio gear is 2.4Ghz - I assume that will still be ok for underwater use.

Sorry about the questions but I am trying to suss this out as much as I can without battering the forum with questions.

I will keep a full build record with pics and post them for anyone else who want to go the same route.

Thanks again

Steve

Steve.

Unfortunately the 2.4 ghz will not work underwater the signal won't penatrate the water sorry, you will need a 40 meg set about 4 channel for the minimal but 6 is better.

You can split the hull down the waterline ie half way up lifts off or just the decks or whatever way floats your boat. If you weigh the above water parts, ie deck tower and hull bits it will give you the weight then convert to ltrs, ( 1kg = 1 Ltr )

You will prob only need something like a pair of 400 size motors for the sub and if you can afford it buy some scale "Prop shop" brass props, better performance, scale effect etc.

The kit hydroplanes will be ok size wise.

Hope it all makes sense and is of use.

Regards Sub.