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[martno1fan]

Ill be using the 190-200 amp esc,s from hobbyking on my large twin build,some people will say there no good but some say theyre good for the money.If you want something a little more reliable then try this one theyre pretty bulletproof from what im told.The outrunner shouldnt need water cooling but it wont hurt to use a watercooeld mount,not sure how much it will actually cool it mind.
Mart
http://www.ebay.co.uk/itm/SEAKING-Electronic-Speed-Controller-180A-ESC-Boat-/180427869753?pt=UK_ToysGames_RadioControlled_JN&hash=item2a0256ce39

[OapPETE]

Thanks Nick do you feel my first choose from Mike will be OK  as I said I don`t need it to fly.

[MikeA]

i was going to say something but my suggestions have been shot down a lot lately. For instance when i first asked you what size propeller you had you said 55-60mm. When i select a motor i allways oversize and that way the motor is hardly working keeping amps down to near no load current. So for my first suggestion i picked the 5055 motor. Then nick said you need a 36 motor, then mart said you needed a t600. people have different ways of getting the same result.  Im not speaking for nick but i think that the motor chosen that nick suggested would be about right, but i would say that wouldnt I

[nick_75au]

Always good to throw out suggestions, the motor and ESC is fine,

Just as another example I have a approx 36" Skiboat hull, I run a 1250 Kv motor on 3 cell and 40 mm Raboesch 2 blade prop the boat draws 40-45 amps flat stick. I tried a 4 cell in it once, the boat got up to ridiculous speed, did a dance on the chines so violently it flipped the 5000 mAH 4 cell lipo and speed controller clean out of the boat that was was a 60 amp controller, a 40 amp or more with the 1000 Kv motor will be fine. a 45 -50 mm prop will be about the right size. This will give you as good if not better performance as shown in Stavros' Perkasa video

Funny thing about brush-less is the motor at scale boat speeds is about half the size of what would be needed in a brushed size. For a low RPM 540/555 a 22 mm(stator size) 1000 Kv has the same power.

Say what you have to say , Its all good, I ain't an expert by any means

Nick

Video's of the skiboat

http://www.youtube.com/user/Nick75au1#p/u/11/lYJtODg_hQk

http://www.youtube.com/user/Nick75au1#p/u/6/qatdSCDpzZI

[MikeA]

Funny thing about brush-less is the motor at scale boat speeds is about half the size of what would be needed in a brushed size. For a low RPM 540/555 a 22 mm(stator size) 1000 Kv has the same power.

Say what you have to say , Its all good, I ain't an expert by any means

Nick

when you mean 22mm stator do you mean the diameter around the can or around the armature?

[nick_75au]

On an out-runner, the bit the windings are on (stator , stationary part of motor)  the motor I'm referencing to is called a 22-20, 22mm diameter 20 mm long, the overall diameter is about 27 mm. I use this in my springer and has no problem driving a 40 mm prop on 6 volts, of which a 550-5 is an excellent match in brushed motors.


Cheers
Nick

P.S on an in-runner, the stator is the can(doesn't rotate)

[MikeA]

but the numbers at beginning are the size of the can of both type right? ive been allways refering like that cos thats how the suppliers are selling them.
for instance this 3542 turnigy outrunner, the drawing near the bottom also says that the outer can diameter is 35 and the lenght of the can is 42.

http://www.hobbyking.com/hobbyking/store/__18231__Turnigy_D3542_5_1250KV_Brushless_Outrunner_Motor.html

does it depend on the supplier how they class there outrunner sizes? like in your case going by the stator 22-20 would be a largeish motor but in say the hobbyking way where they go by the can thats a small one.

[nick_75au]

Yep confusing, it still looks tiny compared to a 500 series motor   I generally go by the Turnigy numbering as that is where most of my motors come from, just happens that the KA22-20 mm is one of the first brush-less I brought.

http://www.kd-motor.com/a22.htm

Some of the Turnigy have a AXI equivalent, Axi which I'm fairly sure use stator sizes as well, the motor in your link is what's in the Ski-boat, and has a a stator size of 28 mm (IIRC)

Nick

[MikeA]

ah i see. i have seen references to brushless motors like that on other suppliers and when it came to matching the model numbers to the motor dimensions it didnt match.

[OapPETE]

Hi, Mike and Nick I have tried to take in all your advice you say Mike you were confused so am I but I am going for the Turnigy 1000cv - 60 amp ESC - 6000-3s battery and the

6478 I Max B6AC charger the more expensive one you said it would cover most battery's as I hope to model for a few years,I assume the can supply me a coupling to fit 4mm to

5mm I am sure my shaft is 4mm, Am I right to order a 6000 battery pack my thought is I will get a longer running time than with a say 5000-3s  or 4500-3s am I correct ? or

wasting money

[MikeA]

yeah the 6000 is the mah and the higher the number the longer that battery lasts. that charger will charge all types of battery. If you know what your doing you can use this charger your charge your battery at the lake side. I dont know much bout that though so cant tell you anymore.

Btw on the battery discription in a blue banner it says :

Turnigy nano-tech 6000mah 3S 25~50C Lipo Pack

http://www.hobbyking.com/hobbyking/store/__11939__Turnigy_nano_tech_6000mah_3S_25_50C_Lipo_Pack.html

Turnigy the make of the battery

nanotech is the model of the battery

6000 is the mah

25c is the draw rate. you take the 25c and multiply by the 6000mah. this gives you 150000ma or 150Amps!

the 50c is the max spike draw rate. this is worked out the same way.

when picking a battery you look at the maxium required for your esc and motor. you then selec what mah you would like then select what C rating you need it to be able to go to. 

[OapPETE]

Thanks Mike I will order these tomorrow night now off to kip. Thanks once again for both you and Nick also the advice from other members I am sure I will be asking you all for more help before long Regards.Peter