Dang it.... a NEW gear failure

[Finless]

Pirnaha had this problem too.
My second flight today I though my ESC cut out. I was letting HF user fireup fly my heli and he had to auto it in... Thank god he wasnt low inverted or something. No problem getting it down.

Back at the bench I discovered the metal gear that the auto bearing is press fit into split and slipped on the auto bearing :arggg: :arggg: :arggg:

This is not the first report of this happening..

We looked at the gear and a Fireup being a machinest (he owns K2 machines company) determined that the gear is not hardened or if it is not enough. He did a file test and using a file you can tell by how the metal flakes off. Sure enough it is not very hardened steel.

Also the wall thickness on this is REALLY thin.

I am going to get some more gears and Fireup has a oven for hardening steel. We are going to take a crack and a couple of hardening techniques and see if we can get this thing more durable.

Anyway letting you all know to watch for this for sure if your powering up with a hotter motor.

FYI here is the pic from Piranha showing the failure. I could take a pic of mine but it is only cracked and hard to see and a picture wouldnt show it.
http://b0.imgsrc.ru/p/piranha/3833644fmV.jpg

Bob

[ChrisT88]

Pirnaha had this problem too.
My second flight today I though my ESC cut out. I was letting HF user fireup fly my heli and he had to auto it in... Thank god he wasnt low inverted or something. No problem getting it down.

Back at the bench I discovered the metal gear that the auto bearing is press fit into split and slipped on the auto bearing :arggg: :arggg: :arggg:

This is not the first report of this happening..

We looked at the gear and a Fireup being a machinest (he owns K2 machines company) determined that the gear is not hardened or if it is not enough. He did a file test and using a file you can tell by how the metal flakes off. Sure enough it is not very hardened steel.

Also the wall thickness on this is REALLY thin.

I am going to get some more gears and Fireup has a oven for hardening steel. We are going to take a crack and a couple of hardening techniques and see if we can get this thing more durable.

Anyway letting you all know to watch for this for sure if your powering up with a hotter motor.

Bob

If this becomes a regular issue I'm sure Adrian at Revo Co would be interested in doing up a run of hard ones, although we haven't experienced any issues with 500mm blades. We haven't tested 550's yet but we plan to. Maybe they are the breaking point.

[AdrianM]

The wall thinkness is a problem. Let me know how your tests come out bob.

[Finless]

Adrian, I was looking at it this again this AM. If the hardeneing doesnt solve it then I see two other solutions.
1) Increase the height of the gear to cover the entire auto bearing. The extra material maybe enough to keep it from splitting

2) Change the mod! If course this means changing the mod of the main gear AND the tail drive gear.

Now all I need is a few gears.

JOHN.... got any is stock???? I would like about 3 to test different hardening techniques. water hardeneing, slow cool hardening, and oil hardening.

Bob

[odieser]

Bob is it possible that without building a entirely new heli that you guys are pushing the limits with power beyond the hurricanes possibilities
Is this the way the Trex 450's and others got better

[Finless]

Is this the way the Trex 450's and others got better


YES! The Trex first version went through all kinds if issues like this when we started to power them up. Exploding tails, failing auto bearings, sloppy head system (was HDE then), exploding main grips, etc....

I keep saying this heli has a lot of potential ONCE all the design issues are fixed for setting up higher power. Stock the design is sound with 1900 hs. WE ARE pushing the current design limits. I am confident Gaui will get this stuff resolved especially since they will have thier own 1100 KV motor coming.

Bob

[odieser]

okay I was just curious
I am enjoying my stock heli as I am new to this and find it great now for what I am asking it to do
So when you guys get it all figured out perhaps I will then require all the upgrades
In the mean time keep up the good work and I will be watching with interest
Thanks

[Turbojoe]

Hey Bob. Just a thought. Maybe change the heading to say "different" gear failure. When I first saw it I thought Adrian's gears were failing already.

Joe

[AdrianM]

Changing the module will solve the wall thinkness issue.

[Finless]

Changing the module will solve the wall thinkness issue.


Agreed... thats why I suggested that ;)

You going to have a go at that Adrian? Might be actually better long term than trying to get the gear harder....

Bob

[arclite5]

I'm enjoying this to be honest ;]

It's like.. Every couple days you run into a problem, and the next day you have several ideas for it, and then the next day you've implemented a fix. R&D baby!

With all of these skilled people; Finless, ReadyHeli, Chris, Adrian.. And the guys who have been contributing behind the scenes.. This helicopter is going to get really good really fast. I'm excited.

-Kyle

[AdrianM]

Thats great but Gaui sure is enjoying a lot of free R&D from us. I hope in the end what come around goes around. :dontknow

[AdrianM]

Bob - I can make the gear but I will need a good source of one way bearings to press them on to. The are cheap for Gaui and Align becuase they buy thousands. If I buy one way bearings are pretty freaking expensive (~$15.00ea).

I will look into it on Monday.

[dutch_anykey]

Same here Kyle :D

And the best part is that we can look over their shoulders and see what they are cooking in this R&D kitchen.
It's better then getting an answer like "we are aware of this problem, we'll get back to you in a few weeks"
I wish GAUI would be a bit more like that. I understand that several new things are coming from them in the near future. But we don't hear too much about it. But then again, maybe they are not into tweaking this bird too much and focus on stock configuration.....

Keep it up guys :D

Maurice

[arclite5]

Haha.. What's cookin;? Smells like progress.

I agree with Adrian about the free R&D thing.

-Kyle

[modelholic]

I agree with Adrian about the free R&D thing.

-Kyle

Yes - up to a point. No doubt Gaui are watching these threads with interest but, and isn't there always a but, they can't really be blamed for failures when the design is being pushed beyond the standard setup. We expect high performance vehicles of any type to suffer an increased failure rate. I would be pretty annoyed if my car needed a new engine every 1000kms or so and yet this is often beyond the working life of racing engines. Fundamental design issues need to be addressed - the short links being one example. That is a given. The rest, well, that depends upon the design parameters they (Gaui) have established.

What I can appreciate and would also be annoyed at is if Gaui released the heli WITH THE EXPECTATION/INTENT that users would effectively field test their design and offer the fixes required. That is then very cheap R&D, at best poor etiquette and at worst exploitation.

Obviously just my opinion - any comments welcomed!
Simon

[AdrianM]

Like Bob said this all happened to the Trex 450 when it first came out.

[Tom Viper]

About the auto gear, Gaui had the first run of gears made with to small tolerances. This problem "should" be fixed by now. I friend of mine has also blown 2 of these gears using the Z30. While mine is still holding up, using the same motor. So, last I heard, Gaui had allready fixed this issue. Exept for the people trying out the new Z70 motor... :mrgreen: I got the latest M1110 motors from Gaui, and the new HP gears. These are being tested in about 2 hours... allready mounted on my Hurry.
Should be fun to see if they will cope with me Z30 power!

[Finless]

Gaui had the first run of gears made with to small tolerances. This problem "should" be fixed by now.


My kit was suppose to be the new one with the proper gear. But it still cracked. It's didnt bust up like other juts a crack.

Adrian, users can push out the old auto bearing and push it into the new mod gear so you dont need to sell them with the bearing. Also I think this is the same bearing as the Trex450? I would have to go look. Remember the 450 has a main shaft sleeve to make the diameter larger! I am pretty sure it's the same bearing (not 100% though) and people can buy the new German Align V2 bearing too!
They can also use the cheap Align bearing removal tool to take it out and put it in!

Personally I dont like the mod being used by Gaui. I prefer the mod you are using.

Bob

Bob

[Piranha]

Hi guys,
Bob I'm really very much regret about your broken gear, I have already broken 3 of them :(
Yesterday I have serious crash, damaged the half of my heli! I was making loops and during the third loop when I was inverted, heli suddenly cut out! I made a flip and try to auto but there was no enough rotor inertia so another crash!
You can see broken auto gear
http://b0.imgsrc.ru/p/piranha/4169856KxX.jpg
The frame is destroyed from both sides :(
http://b0.imgsrc.ru/p/piranha/4169860PGq.jpg

When it was happen, I was 100% sure that it was cut out(I switched back from align ESC back to GAUI) and i was sure that the gear was broken due to the collision with the planet , but now I AM NOT SURE :(

And I think that GAUI NEED to sent us :hug: NEW HELIS FOR FREE for our FREE R&D work!!! :bomb:

(Sorry for my English)

[ozace]

You guys are so keen. I love your enthusiasm for this machine.
Gaui certainly have released plenty of upgrades so far and i am sure there are more in the works.
I love the ride, please keep it up. :noteworthy

[tornet999]

I have had one sharp cut off with fresh lipos with the GAI 50A ESC (new version marked GAI), really terrible to crash due to malfunctioning material. Anyhow now I am using Align 75 ESC and that one is working great.

Why did you change back to GAI ESC ?

[Piranha]

I swiched back to gaui cause I use 7S A123 Battery and on align ESX you can only set 3.6V cut out(lipo safe low) but for A123 I need to setup this setting to as low as possible voltage or even disable cut out at all! And using GAUI you can select 5v cutout setting

[Finless]

Bummer on your crash Piranha.... Looks like you need a new frame set now :(

Bob

[tungym]

I think you got the 1st batch of one way bearing (cracked steel gear) like me. For the 2nd batch , the one way bearing is not loctite well and result in slippage. The 3rd batch is ok and had been served me for the last 60 flights.

Yes, I agree that a thicker 1way bearing gear and thicker main shaft/ rear gear can solve most of our problems.

Piranha, why not just disable lipo LV cut for A123 :arggg: I time the flight accurately before it runs dry.