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[Mach1]

I am installing two electric motors in my 49inch Dumass Dauntless and wish to control them separately, so that in the event of a motor, esc, fuse failure I will be able to recover the model using the other system.
I am unsure how to rig a transmitter that will give me both sticks spring loaded to the central position.
I have a Planet T5 and a Planet T7 transmitters and was wondering if I could take the spring loaded stick from one of them and install it in the other.
Is this at all possible.

[Martin (Admin)]

How will the motors be installed, left and right?

[Alanmclellan]

Yes, one motor on each side

[Colin Bishop]

You can still protect each motor individually by inserting a fuse between it and its speed controller. If one prop becomes fouled the other will still work normally.

'Tank steering' can often be awkward to use on a model boat and many people prefer to use a single stick/mixer arrangement which helps give a smoother response.

Colin

[Mach1]

Thanks for the advice Colin. I did try “tank steering” on a model tug and as you say it was not good at all. I will definitely go for a mixing unit for a smoother operation especially as this will be a fast boat.

[kinmel]

All my twin prop boats have separate port and starboard power trains etc.

Bind 2 receivers to the transmitter, I have not yet owned a R/C set that could not bind 2 receivers.

 The power circuit on each side is battery> fuse> switch> Rx with the channels replicated on both sides.

[Akira]

As Colin said, simply fuse each motor between the motor and the speed control. Even if only one ESC is used to control both motors, there will be a get home motor, unless both props are completely fouled.(stay out of the weeds). This applies if each motor run off it's own battery or if they share a battery.
I have to disagree with the opinion of using two receivers. While, yes, it can be done and in some cases makes a lot of sense, (two water tight cylinders in a sub), in this case it is an extreme violation of the KISS principal.Even if you you chose to use two separate speed controls, the motors should be fused, or even better auto reset fuses or circuit breakers, to protect the motor, wiring and hopefully the ESC for excessive loads in the even of a prop fouling.
 

[kinmel]

It is not an "extreme" violation of KISS, it is using the simple, well understood, single prop setup, twice.

 Independent power trains also eliminates the "one is none" principle at minimal cost.

[Mach1]

Thank you all for your helpful advice. On my bench I have two motors, two speed controllers, awaiting a mixer unit (today) and a receiver.
I will put it all together as suggested and see how it goes.

[Akira]

Kinmel, I apologize if I sounded rude. I did not mean to. Your system is perfectly valid, it is just that in 50 years of running R/C, your suggestion is the first time I have ever heard that idea, for running a surface boat. Personally, I accept the idea that if I were to suffer a radio failure on board the model, that I will be paddling for my boat, or sending out the rescue tug.cheers

[kinmel]

Akira, not a problem. Here in north Wales we sometimes sail on very deep, very large lakes. In the disused quarries you can have 5 metres of water just 5 metres out, so independent power trains are a worthwhile feature.

Everyone to their own. I put the fuses at the battery because that is where the 200amp overload originates if there is a short circuit, or a stalled motor. 

[Akira]

Kinmel,Agreed, that is where I put mine. Smooth sailing....

[RST]

Folks have we missed the objective of the OP here?


I always read it as a few questions mixed in:


Redundancy:  On a twin screw model you can take advantage of that firstly by dual fuses from single esc to each motor then by dual esc's off a y lead.  You can go further by dualing up more, how far you take it it is personal choice I guess

Having independent motor controls:. Well if it's for the operability then you either go for tank steering or an electronic mixer or a mixer in the tx.  Old days of using microswitches to reverse an onboard motor polarity are still valid but not used much now I guess

How to convert LHS vertical stick to centre return:. I can't comment much on that, when I bought my tx, a spring conversion kit was a pre-requisite for me, some might say I just limited my choice of radio gear


...reading the OP question having a second stick as a return to shore function doesn't really fit so easily on an electric powered model.


I think this worked out a bit of a complicated set of answers to a relatively straightforward concern.


There's also the rarely referenced guides on model boats forum that never really get talked about so what's the point in the authors writing them?  I'd post a link but am on my phone and cans find them, but they're there in the technical articles section and a good read, the principles have applied for donkeys surely.


Rich

[malcolmfrary]

Most ESCs have some sort of protection and a fuse between ESC and motor is not only redundant, but also a positive fault liability, only useful as a connection point for a meter.  If running more than one motor from one ESC, a fuse to each motor becomes useful and sensible.
A fuse between battery and ESC protects the boat against faults in the ESC and anything else beyond.
If that is a genuine worry, it is no good relying on a built-n BEC.  If the fuse supplying the ESC with the active BEC blows, the radio also stops working.  A separate radio battery comes into its own in this case.  Or a discrete BEC directly connected to a main battery.

[Mach1]

One again thank you for all your suggestions to my original query. Should I use one ESC for both motors or have two ESC’s, one for each motor.

[Mach1]

One again thank you for all your suggestions to my original query. Should I use one ESC for both motors or have two ESC’s, one for each motor.

[justboatonic]

One again thank you for all your suggestions to my original query. Should I use one ESC for both motors or have two ESC’s, one for each motor.

Unbelievable some of the answers on here. If you have a multi motor scale model or a fast, multi motor model, you really need two (or more) escs and a mixer or multi motor esc with built in mixer. Yes, this is more expensive but if you run twin motors off one esc on a fast electric model, your turns will be wide and horrendous. This is because both motors will be running at the same speed parallel to the centre line of the model while the rudder(s) try and make it turn. You ideally want the inside prop in a turn to slow down so the model turns quicker, more smoothly and more controllably.

[Mach1]

Thank you for the explanation and it now makes complete sense to me. As I already have two ESC’s I will install them and see how I get on.