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[TheLongBuild]

Neil
The switch is a break system, so if you are going full ahead you need to put the stick central first and then reverse.  but switching it will then operate straight from forward to reverse or vice versa,.


We use them for the Lowe's Bumper boats on a 7.2v but would probably not use them for anything much higher. They are very sensitive and will blow if connected wrongly !! 

[Neil]

Thank you, Bob, Roy and The Long Build for all your help........got it now, and able to continue hapily, taking on all of your comments as a good learning curve.
In respect of the ampage draw of the motors that were with the boat, and what the gent at Steve Webb models told me about the amps used with these, I will drop the rating of fuse to 10 amp in the online fuse holder as it is a small boat and I dont sail quickly with a lifeboat anyway, and if all goes well with a test in the bath, I'll keep that set up...........
If it goes that I blow the fuses then I'll put in two small Buhlers that I have which draw only 1.5amp at stall anyway and ran a similar model on them a few years ago at a perfect speed with 5 amp fuses in line.
Thank you all so much for your help and patience. My old mate Dave Milbourn would be proud of us all for sorting me out, knowing what he would have been saying by now. lol .

[derekwarner]

Isn't it just like old times ........ ...... ......... .......... .............Derek

[roycv]

Hi all.  Neil, if you are using motors with a 1.5 amp stall current then there is a rule of thunb that efficient operating current  (i.e. under load) is 20% of the stall current.  300mAmps at 6 volts is less than 2 Watts.

Not a lot of power!  Also if the test is done too often it can effect the strength of the magnetic field of the magnet.
I would look for motors that ran at about 2 - 3 amps for most (scale) model boats.  You do not need full power unless you need to stop quickly. 

Also I find a use for 20/24 volt motors but running on 6 cells and you can drive large propellers direct from them.
Roy

[Neil]

Ray, the props are 30mm 3 blade brass, in two tunnels so get quite a bit of boost sat in those tunnels, and with the boat sat on the waterline at 36" loa, and neening no ballastis quite light in weight as well, so should be able to cope well with the two packs of 7.2v ni mhs that i will be using..........but if any mishaps from now on, I'll be back, lol. will start soldering some fuse holders on to wire this afternoon and gert charging my batteries.

Thanks again.

[Neil]

Isn't it just like old times ........ ...... ......... .......... .............Derek

just very much more tolerant and less argumentative and abusive Derek....learned a lot on July 27th 2023 after I regained conciousness, ..........best learning curve I ever had mate. 

[Neil]

just as a matter of interest Ray, I have just done something i have never done before, and that is  I have weighed this model boat and all up including the motoprs and two battery packs, she weighs just 3.238 kilos, SO i think that with the shape of the hull and the props in tunnels I cant think i'll have much trouble with such a set up.........here's hoping.

[Neil]

Now hopefully the last question for you guys on this matter and then i can get on soldering the wires together and shrink wrapping them.

Simple question......... the fuse.........does it go between the motor and the ESC or between the ESC and the battery,

on the red wire of course!
Thank you for all your help.

[John W E]

Hi there Neil


Just to see if you are sorted with your speed controllers yet?  Me, I would fit a fuse between the speed controller and the power supply battery.


I sent from one of those speed controllers from China that HMS Invisible sent for and put a link on about.  https://www.ebay.co.uk/itm/354332472778


 The one I received this morning is either an updated version or the wrong one.  It doesn't have a switch on for isolating the brake and there are no soldering connections on the back for a link to make the speed controller tank steering.  What it does have though is the 3rd wire which you plug into the rudder terminal signal on your receiver and that gives 100% mixing on the two motors when you move the rudder stick.  What I had to do was to connect the single wire from the speed controller via a Y lead; into the receiver and the other leg of the Y lead I connected to a servo to assimilate the rudder servo movement.   This produces the correct procedure for mixing - move the rudder servo and one motor will speed up and the other one will slow down - vice versa etc.


Now, if you disconnect the single wire you just have standard control over 2 motors - forward and reverse and no mixing. 


I will put a few photographs on tomorrow and a few diagrams just in case Neil, you are not happy with the setup you have and you would like to try something this as it is really so simple to set up.


The only thing I would say about the speed controller from China is the gauge of wiring for the said amperage  (30 amps).  More like - I would say - 10-15 amps per channel.


John

[Colin Bishop]

Re fuses:

With a single prop boat then put the fuse between the battery and the ESC.

With a twin prop boat then a fuse between the battery and the ESC is a failsafe, but it is also handy to have a fuse between the ESCs and each motor so that if one becomes jammed or weeded up then the other can still function. In that case the first fuse should be of greater capacity than the individual motor ones. OK, not a big deal but it costs pennies.

Colin

[HMS Invisible]

I agree on the cables. One of my modifications was to replace all cables with 18awg ready-crimped red JST plugs.
The principle modification I thought it would benefit from is desoldering the linear bec to replace with a 3-amp switching type as linear bec power loss (in Watts) = (V_in-5)× bec current

I considered making a post about the product update, but thought I'd wait to show you my modifications at the same time.
The pads for mix/tank steering moved but you will find them if at the edge of the other side if you have not already done so. The battery cable was supposedly beefed up in the update.

I've bought a selection of half a dozen Chinese escs and this was one of only two I thought was worth buying. One to avoid was continuously rated above the fuse rating of the cables.

[Neil]

Re fuses:

With a single prop boat then put the fuse between the battery and the ESC.

With a twin prop boat then a fuse between the battery and the ESC is a failsafe, but it is also handy to have a fuse between the ESCs and each motor so that if one becomes jammed or weeded up then the other can still function. In that case the first fuse should be of greater capacity than the individual motor ones. OK, not a big deal but it costs pennies.

Colin

This is taking a great strain on my brain, guys, but after sending a message to Stavros the other day with exactly the same suggestion that you have made Colin that is what I am doing right now, after going down and getting supplies that I could need from our local car factors.
As for replacing the wiring with heavier grade, HMS, that is one step too far for my feeble mind, I know my limits, and that is beyond my brain AND my arthritic hands and fingers.

[John W E]

This is for reference only, Neil, so don't panic.


As I mentioned earlier on in my last post - I had sent for one of the Chinese twin speed controllers as mentioned by HMS Invisible.


I sent a message to the seller on Ebay, saying that I hadn't received the one in the pictures - strangely enough he asked me for photographs of the one I received, so I have done that.   Some of these are the pics that I sent back.


The last one is to show you the ease of set up with the wires.   The only thing that may confuse people is plugging the single yellow signal wire from the ESC into the white signal side of a Y lead. The male plug side of this Y lead is then plugged into your receiver, leaving the other female side of the Y lead to plug into your rudder servo.


I have done a bit rooting around about obtaining some better information on this particular speed controller; and, it does look as though it has a built in thermal.   So, if it is overloaded on either motor it will shut down until the fault is rectified.


Last but not least, and this is throwing the cat amongst the pigeons Neil; if you look at the old Electronize speed controllers; the ones that used to come with the built in fuse holders -which side of the speed controller was the fuse fitted?   On the battery side.


John

[Colin Bishop]

Last but not least, and this is throwing the cat amongst the pigeons Neil; if you look at the old Electronize speed controllers; the ones that used to come with the built in fuse holders -which side of the speed controller was the fuse fitted?   On the battery side.

Interesting point John, do you protect an ESC where the juice goes in or where it comes out, or does it depend on the internal circuitry?

Colin

[HMS Invisible]

Neil, I had John W.E. in a quote box but  subsequently deleted it along with photos. Then Colin posted before me. It would have been clear the cable comment was for John before I took the axe to the reply.

John, the original spec on the Ebay sale photos lacked motor connectors too.
I'm showing the white loop I added to switch to "independent" throttles. It connects the processor pin #1 to O volt. I scratched off conformal insulation on the 0-volt ground plane as the tiny pads only suit a solder shorting link.

  Note that all that prevents the 5-volt red wire from shorting to O-volt is conformation green conformal coating and solder wicking up the cable to make it rigid. It needs attention, but that's what you expect from Ebay escs.

 I've drawn a yellow box round the thermistor. In my opinion this arrangement doesn't give full protection.

[Neil]

This has become a very interesting topic for me, and must admit I am learning a little more about these things, although there are still words and frases that I still dont understand............but do get the guist of what you are all saying.

Talk about a steep learning curve....I Think I am walking up the steapest...........but learning a little more each day.

thank you all.

[Neil]

Thanks all for the info and encouagement to attempt the installation and wiring for my two motors in to the lifeboat, as I have minimal space to fit it all in.

I have spent more time thinking of and constructing this wiring harness than any other in my long career of radio controlling models but finally after a few brain farts this afternoon which I wont go in to due to my own stupidity I have succeded in making the harness, soldering where needed and using connecters when near to the units where heat might have damaged them and it is now ready to fit in to the boat and the little cubby holes where things can fit.

The batteries are charged for propulsion and I have plenty of fuses..........just have to pick which of my 40 mhz tx/rx sets to use as I havent used a single radio in over 3 years sinse my completion of my last Liverpool boat in the photo below.

Wish me luck.

[minimariner]

               
                          PM sent,       Bryan.

[Neil]

               
                          PM sent,       Bryan.

reply sent Brian.

[John W E]

hi there Colin


I haven't disregarded your question about inline fuses - I just didn't want to turn this topic into a subject or a debate which would put a lot of average modellers off electronics.


As in the case of the Sunday morning pondside discussion - where someone has asked the question about electronic components and he being a newby to the hobby - and, shall we say, all the electronically minded members of the modelling society jumping in with 'over the top answers' which the newby may find uninteresting/daunting/put off the hobby.


here is a link from Mtroniks' website about fuses

https://www.mtroniks.net/download.asp?ResourceID=1984

Electronize originally fitted the fuse on some of their speed controllers. because they were receiving a lot of returns stating that it did not work - and the user of the speed controller had not connected the battery to the speed controller the wrong way .   But, when opening up the speed controller; it was easy to tell that it had been connected up the wrong way.     Either burnt out the output transistor or the track had melted on the printed circuit board.


Here is one for you though - on The Crusader model I built - the speed controller handles up to 200 amp at 50 volt.  Also the ducted fan on the Crusader model can ask for that amperage when starting up.  So, that would melt any inline fuses - so she doesn't have any - she has what are known as anti spark connectors.  There is no on/off switch between batteries and speed controller also, so, the plug is the switch that is plugged into the battery.


John

[MikeMcP]

oops
looks like that link is a little bit broken 

[John W E]

woops testing you all out - here - see if this one works for you all 




https://www.mtroniks.net/download.asp?ResourceID=1984

[Neil]

Leads 1 and 2 are battery and motor connections. There lies the conundrum. Can those wires really handle the current required for the motor(s). I certainly don't think so Neil.


Bob

re; this photo. Bob,
I have wired up and soldered all joints, testing each as i did it with a motor at one end and a battery at the other, and so know all joints are tight and sound.

So when i finished and put them all together put power from a battery to the RX and conected up the other plugs to the rx..............ABSOLUTELY NOTHING except for the red power lights coming on inside the esc's.
Tried the circuits with two different charged tx/rx 40mhz systems and nothing.
so could it be from the diagram that lead 1 could be to motor and lead 2 to the battery, as both radio sets had different frequency chips in them

[John W E]

Hi ya there Neil


As far as I can see, you have done it right - I have just double checked your layout with the same speed controller - cos I have one too.


The only thing I am unclear of is, have you used a separate battery to power your RX? and another battery to power your motor - in other words - using 2 batteries?    If so, this is wrong.  The speed controller has a built in BEC which dispenses with the requirement of a feed for your RX from a separate battery.


The other thing is - it doesn't matter if your transmitter is 2.4 or 40 megs - the speed controller will not know the difference - as long as your receiver matches your transmitter.


When you switch on, you should get a few little beeps from the speed controller to signify that it is receiving and you may have to set the throttle range by moving your throttle stick from the centre position to the bottom and back up to the centre.


Couple of pics here to help.


John

[Neil]

i started off without a seperate battery to the esc and got nothing, so plugged in a batery pack yo each of the esc's and still got nothing........so if the former should work on the pins that you and Bob said was right and i have looked closely at yours compaired with mine and have done that right, then it must be a problel with both my old rx/tx's.

I'll try another 40mhz and a 2.4 system that i have. cheers.