Brushless motors

[BRYAN ASTONParticipant @bryanaston57723]

Dave

I could not figure out how to connect two 7.2 v battery packs in series ,so I bought a 12v 10 cell battery pack , had to modify the Sea Commander bulwarks to fit it. I have not run the boat with 12v yet as the charger I had does not charge 10 cells, ,delivery expected 2 nd of June. The boat running on two 7.2v , battery packs in series and a 700. Series motor goes like the clappers, do I need brushless motor ? I will probably try one in the Huntsman in due course. Thank you for your help.

Bryan

[Dave MilbournParticipant @davemilbourn48782]

Series wiring is connecting a positive wire of one battery to a negative one of the other, and using the "spare" positive and negative wires as the connections to the load. This will give you a total voltage across the batteries of the two individual voltages added together. It's all in my article here **LINK**

Whether or not you need a brushless motor depends largely on you. It might be forced on you if the motor brushes or bearings burn out (but I doubt this would happen) or if you decide you want a longer running time. Brushless motors are far more efficient than brushed ones so will run for longer, given the same power output and battery capacity.

I only know of one brushed motor which would power a big Huntsman – and they are not available any more (at least not new).

Dave M

[BRYAN ASTONParticipant @bryanaston57723]

Dave

I obtained suitable cables and connectors and joined two 7.2 battery packs in series in the Sea Commander and I was amazed how fast the boat went, only a very few inches of the hull was touching the water and quite a few other boaters asked what motor I was using ,most assumed it was a brushless . The only downside was the heat the motor generated, perhaps I should water cool it. I did know how to connect two batteries in series, I was a signaller in the army, Thank you for all your help.

Regards Bryan

[Dave MilbournParticipant @davemilbourn48782]

Bryan

All you need to ask yourself now is whether or not a 50's Broads cabin cruiser looks right with 90% of its hull out of the water!

Water-cooling will help – clearly. You might also find that a different prop (e.g. a finer pitch) will tame the model a little but reduce the motor's temperature a lot – and increase the running time. You don't need to buy Prop Shop's little artworks at twenty quid+ a pop.

Ref 'series wiring'; I'm sorry if you found what I said patronising – it was in response to what you said about not being able to figure out how to connect two 7.2v battery packs in series. Believe it or not there are people out there who wouldn't have the vaguest idea what we're talking about.

Dave M

[BRYAN ASTONParticipant @bryanaston57723]

Dave

I agree that a broads cruiser would not go at that speed in real life ,but it did look quite spectacular , I was using the Sea Commander as a test bed as it has a very strong hull.

I will now fit out the the large Huntsman with the same system to see if I get a similar result because that should have most of its hull out of the water.

Ref. my previous communication about the brushless motor I bought from China that I could not get to work, I have now received a replacement by airmail no problem. I think a lot of the problem was pilot error.

Regards Bryan

[Dave MilbournParticipant @davemilbourn48782]

Bryan

This is what a Huntsman should look like with all the stops pulled out **LINK** This one is only 1/16 scale. Now imagine that at twice the size………

Your comment about pilot error was both honest and revealing. I've said before that at least half of the units we ever had back "for repair" were perfectly OK. If only everyone read the instructions before they connected the thing up and switched it on – or at least admitted afterwards that they hadn't! I could tell you some tales.

Dave M

[BRYAN ASTONParticipant @bryanaston57723]

Greetings all

Stupid question , where can I buy a mounting bracket for a 700 series Johnston motor , all the sites I have looked up only go up to 600 size motors, any suggestions ?..?

Regards Bryan

[Dave MilbournParticipant @davemilbourn48782]

Marks Model Boat Bits used to make these. Give Mark Windless a ring and see if he'll make you one. **LINK**

DM

[BRYAN ASTONParticipant @bryanaston57723]

Greetings all

I have bought from a local dealer a Etronix Photon SBS sensorless brushless system which consists of 2950kv brushless motor, a 45 amp esc and a program card ,after connecting everything and a 7.2v nihm battery ,fully charged ,with crossed fingers I switched it on, nothing happened apart from esc fan going and flashing lights on esc, no amount of wiggling of throttle lever had any effect. Reading the instructions the programmer is only required if you wish to change the default setting, should the motor run without the programmer.or have I completely misread the instructions.

I can always take it back to the dealer to sort it out but I wanted to get it working myself. Foolish boy,

Regards

Bryan

[Dodgy Geezer 1Participant @dodgygeezer1]

When I read the instructions there are a couple of red lines indicating that calibration is essential for first use, and they talk about things to do when the lights flash.

See here: **LINK**

[BRYAN ASTONParticipant @bryanaston57723]

To Dodgy

Thank you for the link, much better info than the paperwork that came with the kit, motor is now working forwards and reverse, tomorrow I wil plug in the programmer.

Much obliged

Bryan

[harry smith 1Participant @harrysmith1]

Hi Bryan

I have entered into the brushless and Lipo world, but, with the help of club members!!!!

I have been luckily that the help was super great and saved me heaps of money!!!

The club mainly in the brushless and Lipo world use Hobbyking parts.

The ESC which sounds like your problem, we use the car ESC's with reverse from Hobbyking.

These are easy to program with their card.

The program card works on the HK 45 to 100 amp ones.

Also I have found that on the new gear, you TURN ON THE TRANSMITTER FIRST AND THEN THE RECEIVER.

To turn off TURN OFF THE RECEIVER(powers from the ESC) AND THEN TURN OFF THE TRANSMITTER.

Failure to do this upsets the ESC and the binding between the transmitter and receiver.

Also the throttle channel must be in the neutral position.

I screwed up one ESC so bad the only fix was using a servo manual test card to reset the dam thing!!!

[BRYAN ASTONParticipant @bryanaston57723]

Greetings Harry

I have got the brushless motor going perfectly now thanks to dodgys link in his reply to my plea for help, I think if you are fitting your first brushless motor it is all a mystery compared to fitting a brushed motor, or putting it another way you are scared of it in case you mess it up.

The instructions with my kit say the default setting is ok for most occasions, you only need to use the programmer if you want to change the default settings, when you get your head round it , it is fairly simple ,as the saying goes when all else fails read the instructions

I will be using 7.2 v nihm batteries only , it seems to run ok on them and I have a lot of nihm batteries.

When it stops raining I will try the boat in the water and if required I will change the settings, watch this space.

Thank you for your reply

Regards Bryan

[harry smith 1Participant @harrysmith1]

Hi Bryan

The first ones always the hardest!!!!

I rewrite my own instructions and posted my car ESC setup a number of times to help fellow members!!!

[BRYAN ASTONParticipant @bryanaston57723]

Greetings Harry

You are quite right, this was my first attempt that was successful and with all the horror storys that I have read I expected the worst, it didn't burst into flames or explode .

I have another brushless motor that I that I bought months ago ,never did get it to run, I'll try again one day.

Onward and upward.

Bryan

[mark69Participant @mark69]

Hi just a thought but ,my brushes motors in my planes have to be set up as follows .. Throttle lever set to full ,then plug into the batt and a series of bleeps that sets the top end parameters move throttle to lower position another bleep ,that sets lower end and the motor will not move that is now set but there is a failsafe built in is that every time you have to start with the trottle in the full up maybe you hadn't armed the ESC ??? ,mark

[harry smith 1Participant @harrysmith1]

Hi mark69

The car ESC's have reverse so the default is in the middle neutral position and the Hobbyking one's do not have end parameters, but, their HK-IA 6 and IA10 transmitters have these and power curve setting.

Hi Bryan Aston

It is nice to success now and again !!!!

[BRYAN ASTONParticipant @bryanaston57723]

Thank you all for your hints and tips, I hope fitting a brushless motor into a boat that ran perfectly well with a 700 series Johnson motor on 12v .will be worth the expense and aggravation , only time will tell, as I previously said watch this space.

Regards

Bryan

[BRYAN ASTONParticipant @bryanaston57723]

Greetings all

Finally fitted a brushless motor to a much modified Sea Commander ,I tried programming it with supplied gizmo , got it going problem in the garage took it to the lake it moved about six yards or meters if you like and suddenly slowed down to crawl ,just made it back to bank then dead as a dodo, nothing, zilch. I slunk off home tried it again in the garage worked perfectly for a while then zilch again, took it back to the hobby shop in defeat and they reprogrammed it and it ran perfectly, obviously pilot error on my part.

Went the lake yesterday switched on without much hope and it went like a bat out hell, success !!, joy.

I have heard that brushless motors are difficult to control at a slow speed , I experienced no problem at all, just as good as a brushed motor as an added bonus the batteries lasted a lot longer than usual.

So don't be afraid of brushless motors they are easy to get going if you know what you are doing, I obviously did not.

Bryan

[BRYAN ASTONParticipant @bryanaston57723]

Sorry about the missing words,they are no,the,of, in that order, I must proof read before pressing post in future

[Dodgy Geezer 1Participant @dodgygeezer1]

That would be the Etronix Photon set that you mentioned earlier? Could you tell us which size motor it is?

[BRYAN ASTONParticipant @bryanaston57723]

Dodgy

It was indeed the Etronix photon 2950kv motor, I will try it again with a 9.6v next.

[Dodgy Geezer 1Participant @dodgygeezer1]

Posted by BRYAN ASTON on 14/03/2016 20:53:01:

Dodgy

It was indeed the Etronix photon 2950kv motor, I will try it again with a 9.6v next.

 

Eltronix seem to have a whole range of motors, several at 2950KV – **LINK** You might have the 10, 15 or 20? And I note that they are in-runners – I have usually seem out-runners advised for boats, since they have a higher torque if used without a gearbox.

Moving to 9.6v from 7.2 is approximately moving from 20k rpm to 30k rpm. I predict that the engine noise will get quite shrill…!

Edited By Dodgy Geezer on 14/03/2016 21:55:51

[BRYAN ASTONParticipant @bryanaston57723]

DG

If you look down the Etronix list the motor I used is a ET0415 and is an inrunner, as you know most if not all brushless motors are for cars or aircraft, I have six boats and non of them have gearboxes I have never seen the need.

I have only been building boats for around two and a half years ,most of them scratch built and I have found them fairly easy to build but I keep them simple life is too short, I have only built one kit the SS MEDEA and it almost drove me mad, never again.

The performance of the Sea Commander is now equal to that achieved previously by using a 700 series Johnston motor running on 14.4 volts ie.2 nihms in series quite fast enough for most lakes/ponds I think, I only fitted a brushless for a change ,I doubt if I will use another one, but who knows

Bryan ( a complete novice in this hobby)

[BRYAN ASTONParticipant @bryanaston57723]

Greetings all

As I have had such a success with the fitting of a brushless motor into my Sea Commander I have changed my mind and am considering fitting one into my 44 inch Huntsman, has anyone got any suggestions for a suitable motor with matching speed controller with reverse and programme card, any help would be welcome.

Yours in anticipation

Bryan

[Author]

Posts