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svond
08-27-2005, 01:35 PM
A AXI 4120/14 motor in the cowl of a Great Planes C182 (.40 size) is really going to get wet from the prop spray, I fear. Any experiences?

Stan

fdix
08-27-2005, 04:03 PM
I’ve got a BN-2 Islander from JRmodels powered by 2 AXI 2208/34. It has several flights now including a landing when one motor got rather wet… If you don’t fly in salt water a few drops now and then should be no problem.
After you take off the motor has all the time to dry and after landing it will still be a bit warm, so eventual drops of water evaporate rather quickly.


Do some testing to see if the motor gets seriously wet, if it really does you'll have to raise the undercarriage.

nick.wright
08-28-2005, 02:56 AM
I have an outrunner from Balsa Products on a slow stick float plane that has been dunked several times. The water doesn't seem to hurt the motor any, but I have fried a speed control. A little hot glue and some better landings has solved the ESC issue.....

bc-slowflyer
08-29-2005, 07:17 AM
I had an Aurora 400T outrunner break off my Hydrofoam and sunk in 20 ft. of water for about 1 hour. I blew it out with compressed air and then srayed it with methol hydride and then let it dry in the sun all day. The next day I mounted it back on the Hydrofoam and when I advanced the throttle the motor sounded unbalanced at lower rpm's. After 5 minutes of gentle running it eventually quit. The CC 25 was OK but the motor would not turn over. The bearings are good and the motor turns over by hand but not with battery power. Any ideas? Anyone want to take a stab at rewiring this 400T?

Thanks;
Rod

fdix
08-29-2005, 12:49 PM
I had an Aurora 400T outrunner break off my Hydrofoam and sunk in 20 ft. of water for about 1 hour. I blew it out with compressed air and then srayed it with methol hydride and then let it dry in the sun all day. The next day I mounted it back on the Hydrofoam and when I advanced the throttle the motor sounded unbalanced at lower rpm's. After 5 minutes of gentle running it eventually quit. The CC 25 was OK but the motor would not turn over. The bearings are good and the motor turns over by hand but not with battery power. Any ideas? Anyone want to take a stab at rewiring this 400T?

That’s strange… Have you inspected the windings?

electric mike
08-29-2005, 08:59 PM
A brushless outrunner would be much more insensitive to water exposure than a brushed motor. If the brushless outrunner have been submerged in salt sea water, rinse it immediately in regular household water to remove the salt particles, let it dry, perhaps with the aid of compressed air and then if possible put a small amount of oil on the ball bearings.

A friend of mine got two small brushless AXI's submerged in water after the wing folded on a Twin Aventura, the both ESC's fried themselves due to the active circuit with the battery connected, but the motors remain in excellent condition.
Needless to say, the both brushless ESC's let the magic white smoke out, and we all know what that means....

/best regards from Mike

Wattwhere
09-01-2005, 01:53 AM
I'm buiding a GWS E-sarter to flly off water with GWS floats.
Has anyone expeerience with using the supplied motor and power supply?
Shall I plan an upgrade to a brushless motor and LiPO power while building?
Thanks

bc-slowflyer
09-01-2005, 03:47 AM
I'm buiding a GWS E-sarter to flly off water with GWS floats.
Has anyone expeerience with using the supplied motor and power supply?
Shall I plan an upgrade to a brushless motor and LiPO power while building?
Thanks

If you can, upgrade to a geared brushless motor (Himax 2015-4100 with C or D gears) and a 10X8 prop or equivalent and 3S 1500 lipo. Two of us have identical planes except one has a stock brushed motor and mine has the Himax. It's like night and day. They are both on floats. Mine loops effortlessly and easy rolls with the floats on!! Take off with the Himax is about 10-15 feet.
Hope this helps.

Rod

lindart aviation
12-06-2005, 03:23 AM
Dunked a BP12,ESC stayed dry,plane set back on water and flew out the pack....

r_kopka
12-06-2005, 11:53 AM
...then srayed it with methol hydride and then let it dry in the sun all day. The next day I mounted it back on the Hydrofoam and when I advanced the throttle the motor sounded unbalanced at lower rpm's. After 5 minutes of gentle running it eventually quit. The CC 25 was OK but the motor would not turn over. ...What is "methol hydride" ? Can it destroy the insulation of the windings ?

RK

TRASHBUG
12-10-2005, 01:37 PM
I have been told by mulitple sources that a product called corrosion X (http://www.corrosionx.com/) is a good product for preventing water damage to electronics. I have never tried it personally but sounds like a good plan for any kind of electronics that will be around moisture. They are soaking their components in the stuff and letting the excess drain out. You will need to clean the exterior with alcohol if you are using foam tape, hot glue, velcro etc to stick stuff in place.

meatball
01-02-2006, 06:06 PM
Corrosion X is one of the best corrosion preventatives out there, hands down. I use the same stuff on my jetski engine after rides. Never tried it on an electric engine though, I'd make sure that the type you use DOESNT conduct electricity though. The marine stuff is usually used for protecting metal engine cases, not electronics. But I dont see why it wouldnt work awesome.

ragbag
01-03-2006, 01:51 AM
I don't do sea planes, but I have race gasoline powered boats.
They do flip,,,,, it is when not if?

I was told by a Futaba rep to drop the servos in alcohol and let them soak, dry out and they should work most of the time.
At the time I was using all Hitec and the only ones that never survived was the big 700, they are Surface mounted electronics and are instntly zaped with water.
The other Hited's, for insurance we put a bit of plumbers grease on the shaft, slipped an o-ring then the arm. Throttles and small rudders were no problem.

The 700 on my big offshore boat were my down fall.

Receivers were put in big balloons and a peice of foam around the seros wires. The air trapped in the balloon kept it dry.

The alcohol worked on all the other servos that we had dealings with. Today I would put two sevos on the rudder, might dig that boat out and try it again. Got rid of the hydros and others.

By George

Evo
01-04-2006, 04:32 AM
I had my e-starter dunked too.... Maybe this should be a support group for e-RC float pilots...

I was running a himax 2025/4100 on a 1:4.4 gear. 9X5 sport prop.

completely dunked the nose. Took the motor out left it out in the sun and let it dry for a few hours... put it back in with no problems.

all elecs were in baggies, including the battery.

People in this forum have mentioned methol hydride I'm not sure what that is but I have bought metholhydrate at the home depot and Canadian Tire. I use metholhydrate for cleaning stuff when I need it to evaporate fast and not leave behind any resedue. doesn't evaporate as fast as acetone but it about 2-3 times faster than 99% ispropyl alcohol.

WARNING: if you are cleaning with 70% alcohol... Most 70% alcohol is cut (diluted) with distilled water (or so they claim)... I've had 70% alcohol leave residue behind (looks like a haze on a supposedly clean surface)

Gonna try the floats on snow soon :)
Cheers,
Dan

BradT
01-04-2006, 06:47 AM
Fresh water won't harm the motor, as long as the bushings or bearings are relubed after drying out. The rx and esc are the parts that must be kept dry. I once saw a flying boat, with a pylon mounted brushed motor, flip while landing on water. The pilot simply used low throttle to power up the submerged motor and prop to taxi the inverted plane back to shore!
Brad.

joeycoates
11-20-2006, 05:17 AM
I have done the same with a GWS Tiger Moth when wind flipped it over on its back! I gave it some throttle just to se what would happen and it pulled it back to a shore. (Not exactly where I had been standing, but I had no directional control)

donjiskra
11-20-2006, 07:29 PM
Stan,
"Corrosion X" is just what you need!!!
Spray it on ALL your electrical components and stop worrying.
It really works, believe me, I know, after totally dunking 3 planes, (with outunners), all suffered NO after effects.
Happy fret free flying.
Don

Stuart B
12-26-2006, 12:03 PM
A couple of my work colleages ran an out runner while it was underwater (fresh).

It ran fine. The even drove it harder than it was rtated for I beleive, the water is much better at cooling it down.

The only thing that will be bothered is the bearings.

Stu

cyclops2
12-27-2006, 02:32 AM
The other sore spot is the steel laminations of each pole stack. As they rust the airgap increases and efficiency drops.
Also as the stack rusts it will become longer and put pressure on the windings insulation. This can cause intermittent shorts in any phase and be difficult to find.

xray328
12-27-2006, 07:04 PM
Don't some people recommend you break in motors (can't remember if its brushed or brushless) under water?

cyclops2
12-28-2006, 02:39 AM
Yes. EVERY major electric motor company runs all AC & DC motors underwater till the brushes are seated correctly.

Please have proof of purchase and a picture I. D.


OK.

Stuart B
12-28-2006, 08:14 AM
Yes. EVERY major electric motor company runs all AC & DC motors underwater till the brushes are seated correctly.

Please have proof of purchase and a picture I. D.


OK.

I am not saying this is correct but thought I'd reply.

I did a google search. I found a reference about underwater breaking in on THIS forum in that search.

http://www.wattflyer.com/forums/showthread.php?t=1268

As happens on forums people read things and remember them. Sometimes this results in the spread of some knowledge (Correct or otherwise...not saying this is incorrect....I don't know).

Forums have too much sarcasm.

Stu

cyclops2
12-28-2006, 05:37 PM
You are right Stu.

I read my post today and I think someone with no electrical experience on electric motors will do what I posted.

DO NOT EVER RUN a motor underwater !!!!!!!!!!!!!!!!!!!

You can injure or electrocute yourself if the power is from a wall socket or a battery pack voltage greater than 50 volts dc. Weak hearts and wet hands both start stopping around there. Several welders have died over the years in just such conditions.

cyclops2
12-28-2006, 06:02 PM
If anyone will take a flashlight a look at the brushes on a new 400 motor you will see that the brushes are DELIBERTLY put on the armature the WRONG way!! Why ?

They are restricting the amount of current the motor can pull. Safety ? This prevents a harmless looking little motor from burning out in 2 seconds if overloaded. It also prevents it from ripping hands and fingers apart if a gear mesh is involved. DC motors are torque crazy if near stalled.

A motor can pull 15 to 30 times the amperage if needed with fully seated brushes.
Still think a single 400 size motor would be harmless ? Good design feature. TRY to leave it alone.

moodier
06-01-2007, 03:37 AM
Water imersion,Not sure of the problem here.At least on my 2812s the manual specifys can breakin underwater.They ran fine in a jar of water for breakin!If they can run underwater like that don't see what problem a little dunk in the lake should be??