torpedo system

[Subculture]

You have something like this-

http://www.maxwell.com/pdf/uc/datasheets/PC_series_1003996_rev8.pdf

However, they would only suit larger scale torpedos.

There are some truly tiny Li-pos available nowadays with impressive amounts of charge, and I would look at those. I reckon you could get down to 1/72nd scale with an electric torpedo, 1/96 scale would be difficult.

You could switch them on and off using reed switches and an electro magnet via a small microcontroller feeding a MOSFET to the little motor. the same microcontroller can be programmed to feed the motor for a specified time (say 5 seconds).

This stuff is so small it could all be mounted inside the torpedo. The electromagnet would be mounted inside the submarine and switched via a spare channel.

[Slats]

I think you'll find the little helicopters use small single cell li-po's- the ones I have do.

You can use an ultra capacitor for power, these are more widespread now, and under constant development- they're looking to fit them to electric cars.

Andy,
thanks for this.......any ideas for what cap would be useful for a scale warshot or around say 1/72?

I'm still going gas with David - but I'd still like to know.

J

[Subculture]

I think you'll find the little helicopters use small single cell li-po's- the ones I have do.

You can use an ultra capacitor for power, these are more widespread now, and under constant development- they're looking to fit them to electric cars.

[Slats]

Have just seen in the mall here an application that might be worth studying Rick
Those tiny IR helicopters run on these caps.

The IR TX doubles as a charge station for the helicopter
The helicpoters feature tiny motors (similar to what you have posted)
The helicopters have counter rotating blades....

So there is the ingredients of what I would study to take the electric warshot further.

Now David how about those pain in the butt questions mate?

J

[He Who Shall Not Be Named]

I know that I better give credit where credit is due: Dan Kachur, out of Canada, one of the best builders and operators in this game today. He's done effects work for the Canadian film industry (X-files is one credit he has).

He perfected the electrolytic torpedo years ago and they have all the attributes you observed, John.

He sent me a video of his torpedoes -- fantastic work!

David,

[Slats]

Substitute the battery with an electrolytic capacitor and you're home free.

David,

God he's good. :)
By doing so - you can not worry about a kill switch as the full discharge can be dumped into the motor - so the torp just stops when its out of fuel. Just need to figure out which electrolytic cap would suit the motor and desired torque for best effect.

The weight issue - gone too.

You just need to:
-counter the torque roll
-build a release mechanism (you could use a reed switch thats NO and trigger switch / circuit closure and motor start via rare earth magnet on a push rod that comes along side the torpedo near the reed switch).
-work on a charging mechanism

David is there nothing you don't know.:D


J

[He Who Shall Not Be Named]

I really appreciate the suggestions, But I've seen battery powered, single-prop, torpedos that work and operate the way I want mine to. So I know it can be done.
Now wheather I'll be able to construct them with one good hand is another concern but i want to try for several reasons. The biggest ones being that I like to create my own designs and fabricate them and the other being that I know I'll not be able to afford David's creation, since he's going to be very proud of it, and rightfully so. :D LOL
Thanks,

Substitute the battery with an electrolytic capacitor and you're home free.

David,

[Slats]

well I am sure David will confirm it, but his system I think should fit the Revell Gato.

J

[toppack]

The Revell Gato is the one I've completed.
I also have Revell U-boat and the fiberglass T-class in the works.
Most of my RC ship model building experience is with surface ships, 17 operational, and I'm really enjoying learning about subs. :)

[Slats]

Rick what subs are you running?
J

[toppack]

Yes, We will see.
I'll try fo find those videos of working torpedos again.

[Slats]

I really appreciate the suggestions, But I've seen battery powered, single-prop, torpedos that work and operate the way I want mine to. So I know it can be done.
Now wheather I'll be able to construct them with one good hand is another concern but i want to try for several reasons. The biggest ones being that I like to create my own designs and fabricate them and the other being that I know I'll not be able to afford David's creation, since he's going to be very proud of it, and rightfully so. :D LOL
Thanks,

Rick - have you got a link to the torpedoes you mention?

Next - I only call it a deadhorse as I have been in this game a long long time.
In fact the Australian Subregatta (every 2 years) is a torpedo fest - all are gas and for the reasons I have spelled out. That regatta brings several hundred years experience to it.

I am not knocking innovation or discovery - you do what you want - but a lot have tried what you have and are attempting, some following the route you are documenting and have got it wrong more for the reasons of physics than lack of effort or resources.

Remember here, the problem is not just simply building the torpedo, it’s the release system, the integration with the boat etc etc.

I'll be happy to give you congratulations for your efforts and success. It takes guts to keep going especially with just the one hand. Indeed well done that you are in this hobby!

As far as affordability goes mate – lets see what the price is first. Indeed how do you know you can’t afford it unless you know the prices, which I understand have not been released? All too often in this RC sub game, I see people (particularly the new guy) thinking that they will build their own boat and WTC to save money. For most, in the end, the duplication of costly errors of inexperience add much more cost than buying off the shelf. Been there done that too.

Best

John:)

[toppack]

I really appreciate the suggestions, But I've seen battery powered, single-prop, torpedos that work and operate the way I want mine to. So I know it can be done.
Now wheather I'll be able to construct them with one good hand is another concern but i want to try for several reasons. The biggest ones being that I like to create my own designs and fabricate them and the other being that I know I'll not be able to afford David's creation, since he's going to be very proud of it, and rightfully so. :D LOL
Thanks,

[Slats]

Forgot to mention another reason why I like Gas...

wake trail left by bubbles very realistic.I'll drink to THAT!

J

[Slats]

Rick been there done that,
and it flopped. Thumbs Down

My electric torpedoes had one big problem - flotation
You will find you need as Andy put it - around 3 volts for enough torque transfer to the prop in the water. This is where the weight problem creeps in, along with torque roll which in my scale was too little to have counter-rotating props (which I countered to some degree with weight distribution and fin set up.

Back in the 90s there was a couple of great large scale (1/24 and 1/32 i think) electric torpedo kits you could buy - no more of these around - these were works of great craftsmanship, counterrotating props etc etc, the real deal.

Why do I like gas-
Its simple.
There is no flotation problem
There is no battery requirements
There is no bearing
There is nothing on each shot to water proof
There is no kill switch requried
There is likely (awaiting confirmation from David) no or very little ballast impact on the boat.

The latter problem is potentionally huge with a battery (weighty torpedo).
Don't believe me do this test:

Take a sub that you operate regularly. Take her down in to PD. (Tank should be full of water.

Take one AAA battery plant it via rubber band on the nose - what happens to your trimmed out boat? Its now a little nose heavy - ok multiply that by say a factor of say 8 to represent 4 medium to small type 3 v powered electric torpedoes - you now have a boat that when "armed" is in a completely different ballasted state to when not loaded with torpedoes.
To over come this you need some way of equalising the weight of the loaded tubes when the tubes are unloaded. Its not impossible but the only way I did this was by making the torpedo overscale in length and made each torpedo positive. I had a separate tank on board to pump in /out water to counteract the release of each torpedo.

In short the system was complicated and craptacular; and was uninstalled from my Permit PDQ.

Rick, stop flogging this dead horse mate - IMO you are wasting your time and resources.

Just wait for the system - David will answer my question list (he is kind of busy):) and you will be blown away as to just how good the system is.

Best
J