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[clockworks]

I've just bought another boat, as the first one I bought has a nasty leak. Fixable, but it'll take a couple of weeks to dry out first. That was my first ever boat, so not a good start!


One thing I found at the lake, using my car wheel radio, was that it's a pain when launching and retrieving the boat. Hanging a stick radio on a strap seems much more sensible. I never got on with sticks for cars, but didn't have a problem with sticks for planes (no choice really).


Anyway, since model boats are new to me, I think I should give sticks a go right from the beginning. The wheel radio is basically a KO 3 channel chassis with Spektrum DX6i electronics. It worked fine for cars and a rock crawler, but the controls are a bit non-linear due to using the KO pots with Spektrum circuitry. It's a bit of a faff setting it up for boat use.


I have a Futaba T7C transmitter, and quite a few receivers in my old planes. I'm not going to fly again, so I want to use this radio for boats.


Presumably the basic stick arrangement is the same as for 2ch sets - throttle on the left, rudder on the right?
I've got a broken 35MHz Futaba that is mechanically the same, so I should be able to use bits from that to convert the throttle to self-centering. Is that all I need to do? Leave it set for "mode 1" and remove the ratchet, then calibrate the ESCs to the radio?


What do model-boaters that use multichannel radios use the other channels for?  The "new" boat that I'm just setting up has twin motors and ESCs. Which channel is conventionally used for the second motor (via a mix)?
Another boat that I also picked up yesterday has working fire monitors, lights, and a sound module. Any conventions on which channels/controls to use for these?


I know that I could just do my own thing, but it makes sense to set things up the same as everyone else. Makes using other people's kit easier, for instance if I want to try a sailing boat.

[JimG]

If you are using mode 1 then the throttle without a spring is on the right, The left stick has a centering spring so wouldn't need altered.Usual controls are throttle on left stick (forward to go forwards and back to reverse) and rudder on the right. In mode 1 these would be channel 1 and 2 on the receiver. Throttle mixes tend to use channels 5 and above as these are switched or a rotary switch however unless you want to use motors for steering a y-lead is just as good. Again lights etc are usually on a switched channel so channel 5 and above.What you need to watch for is if both escs have a BEC to power the receiver then remove the red lead from one of the plugs so only one is providing power. You can cut the red wire but it is better to remove the terminal from the plug and tape it back against the wires. This woulod allow you to reconnect it if the esc is used on its own.
Jim

[john44]

Hi, you stated you are thinking of using your old plane recievers and transmitter on 35 MHz
You can use 27 or 40 MHz and 2.4 not 35 MHz for boats.
Follow jimG post for stick channels


John

[clockworks]

Thanks for the info.  Must be mode 2 then, as my plane setup is throttle on left stick. I mistakenly thought that was mode 1. Good point about using ch5 and above for the mix, as moving the left stick left/ right or the right stick up/down would make the motor on mix Ch 3 or 4 run.


One of my Futaba receivers is only 4 channels, so that one with a y lead might be easier. I'll keep the 7 Ch receivers for the more complex boats.
I've pulled the red wire pin from one esc extension lead already.


The radio I'm going to use is 2.4. It's my broken one that's 35MHz - battery pack leaked over the PCB.


Would channels 3 and 4 ever get used for boats?


Just a thought:


If I used a mix with ch5 for the second motor, could additional mixes be set up to add a bit of right motor with left rudder input, and left motor with right rudder input to give a bit of motor assistance for steering? Can mixes be used that way?

[JimG]

Would channels 3 and 4 ever get used for boats?

Just a thought:

If I used a mix with ch5 for the second motor, could additional mixes be set up to add a bit of right motor with left rudder input, and left motor with right rudder input to give a bit of motor assistance for steering? Can mixes be used that way?

It is quite common to use a mix between rudder and separate escs to give improved steering. You can arrange the mix to give full opposite motors with full rudder and zero throttle allowing the boat to spin in its own length. I have done this in the past although using an external mixer not the transmitter as older sets did not have mixing.
As for the other channels if you do have a mode 2 set then you will be using channel 1 for steering and channel 3 for throttle. Some use channel 2 and channel 3 for independant throttle controls without mixing (Left and right sticks forward and backwards). This gives what is called tank steering allowing you to use the throttles to steer but takes much more practice to sail in a straight line. Channel 4 (left stick side to side) is less often used although I have seen it used to give steering to throttle mix while leaving the right stick purely for rudder. Again a much more flexible use but needing a lot of practice to remember which stick does which. To show how complicated things can get I have the Graupner Parat tug with two Voith Schneider drives, one controlled by the left stick using 2 functions and one by the right again using both directions of movement. Steering and direction is controlled from both sticks at the same time as they interact with each other to control direction, took quite a bit of practice to steer a consistant straight line (or move sideways).
Jim

[clockworks]

Thanks. I've been confusing myself about channels and modes, as that's how I built my hybrid wheel transmitter.
I've dug out the Futaba manual now, and it does indeed confirm that I was wrong. My T7C is mode 2, throttle on the left stick ch3.


Looking at all my old planes, I've got 3 genuine Futaba Rxs (one of which is a 4 channel), and 2 Chinese compatible 7ch.


I'll try and set the Riva up with the ESCs on separate channels, and try a mix with the rudders for faster steering. Looking at the size of the rudders, it probably won't need much at high speed, but it might come in handy when moving slowly. Since I'm new to boats, it never occurred to me that a single prop boat can't steer very well when it's moving really slowly. Not a problem with planes, as they fall out of the sky if they go slowly.
If I can't get my head around it, I'll use a Y lead.