bad main hub? or one way gear?

[Khop1839]

Hows it going guys,

so i've been on multiple forums for the past couple of weeks with bogging issues with my brand new e5.  I'm sure some of you have seen a couple of the threads.  Originally i thought it was a problem with the motor, so i had posted in the kde section.  then i posted in the synergy section on HF just to get some input there.  I've tried everything.  and i mean, i've tried tuning the motor/esc in every possible way, even been in contact with patrick from KDE, nothing was helping.  I even bought an RPM sensor and switched to an external gov and that didnt help.  So today i was down at the field and i realized that after i land, when the head is spooling down, the main gear and motor continue to spin until the head stops.  and when i pick the heli up, the hub/one way bearing is locked, so when i spin the head, both motor and main gear still spin.  then after sitting on the bench for a few mins, it frees up.  but i also noticed today, that when i was spinning the head with my hand, it feels bound up for about half way through the revolution.  So i'm beginning to think that its the one way bearing/main hub. 

Does anyone have any ideas?? i've been dealing with this issue since day 1 and the heli is only about 3 and a half weeks old.  I love the flying characteristics and how locked in the heli is, but i have to baby it everytime its up in the air because of how bad it bogs.  and the ESC comes down hotttttttttttt, like really hot.  so i know that this bogging issue is putting a hurting on the ESC and motor, and i'm sure its killing my packs as well. 

Is there any way to get in contact with the factory and maybe get them to send me a new one way, or main hub?  i mean, the heli is really only 3 and a half weeks old, so there should be some way they can help me out right??

any info would be greatly appreciated!

thanks a ton guys,

Kyle

[Scott Anderson]

That sounds like the characteristics of a locked one-way bearing during shut down but don't understand how it would cause any bogging in flight? However there are some great people here with vast experience and knowledge to help find the problem with your E5

Great thing about this forum you do get to interact with the factory !

[flyalan]

From my experience the only time I have seen that particular behavior is if the bronze bushings are not fully seated in the hub. Did you red or green loktite them in place? If they are not seated fully or cocked at a slight angle the will cause binding. It is unlikely that the one way is actually faulty.
I helped a very experienced modeling with the same thing at Birmingham this year. We ended up heating the bushings and tapped them down gently. Fixed it!

Also be sure you are using oil and nit grease in the one way bearing.

Cheers
Alan

[Khop1839]

Yeah, I took the hub apart and those Bronze bushings are in there the way they are suppose to be. I had my buddy over looking at it with me and he has a brand new e7se.... Virtually the same hub design and we are both stumped. The only thing that makes any sense to us is a faulty one way bearing. I have no idea at this point. Very very confused and frustrated.

[flyalan]

Yeah, I took the hub apart and those Bronze bushings are in there the way they are suppose to be. I had my buddy over looking at it with me and he has a brand new e7se.... Virtually the same hub design and we are both stumped. The only thing that makes any sense to us is a faulty one way bearing. I have no idea at this point. Very very confused and frustrated.

Did you remove the bronze bushings and check the one way? If not I suggest you do so.  This is the only way to determine if it is actually the one way bearing.


Alan


Alan Butler
Team Synergy

[flyalan]

Another thought.  How does the sleeve fit in the bronze bushings?  Insert the sleeve from both sides just a couple of Millimeters and turn the sleeve.  Are they tight on the sleeve.  Turn the sleeve while inserted.  Does the sleeve possibly feel out of round? 
I know you feel that the bronze bushings are correctly placed.  What I would like you to try is this...
Get a block of wood and a deep socket that is close to the outer diameter of the bronze bushings.  Lay the hub on the wood and heat the exposed bronze bushing with a blow torch.  This will loosen the loktite.  It needs to be very hot.  Use the socket to tap down the bronze bushing into the hub. Use a good bit of force.  LEt it cool and do the same for the other bronze bushing.
It does not take much of a misalignment to cause some binding of the sleeve in those bushings.  They are designed to be a pretty tight fit.


Cheers
Alan

[Khop1839]

So you want me to heat the bronze bushing up while it's in the hub??

[flyalan]

Are the bronze bushings loctited in place?  If so yes then use the procedure I outlined (with the bushings in place).
What you are trying to accomplish is the be sure the bushing are completely seated in the hub.  If either one is canted
even micrometers off then they will cause binding.  The reason for the heat is to soften the locktite.




Alan

[Khop1839]

oh, the bronze bushings are not loctited into the hub. 

[flyalan]

Then pop them out and verify they fit the sleeve well. And check the one way fit while they are out. If both are okay then one or both of the bushings were likely not completely seated.

Alan

[flyalan]

Also you do need to loktite them in once this is sorted out.

Cheers
Alan

[Matt Botos]

Kyle,

Send me an email at matt@mattbotos.com I have some ideas about your configuration.

Can you tell us what head speed and pinion you are using?

Also, if you can't figure out the auto hub send it back to me. I would be glad to inspect it.
The auto hubs are sufficient for large 700 electric power so a lockup on the E5 is not typical.

Thanks,

Matt

[Kevin Feil]

Kyle,

 Always remember, if your flying the Synergy Product "ALWAYS" come to this forum to post your questions/ Concerns and get the answers your looking for. Although HF and RR have a lot of Visibility however you will get answers quicker and most importantly "Correct Answers" to your questions.. Good luck and Matt will get you all squared up..

Best Regards,

Kevin

[Khop1839]

I really appreciate all the help guys.  It makes flying this awesome machine even better knowing that you have this type of support behind you.  I just sent matt and email and i'm taking the hub out right now to look at everything.

Ill post with an update here shortly.

Thanks!

Kyle