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[sonarbell]

Ok Guys..Some help if you don't mind..

I have recently acquired a 34 inch Huntsman from a very generous member on here and I'm looking to use a brush-less motor setup.

Any clues as to what sort of motor power, prop size and battery pack I should be looking for.

Thanks in advance.....

[boatmadman]

I reckon a brushless outrunner at 1000kv on 4s lipo's with a 35 to 40mm x2 prop should make it go well enough.


When you look for the motor, look at the power output as well as size, you will need something in the region of 1000w


Ian

[sonarbell]

Hi Ian

Thanks for the info..

Its pretty much where I was in my thinking too.

Just one thing I need to clarify. The LI'PO batteries have a "C" discharge rating ??. What does this mean ?

Regards

James

[inertia]

This is the highest current which can be supplied by the pack continuously. The C is the value of the pack's capacity, in amps, so a 2600mAH pack has a C value of 2.6. If the discharge rate is 25C then the pack will supply a current of 25 x 2.6 = 65 Amps..........but not for long!   
DM

[sonarbell]

Thanks Mr DM..

[Time Bandit]

Depending on the speed you want to reach I´d use something in the range of a 40mm "race" prop, 35mm seems too small to me.
"race" prop since most good looking brass props do not perform very well at > 6000 rpm.
If it´s available try to get a Graupner "K" 42 mm. These are the best plastic props I know, even if used fully submerged.

800-1000kv at 3-4S seems also good to me (depending on the speed you want it to go).
I´d use a 35 mm outrunner with ~150g weight (probabaly 3542) for 3S use and a 42 mm (should be > 200g weight) outrunner for 4S.

[Leaky Bottom]

Hello
 
I've got a 31" huntsman and the set up I use is a Hyperion Z3025-08 motor ( 985 kv ), X45 plastic prop running on 3s 3000 mah lipos
 
Gives very good performance but I would go for bigger capacity batteries for longer duration, I use these as they were what I already had.

[sonarbell]

Thanks again for all the advice..

Another question Grasshopper 

I have a Spektrum DX6i with 6 channel receiver. Will this be acceptable or should I look at getting something else. ?

Ta muchly 

[Netleyned]

Nowt wrong with the Spektrum 

Ned

[sonarbell]

More info required chaps..

If I keep my Graupner 750 Jumbo motor what size ESC and Batteries would you recommend ?

Cheers muchly

[canabus]

ESC I am using a 60A with reverse and a 5800 mah 60C 3S battery with a 40mm x 1.4 pitch prop.
About an hours run time.
If you get an ESC which handle 4S plus batteries, change the battery for a cheap performance increase.
I have a Hobbyking 3639-1100kv but the D3548/4 1100kv would be better(handles 4S).

[boatmadman]

I think you would be much happier with her performance if you went brushless, lighter and more powerful.


Have a look at the thread huntsman refurb where I did up a 46 inch version.


http://www.modelboatmayhem.co.uk/forum/index.php/topic,46524.0.html


I think an outrunner, about 1000kv on 40mm prop and 4s lipo should do the job nicely on this smaller version.


Ian

[red181]

The question,
I have a Huntsman what prop motor etc etc etc comes up time and time again, and the answer always seems to be based on a few who have experienced the same thing, and therefore can give solid advice, but, most have all wanted different things, run time, speed, different technology such as lipo, brushless, so the answer is never clear to give, its based largely on budget and building skills, and what you want as the final outcome

You would probably get a more balanced judgement by reading previous posts on the same subject, trust me there are a lot, did you look at previous posts prior to asking the question, which has probably been asked several times in the last few months alone. Unfortunately as its asked so many times, you only get a few responses, but there are many more answers to the exact  same question, its worth just going over them

[sonarbell]

I have read and re-read all the topics regarding the different set-ups. Technology moves on and sometimes new ideas might be discovered after the various project re-builds and new builds of this particular model.

If you don't ask you don't get as they say 

Any way I have purchased some propulsion gear for the model..I think I may have over-specced the items a tad 

Time will tell eh 

[canabus]

That's what ESC's are for, that's if cannot help yourself in seeing what she will do!!!
Our club members have a number for boats which will go well over they scale speed.

[martno1fan]

Don't use spektrum on water unless using the marine rx or you could have serious issues with losing signal as spektrum doesnt like water.Might be ok for slower models but anything going fast i wouldnt risk it without the specific marine rx,s.
Mart

[JimG]

As long as the aerials are kept above the waterline there shouldn't be any problems with loss of signal.

Jim

[essex2visuvesi]

Don't use spektrum on water unless using the marine rx or you could have serious issues with losing signal as spektrum doesnt like water.Might be ok for slower models but anything going fast i wouldnt risk it without the specific marine rx,s.
Mart

Never had a problem with mine and I use the "cheap" Orange Receivers.
As the others have said as long as you keep the antenas above the waterline theres no problem


My huntsman will stand on the Transom if you are to heavy with the throttle.
Theres a partial build log on the forum somewhere

[canabus]

I am using the Hobbyking Turnigy TGY-I6 AFHDS 6 channel which handles 20 models(one at a time)with separate names and setups for each model.
Because I already had the Hobbyking car ESCs with reverse and the programme card, I use them in my boats.
I set the start power precent to 10%, the advance timing to highest and the reverse force to 25%.
This gives me a nice control start off and limited power in reverse(great for getting weed off props in the middle of the pond.
The car ESCs have a cooling fan on them and work better at slow speed when the boat ESCs do not get the water flow to cool them.
The BEAST MOTOR Hobbyking B36-50-07S 5000KV 1100Watts ESC 100A 2/3S Battery.
On 2S=37000rpm.
On 3S=55500rpm.
I have one of these motors, but, I think I need a BIGGER BOAT!!!!!! 

[sonarbell]

Just for a laugh...Here is what I have bought...

42-58 500KV Outrunner.
5S1P 5000mAh Li-Po
Aquastar 160A Speed Controller.

Prop to be decided, but the biggest one I can swing underneath the beast

Please dont be too harsh on me 

[red181]

serious set up! excellent!

My Huntsman 28 (avatar) runs a 1000kv scorpion outrunner, 6 5000mah cells, castle creations 120a esc through a gearbox that is belt driven. I can easily change the ratios depending on the size of lake so I can have fast acceleration or top speed.

I did extensive testing with a eagle tree data logging, the prop makes quite a difference, not so much to top speed, but amp draw, which affects heat and run time. I tested with cheap plastic "x" props to arrive at the best compromise between speed and run time, then gave the results to Simon at prop shop, and he made me a cleaver style 3 blade prop. It took 3 attempts to get it right, but now its 10 mins run time(pathetic really, but great fun) and 24mph, which isn't race speed, but then this  is a 6kg 4 foot ply boat.

I use a spectrum DX6i transmitter with cheapo orange receivers, never had any problems as my boats are not low in the water like racing hulls so the receiver is well above the waterline. I can understand in  a true racing hull, low down, there could be problems with some 2.4 receivers

Good luck

[sonarbell]

Hi Red181.

Thanks for all that info.

I am also going to use a DX6i.

Did you modify the Left Hand Stick or have you left it standard ?..

Thats if you use the Left Stick for Throttle ?

[red181]

Yes I sent it to horizon hobby.  it was a couple of quid to get them to make left stick self centering