Sheered Motor Shaft!

Keylitho

Keylitho

New member
Does anyone know why this happened with this motor? I thought they were stronger than that. It is a Electrifly Ammo 4300 in a Typhoon 3D

The only thing I can think of is that the motor had too much tourque for that plane.

And I am sure that the mesh was very smooth and not tight at all.
 

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I've never seen that problem before. Try hitting the red button on your Interlink controller. That should reset it.
 
You could have been using the wrong prop and putting too much load on the motor, possibly overstressing (and overheating) it. You also could have been using too large of a battery pack and making the engine do more than it should. You know what I mean. I've done that in my earlier days of flying. I've had about two shafts break on me. Another wild possibility is your prop may have loosened and caused some damage, but I doubt that would do it. You'd have to have an awfully crappy shaft. You also could have just bought a dud motor.
 
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Well It's the aftermarket 2300 lipo for the typhoon I am thinking that mabey I did have the wrong prop on the thing... Hmmm that bum's me out I just got that motor.
 
The Typhoon 2 is supposed to come with the ESC correctly programmed for the motor that the plane comes with.

However in actual practice, the ESC tends to revert to the programming for a outrunner motor ( instead of inrunner ).

This makes the Typhoon seem to "skip" a gear at low throttle settings, even though nothing is actually slipping or skipping.

That ratcheting you hear at low throttle is the pinion gear abruptly being stopped, which throws a lot of torque on it.

At high speed the problem is still there! Only worst, and it can and will cause the same problem you had, a broken shaft!

Download the E-Flite documentation for the 25Amp ESC and you'll see how to correctly program the ESC.

The timing MUST be set for inrunner motors, or you will have the same problem again with a replacement motor.


Been here myself, done that. discovered the problem, fixed it.

BTW: It took me two replacement motors and two gear assemblies before I finally figured out what was going on.
 
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I've seen that happen once before. The prop touched the ground during an attempted landing, then took off again. Two minutes later, the shaft broke. It was summized that it was due to the prop being out of balance.
 
opjose said:
The Typhoon 2 is supposed to come with the ESC correctly programmed for the motor that the plane comes with.

However in actual practice, the ESC tends to revert to the programming for a outrunner motor ( instead of inrunner ).

This makes the Typhoon seem to "skip" a gear at low throttle settings, even though nothing is actually slipping or skipping.

That ratcheting you hear at low throttle is the pinion gear abruptly being stopped, which throws a lot of torque on it.

At high speed the problem is still there! Only worst, and it can and will cause the same problem you had, a broken shaft!

Download the E-Flite documentation for the 25Amp ESC and you'll see how to correctly program the ESC.

The timing MUST be set for inrunner motors, or you will have the same problem again with a replacement motor.


Been here myself, done that. discovered the problem, fixed it.

BTW: It took me two replacement motors and two gear assemblies before I finally figured out what was going on.
Click to expand...

Actually It's the Original Typhoon 3D with the 20 Amp brushless speed controller.
I don't know if that makes a difference... But I flew the thing for about two batteries worth and then on takeoff of the third charge snap 2 ft off the ground.. I am just glad it wasn't higher. I did not hear any ratcheting. The thing was running smooth and clean and way stronger than the stock motor.
 
AFAIK the problem is the same with the brushless setups on either.

Though your experience may be a different problem.
 
Yeah, looks like the shaft fatigued. Look very closely at the break and see if the surface looks crystalline in appearance.
 
Haole said:
Yeah, looks like the shaft fatigued. Look very closely at the break and see if the surface looks crystalline in appearance.
Click to expand...


If by crystalline you mean a little sparkly in spot's then yes it does kida look that way... What does that mean?
 
In simple terms, that the metal shattered. Likely started as a microscopic stress fracture from too much torque.

Real airplanes crash this way too when little things like, oh say, wing spars decide to get tired.

Carl
 
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