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Serpant
02-07-2006, 07:31 PM
Hi, I have just got a Ripmax Spitfire. I wanted a plane to play with when i went away that i could just fly anywhere. I have never had any luck with electric planes and have not used one for over 5 years.

I hoped that with the passing of time my luck would change. I got the following set up

Ripmax 600 spitfire
Tornado 40 amp brushlass esc
Tornado 3630/1000 brushless motor
8 cell 3700 gp 9.6v sub c

I was using a 11 x 8 folding prop.

I put four flights on the plane with a flight time of about 6 mins. On the fourth flight the motor stopped early. After looking over the plane i found that the heat shrink covering the esc had melted off. The esc still worked but if i went over half power the esc smoked.

Overlander have exchanged both the motor and esc today. They say on there web site you can use up to a 12 x 8 prop. Now they say that was a mistake and the motor was over proped with a 11 x 8. With a 10 x 6 prop the spitfire is so slow.

What is the best way forward? What prop do you recommend? Is what i have bought ok or have i got the wrong gear?

Any advice most welcome.

Paul

Sky Sharkster
02-08-2006, 05:18 AM
Hi Paul, welcome to Wattflyer! First I have to say that I'm not familiar with Tornado products, is that a brand in the UK? In any event this problem sound like your motor/prop/amp draw is excessive for the 40amp ESC. Is there a way the shop would let you exchange the replacement ESC for a larger one? I'm pretty sure that would solve your problem. If the plane will only fly properly with the larger prop, and your battery is capable of supplying the power, the ESC becomes the weak link in the chain. A couple of questions; Are you running at or near full throttle most of the flight? Is the battery very hot at the end of the flight-too hot to hold? The 40 amp rating may be for short, full power bursts only, so if it's run at full power most of the flight, it's being overworked. In the worst case, it will melt, shutting off not only the motor but the receiver and servos also. I leave it to your imagination what will happen next! If you can test the amp draw on a wattmeter you will get a better idea of what's going on but from what you've said, my bet is the ESC needs to be upgraded, a 50A continuous rating should be enough.
Good Luck!
Ron

watt_the?!
02-08-2006, 07:01 AM
why not go for a 10x8 prop then?...it will havea faster pitch speed than your 11x8 prop so should be faster....you could probably go for a 10x7 to be as fast as your 11x8 setup in fact....just less thrust.

Tim

Serpant
02-08-2006, 09:37 AM
Hi, battreys do not get that hot. The new motor and esc have been fitted now. I will get a 10 x 8 prop and try it. The motor came from www.overlander.co.uk (http://www.overlander.co.uk)

Should this motor pull the ripmax spitfire round ok. I am disapointed with what i have as it all came highly recommended. It cost over 300 and it does not seem that good. I met a guy at the flying field Sunday with a 75 model that total out performed my set up.

Paul

watt_the?!
02-08-2006, 10:04 AM
how heavy is your plane?

there are so many factors...ive seen a cd rom motor power a depron plane at 80mph...is that out performing your plane?...

i think not. its a mix of plane weight, size, flight time and much more.

Tim

Serpant
02-09-2006, 08:58 AM
My plane all up with battreys is 3 pounds in weight. I know there is depron planes out there that will out perform what i have, but i did expect with the set up i had, that it would at least fly with some vertical performance.

Paul

watt_the?!
02-09-2006, 09:08 AM
Hi Paul, can you tach your 12 x8 prop setup please?

all i can do is do some math, and hopefully we can identify the issue- if any.

i get about 1:1 thrust/weight for your setup- which is good going.

the best you'll see is 50mph with that motor/battery/speedy.

Tim

Serpant
02-10-2006, 08:59 AM
Hi, tried a 10 x 6 prop yesturday, as the model shop said that the prop i used last time was to big. The speed controler fried in 2 mins. I have taken it back to the shop. I have asked them to get me an axi motor and castle speed controler. Lets hope that fixes it.

CorsairJock
02-10-2006, 01:44 PM
Next step: Li-Poly battery pack. A 3 cell (11.4 volt), 4000 mAH or so Lithium Polimer pack will weigh very significantly less than the NiCad or NiMih pack you are using, possibly about 1/2 pound.

Foamer
02-11-2006, 01:18 AM
you will need the Li-Poly battery pack