Brushless motors for subs? - Using brushless motors in subs

[chuck chesney]

Is anyone using brushless motors in their subs? The size and power of the brushless units seem ideal for use in small and confined places, like WTC's. If there is any experience with the brushless motors for boats, what are the plus and minus points. Also, what exact motors (by name and model, if possible) are the equivalents of a Speed 400, or a Dumas/Pittman motor? It's very difficult to find any information on an exact unit per unit replacement.
Thanks, subguys.
Chuck

[aeroengineer1]

I am getting ready to

I am getting ready to use a feigao (I think that is how it is spelled) in my little boat, but the thing had to be equiv to at least a 350 sized motor. It is their 12mm x 22mm motor. It is really small and the esc is a nice size as well. I like it. If I can get done with all the homework that I have, I will get to finishing it.

Adam

[tsenecal]

Chuck,

I am using the following

[color=#000000]Chuck,

I am using the following in my Dave Manley Blueback, and have had excellent results with it]http://www.horizonhobby.com/Products/Default.aspx?ProdID=EFLM1300[/url]

they make several other models that have higher rpm ratings, but the sub runs faster on this motor than it did with the original graupner speed 400.

in addition, I am using the castle creations mamba ESC, and a kokam 2100mah 2 cell lipo for the battery.

In my sub, the combination runs the sub at scale speed for 1.5 to 2 hours per charge.


I have also used a himaxx HC2212 in a small 15" scale model of a USCG 41' utb as a direct replacement for a speed 400 with massive improvement in run time.

the feago that adam speaks of is a 4000 rpm per volt "inrunner" type motor, which if used without gear reduction will cause a submarine to act more like an excocet. the original speed 400 that i replaced in the USCG was a 1800 rpm per volt model. both of the motors i have listed are "outrunners" and behave much more like the speed 400 in speed and wattage.

I haven't found any specs to back this up, but outrunners also seem to have tons more torque than the brushed motors.

lastly, I haven't found anything in the brushless world that has the same wattage/rpm rating as a pittman. you may have to go with a motor of ample wattage, and a gearbox. I am thinking 400rpm per volt at the final shaft would be equivelant to a pittman. I suppose something like this should work, with a 2]http://www.horizonhobby.com/Products/Default.aspx?ProdID=EFLM4032A[/url]

I have no idea where one would find a 2]



Edited By tsenecal on 1160843334

[chuck chesney]

Adam and Tim, thanks a

Adam and Tim, thanks a million for the detailed information. I am in the process of building a new WTC for my subs, primarily for a much modified Engels Patrick Henry, which is 53" long, and has been running as a wet hull, RECABS boat for several years. The brushless motor concept has had my interest for a couple of years now, since there is no motor sparking, with it's inherent EMF generation, as well as high power, high efficiency and small size. The brushless motors seem like a natural for subs, but until I read your posts, had trouble in trying to match motors and ESC's in a way that made sense when comparing brushed/brushless motors. Thanks again.



Edited By Chuck Chesney on 1160848545

[anonymous]

You are correct about outrunners

You are correct about outrunners having more torque.

I also have a link that may be of interest to builders of larger subs or anyone using 500+ size motors(ie Speed-540 or Speed-550)

http://www.castlecreations.com/products/mamba_max.html

This motor and speed controller combo is completely waterproof and is available in 3 torque/speed ratings, the 4600Kv has the most torque which im assuming would be the best for a sub, it does about 27'000 Rpm while under a moderate load and 56'000 Rpm no load (both at 12V). With the torque it has it could eaily drive a prop at a 1:1 ratio or direct drive. (this motor was intended for cars and it is THE most powerfull one out there unless you go to a system bordering on $1000)

The 4600Kv and the 5700Kv are capable of running on 12V but the 7700Kv has a maximum of 10V before it gets VERY hot, VERY quick (if you know what I mean...).

As I said I am new to submarines and have decided on a 4' model of an AKULA and will be powering It with the "Mamba Max 5700Kv" motor and speed control at 12V and will hopefully be able to do a jump out of water.

I am new to submarines but am very versed in electronics, robotics, RC Aircraft, RC Tanks, RC cars, Rc Boats... Well just about everything RC but Subs.



Edited By MRunhart on 1160871138