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[madwelshman]

Hi folks,  I have seen many videos of model boats, where when throttle is applied from stand still, they seem to leap forward.


Is this likely to be simply down to programming and people just using default settings, or is it a characteristic of certain brands of ESC?


I have a few boats that in 1:1 scale are quite fast, Perkasa MTB and a couple of fast cabin cruisers, Fairey Huntsman, Sea Commander and Sea Rover (29" -49") and I want them to be able to pilot them in a realistic/scale manner (most of the time anyway).  A model that leaps forward with only a small amount of throttle input won't look right.




The other thing that I have witnessed is the lack of progression that some ESC seem to have.  Some seem to act like an old 3 plate (Tamiya) RC car resistor type items with noticeable jumps/steps up/down in power each time more or less stick input is given, rather than being smooth and linear.


Again, is this a characteristic of certain brands/types of brushless ESC, using default settings or simply down to users not being smooth?


I have always used ESC from Hobbyking in my planes and found them to be pretty good.


Although I don't know what motors I will be using in each one of them as yet, I will hazard a guess they will need ESC somewhere in the 40a - 80a range.
Can anyone recommend a brand or version of ESC that they have found to be smooth on initial output and linear to given input?
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Thanks in advance.
Will

[tsenecal]

its a little bit of both...  some ESCs are quite aggressive in their setup, some not. some are completely adjustable.

some users are simply using the wrong equipment, putting a high rpm motor, with a "racing" esc into a tugboat.

i personally use castle creation ESCs almost exclusively for my scale boats and submarines, due to the fact that 100% of their parameters can be adjusted using their windows software.

[HMS Invisible]

Brushed and brushless combos function in different ways.

   Brushed motors rated below 30,000 rpm at full throttle & with esc pulse rate greater than 500 Hz (500 x60 =30k) will not resonate and give you a linear throttle response from standstill.

...
Can anyone recommend a brand or version of ESC that they have found to be smooth on initial output and linear to given input?
...

I can't with sensorless brushless technology.
I would also be asking for a cost breakdown and proof of things like "red paint will make a car faster because red cars are faster".

[madwelshman]

Thanks for your replies guys, much appreciated.


Will

[kinmel]

most brushless Esc are programmable and have an option called "Start Mode" or "Punch".
Level 1 provides a slower smoother start to the power curve, while Level 6 gives instant full power, I set all mine to Level 1.

Level 6 usually destroys lightweight  universal joints.

[madwelshman]

most brushless Esc are programmable and have an option called "Start Mode" or "Punch".
Level 1 provides a slower smoother start to the power curve, while Level 6 gives instant full power, I set all mine to Level 1.

Level 6 usually destroys lightweight  universal joints.

Tjank you Kinmel, I thought most half decent esc would be programmable, either by card or with beeps.
I guess there are many modellers who simply install their electrics and that's it.


As long as I can move off from standstill steadily and not instantly getting like 1/2 throttle so the boat shoots away, then I'll be happy.
I presume it's the same with brushless, that the number of poles the motor has makes a difference to how smooth the motor runs at low throttle input too.


Cheers
Will

[kinmel]

This article in Model Boats covers it all very well........    https://www.modelboats.co.uk/news/article/going-brushless/8029

[HMS Invisible]

You get back to this again:-

As long as I can move off from standstill steadily and not instantly getting like 1/2 throttle so the boat shoots away, then I'll be happy.

What about this opinion Will?

Do you understand the important point  that sensorless brushless motors rely on getting a voltage signal to the ESC to do the commutation.
 Lenz's Law means there is no signal at all at zero throttle. 

5 pole brushed + proper ESC will indeed let you creep forward. You can start below 30rpm or 1/2 rev per second.
I'll bet quite a few traders or kit manufacturer that I supplied with 555 motors and escs could put a scientific name to problem but they all knew a target figure for low throttle, what their punters asked for and the cost.
I don't know your target budget or prop or boat but the dutchman gives a more affordable suggestion for brushless esc +attempts a demo of sorts.

[madwelshman]

Do you understand the important point  that sensorless brushless motors rely on getting a voltage signal to the ESC to do the commutation.

Yes, to a certain degree I do.

[madwelshman]

I don't know your target budget or prop or boat but the dutchman gives a more affordable suggestion for brushless esc +attempts a demo of sorts.

As above, my boats vary from 49" MTB, 47", 42" and 34" Fairey Huntsman, Aerokits Sea Rover and Sea Commander.
So all are planing hulls and quite fast.


Budget is realistic, as after quite a few years with model planes, I have a fairly rough idea of the costs of certain items, but as I have numerous boats that I am repairing and converting to brushless, I need to watch the pennies.

[madwelshman]

If I can get esc that I can programme soft start etc into, then great.
I understand that I'm limited to a certain degree by both running brushless over brushed and budget, but so are many others, hense asking the question.
The items in your links are more than reasonably priced and if the ESC is programmable, then should be able to get a half decent result at least.


Thank you.
Will

[madwelshman]

This article in Model Boats covers it all very well........    https://www.modelboats.co.uk/news/article/going-brushless/8029

Thanks for sharing that 


Will

[HMS Invisible]

If I can get esc that I can programme soft start etc into, then great.
I understand that I'm limited to a certain degree by both running brushless over brushed and budget, but so are many others, hense asking the question.
The items in your links are more than reasonably priced and if the ESC is programmable, then should be able to get a half decent result at least.


Thank you.
Will

I always think of the readers of mayhem threads who catch up in the months to come. For those reading 2021 onwards, I have not directly linked to any products. Some dutch fellow with better English has linked to a car ESC on another forum.

Will, I wanted to avoid interpreting what was written on the other forum by Jan (moniker: pomplebed).
I am already thinking his main point can be overlooked if any reader is fixated that there may be a controllable "soft start".

"it still doesn't run very slow"

Furthermore, Punch is a term that conveys positive connotations to a potential customer.
 Having to start in brute force mode won't get into Hobbyking sales pitch but it does describe what the esc has to do in order to start.

[madwelshman]

Thank you very much for all of your input and sharing your knowledge Microgyros, despite having some knowledge already, I still have a lot to learn.


many thanks
Will

[HMS Invisible]

I avoided but wanted to give some supplementary Qs for you to ask.

I think you might get some more product suggestions by a different question or worded differently.
How about this asking for more detail? :-
can anyone list definite, possible or speculative guesses for esc & motor candidates seen online and open to comment?
Have you got or seen reliable:-
Data? Photos?
Videos?
Is it comparitively quiet, noisy, good instructions, already popular, difficult or easy to reverse?Price and availability?
alternatives?
Something you have seen online but hesitate to mention because you have not yet tried out?
Have you anything hidden in a drawer that may or may not fit the bill?
Insights or opinion?

[tsenecal]

this is an 1800kv brushless motor with a 40amp esc, using a 2s lipo battery.  its all about configuring the esc properly

https://www.youtube.com/watch?v=REgvyIkHPFI

[kinmel]

The following parts are popular among those who build model lifeboats because of their high quality, reliability and proven performance.     

Around 1250Kv  provides a 1:12 Shannon lifeboat with speeds between crawling along and scale 30knots when using S3 Lipos.  At full speed it takes 16amp per motor.

Brushless motors......     https://hobbyking.com/en_us/catalogsearch/result/?q=Turnigy%20Aerodrive%20SK3

Esc and the all important programmer......     https://hobbyking.com/en_us/catalogsearch/result/?q=Turnigy%20Marine%20ESC      A 50 or 70 amp Esc works just fine.