Model Boat Mayhem
Technical, Techniques, Hints, and Tips => BRUSHLESS Motors and Speed Controllers => Topic started by: drifter_uk on October 29, 2012, 09:07:21 am
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Hi guys just after some info :D Ive been an aero modeller for about 5 year now and done a couple of scratch builds and just recentley decided i want to get into boats due to not getting out much with the distance i have to travel etc
Ive just ordered the Orca plans of Pat trittle and trying to get my head around the power system to be used:confused:
Ive got loads of spare motors and esc of my planes (the exact ones) and just want to ask if i could get away with using them in a boat my system sofar consists of
Jr propo pcm9x tx with frsky 2.4ghz module (of my planes)
2x 3s 5000mah 20c lipos
A2217-6T 1500kv 250watt motor which is a replacement for a 400/480 size motor
Motor Specs:
* Type: A2217-6
* No. Of cells: 2-3S LiPo/8-10 Ni-xx
* RPM/V: 1500KV
* Max. efficiency: 79 percent
* No load current @10 V: 1.0A
* Working current: 22-26A
* Max Current capacity: 28A (60 seconds)
* Dimensions: D28 x L35mm
* Shaft diameter: 4mm
* Weight: 72g/2.51oz
30 amp esc
Specification:
* Class: Brushless
* Model: 30A Pro
* Application: Aircraft
* Constant Current: 30A
* Burst Current: 40A (for 10 seconds)
* BEC Mode: Linear
* BEC Output: 5V/2A
* BEC Output Capability:
on 2S LiPo - RX + 5 standard micro servos,
on 3S LiPo - RX + 4 standard micro servos,
on 4S LiPo - RX + 3 standard micro servos
* Battery Cell Count / Input Voltage: 2-4S (7.4V - 14.8V) LiPo or 5-12 (6V - 14.4V) NiMH
* Weight: 25.8g
* Dimensions L*W*H mm: 55 x 25 x 9mm
any info and assitance would be greatly appreciated
Thanks Les
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Hi,
The simple answer is yes, you can use them. There are things to think about though, the esc has no reverse, (planes dont usually fly backwards), but thats not always a stopper in using them in boats
The motor will rev much higher than you need for a boat, unless you want orca as a fast electric! However, it will only go as fast as you allow it with your throttle control, so that may not be an issue either.
With that motor, you probably wont need to go higher than 2s, that will give plenty power.
Radio system, 2.4ghz is perfect., Otherwise is 27khz or 40mhz for boats.
Ian
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Hi Les,
You can certainly use aircraft brushless motors in a boat, although whether the one you have will be suitable depends on the boat you are building. 1500 Kv will probably be OK, but I am not familiar with the Orca you are planning.
The ESC will also be OK, but we generally use reverse as well as forward in a boat - to stop the boat if not actually to go in reverse. I believe the Fast Electric boats don't have reverse, and if your Orca is this style then the ESC will also be OK. There's no harm in trying them anyway - you can always change the ESC later if you find you need reverse.
Hope this helps.
Barrie
PS Ian beat me to it, but we both seem to be saying the same thing :-))
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Agree with the others above with one further note
Aircraft/helicopter speed controllers and motors are designed to have air flowing over them to aid cooling. In the confines of a boat this doesn't happen so they can overheat
It can be overcome by watercooling
The motor can be cooled by either a watercooled mount, cooling coil/jacket or both
Cooling coil
(http://www.cornwallmodelboats.co.uk/acatalog/3325_1.jpg)
Water Cooled motor mount
(http://www.offshoreelectrics.com/prodimages/509b14-540-adj-water-mount-front_medium.JPG)
The ESC can be upgraded to watercooling by using a water cooling block in the heat sink
(http://www.cornwallmodelboats.co.uk/acatalog/3329_sml.jpg)
These can be easily found online from the likes of Hobbyking and ebay
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All these answers are looking promising and all I can say is thankyou to everyone that has replied there's only one way to find out and that is to try the motor and esc that I've already got I'm new to boats so I'm learning as I'm going just the prop I need to sort out now then my power system will be sorted
Thanks Les
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I forgot to mention that copper* brake pipe found in cars makes for a good motor cooling coil
*may or may not be copper as has been discussed at length before
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I forgot to mention the motor is an outrunner so will be difficult to cool with those 2 options so would have to run uncooled but the model will be scale so max speed of about 14 mph not a lot of speed but the orca was designed by pat tritle to have a Dumas 6v high speed brushed motor and a 2.5 mas gearbox
So think I should get away with it also I'm going to disable the bec on the esc and run separate as they tend to generate a lot of heat from experience with my planes
Thanks Les
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The watercooled mount in colour is designed for outrunnerd.
Ned
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The motor is fine but I would consider gearing it, its RPM will be too high for the Orca even on 6 volts and a small prop,
ACC3407 Promax 400 7.2V w/2.5:1 Off-Set
Gear Box[/size][/font]
[/size]
http://www.maxxprod.com/mpi/mpi-10a.html (http://www.maxxprod.com/mpi/mpi-10a.html)
Your motor should bolt straight to it though the one I have is 3.2 mm shaft which is what a 400 usually has, any other gearing with 3:1 ratio will do the job as well of course
With the 2:1 ratio and 7.2 volts will give 5500 RPM
With the 3:1 ratio and nominal 12 volts (your batteries) will give the same RPM approx, perfect for a 40 mm prop and no water-cooling should be nessesary, should only draw about 3-5 amps
Cheers
Nick
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The watercooled mount in colour is designed for outrunnerd.
Ned
thanks for the heads up with the mount ned I think i'll get one of those ordered nearer the time of installing the motor etc because im still waiting for the plans to turn up to crack on with the build
Thanks Les
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The motor is fine but I would consider gearing it, its RPM will be too high for the Orca even on 6 volts and a small prop,
ACC3407 Promax 400 7.2V w/2.5:1 Off-Set
Gear Box
http://www.maxxprod.com/mpi/mpi-10a.html (http://www.maxxprod.com/mpi/mpi-10a.html)
Your motor should bolt straight to it though the one I have is 3.2 mm shaft which is what a 400 usually has, any other gearing with 3:1 ratio will do the job as well of course
With the 2:1 ratio and 7.2 volts will give 5500 RPM
With the 3:1 ratio and nominal 12 volts (your batteries) will give the same RPM approx, perfect for a 40 mm prop and no water-cooling should be nessesary, should only draw about 3-5 amps
Cheers
Nick
Hi nick thanks for the link to those gearboxes I think i'm going to try run without a gearbox as i can adjust everything on my tx like rates/travel etc and for the £600 price tag would expect to get all these features :P but if it doesnt work out i'll put a gearbox in
Thanks Les
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Hi LesI always try to set 100% throttle as the maximum speed Ie match the prop speed and motor as closely as possible[size=78%] [/size][size=78%]regardless[/size][size=78%] of any programming in the TX[/size]
If it works for you that's OK as well :-)
Nick
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Hi LesI always try to set 100% throttle as the maximum speed Ie match the prop speed and motor as closely as possible[size=78%]regardless[/size][size=78%] of any programming in the TX[/size]
If it works for you that's OK as well :-)
Nick
Thanks nick I'll bear that in mind its just i don't want to buy unnecessary parts if i don't actually need them but i have got another motor but don't know if it will be overkill i do know its lower Kv per volts
Type: BL2220-07
* KV: 1200
* No. Of cells: 3S Li-Po
* Nominal Current: 25A
* Maximum Current: 31A (60 secs)
* Dimensions: D28.5 x 37.3mm
* Shaft diameter: 4mm
* Weight: 81g
* Recommended ESC: 40A
* Recommended model weight: 800 - 1800g (1.7 – 4 pounds
Thanks Les
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That motor on 2 cell would definitely be better than the 1500 Kv ok2 I like the 1000 Kv version of that motor for my springer tugs
Cheers
Nick
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That motor on 2 cell would definitely be better than the 1500 Kv ok2 I like the 1000 Kv version of that motor for my springer tugs
Cheers
Nick
That motors in my Tony nijhuis 62" spitfire and its got some grunt about it on 3s but if that will be better suited I'll just pull it out of that as i don't really use the spitfire much but I'll see what happens when the build commences
Thanks Nick for all the help
Les