>>>> GEAR STRIP YES ONCE AGAIN !!! <<<<<

[HeliFX]

Hmmm as all minicopter owner know by now the frequent gear strip issue.
Well this has happened today on my diabolo with no more then 15 flights on this bird.
Very light 3D flights RPM 1980. Luckily managed too land her safely !!!
yikes having seen this happen to a fellow club member and his diabolo which he has abandon all together for this very reason. Stock Gear btw

I must say my confidence with this machine has dropped a lot and very worried about flying it !!
As I've mentioned this before in other thread with gear strips that I find the backlash on
the diabolo is too much and there nothing I can do to change it cause its by design.
I've even heated the gear on the bench to operating temp to check the backlash and still
find to much of it.

anyone with any good solution or cause to boost my confidence back up or might
have two diabolo up for sale

hope solution is more then "change it too the stronger gear" if that the case it should be standard or add
extra support bracket which should also be standard. Not an added cost

Hope Gerd can chime in and help me out with this one

[Wh1teAfr1can]

Originally Posted by HeliFX

Hmmm as all minicopter owner know by now the frequent gear strip issue.
Well this has happened today on my diabolo with no more then 15 flights on this bird.
Very light 3D flights RPM 1980. Luckily managed too land her safely !!!
yikes having seen this happen to a fellow club member and his diabolo which he has abandon all together for this very reason. Stock Gear btw

I must say my confidence with this machine has dropped a lot and very worried about flying it !!
As I've mentioned this before in other thread with gear strips that I find the backlash on
the diabolo is too much and there nothing I can do to change it cause its by design.
I've even heated the gear on the bench to operating temp to check the backlash and still
find to much of it.

anyone with any good solution or cause to boost my confidence back up or might
have two diabolo up for sale

hope solution is more then "change it too the stronger gear" if that the case it should be standard or add
extra support bracket which should also be standard. Not an added cost

Hope Gerd can chime in and help me out with this one

There should only be minimal lash on that gear. How are the bearings in the upper plate? That is the only way I could see the gear having too much lash. The upper bracket is only for very high power motors where the added torque can cause the primary shaft to flex a small amount.

[HeliFX]

machine is brand new !!
i check every bearing during build.
dry lube also used on gears.
also vents cut in canopy

it seems to me based on how the gear stripped it more
when flexing occurs in the side frames. again I don't know.

gear mesh I feel should be very tight but its not again its by design and nothing I can change

[HeliFX]

Richard when u say there should be minimum backlash I agree completely however as you know the hole and the positioning of all those gear is by design meaning nothing I can do to change or improve it.

unless I elongate the holes in the side frame myself which I don't want to do or should have to do.

sure hope others can shed some light and solutions that have worked !

[HeliFX]

well with the countless other thread on this topic. From those machining there own gears to using Delrin etc

most logically option seems like the extra support
http://www.minicopter.de/catalog/pro...oducts_id=1173

why not make it standard in the kit ?

keep in mind this diabolo was purchased some time ago maybe 1 and half years ago and I'm thinking the newer gear now have a different gear tolerance to improve the bite on those stock gears.

sure would like to have Gerd shed some insight and possible solutions so build my confidence with the diabolo.

[HeliFX]

seeing there a lack of response on this subject. I'm sure a sensitive one at best.

what's up with all the different materials for gear's.

which one ?

all we need is one that works.

[helicraze]

Not sure man. is this machine 12 or 14s?

My first diabolo was awsome, the 2nd was cursed and had tail vibe issues, i sold it at a huge loss after getting new parts from gerd (for free) and problem still persisting, i spent over 12 hrs and even bought new motors and vbars to fix it and no avail.

Maybe this one is cursed like mine was? LOL

[Mercuriell]

Well the gear is stripped because it got too hot, that softens the Delrin and then kerboom. Not saying you've done anything wrong but thems the breaks.

Possible causes, mesh too tight, I know non adjustable.

Too hot under the canopy.

Too hot ambient conditions for your powerbtrain or flying style. I know of three similar cases including yours so it is obviously something Gerd will look at. In your case I'd be inclined to order a Speed Diabolo main gear which should fix it.

[Gerd]

If I see right, only some teeth are broken and placed in the frame window. With an overheated wheel ALL teeth would be flat. Only a few teeth looks like a crash damage.
Can you make a picture from the whole wheel (removed from frame)?

[Mercuriell]

Originally Posted by Gerd

If I see right, only some teeth are broken and placed in the frame window. With an overheated wheel ALL teeth would be flat. Only a few teeth looks like a crash damage.
Can you make a picture from the whole wheel (removed from frame)?

Hate to not agree with a expert but if the teeth are softened then sudden input of power from a smaller steel pinion will surely strip the teeth in the area of the diameter of the pinion due to the inertia of the main rotor.

[TommyBear]

It is interesting that you've only melted a few teeth from the second stage gear.
A close look at your second picture shows the other teeth are still intact.
Below is what an overheated gear looks like,
I've done it on my Mikado and TDR but never on a minicopter.

[thefrog]

Motor looks to be KDE, probably HeliFX wind? Perhaps some heat and lots of power caused that? I would have expected first stage to go if it was just power though.

[TommyBear]

Originally Posted by thefrog

Motor looks to be KDE, probably HeliFX wind? Perhaps some heat and lots of power caused that? I would have expected first stage to go if it was just power though.

Exactly,

The two times I've melted my gears were as a result of using motors that were too hot for the chassis.

[helicraze]

Originally Posted by TommyBear

Exactly,

The two times I've melted my gears were as a result of using motors that were too hot for the chassis.

You really think so? I doubt that, logo and tdr was and has always been due to people setting mesh incorrect.

Man i was flying logo 690 i made years ago prior to mikado on .7mod gear yes .7 mod. With a scorpion motor which is well known for heat

[Mercuriell]

It won't be heat transfer from the motor as is not in continuity. It is too much power for,the tooth area and the strength of the material which is in turn affected by heat. There's always going to be a few users who by virtue of power plant, flying style and many other smaller factors such as blade size and weight .... Very hard for manufacturers to cater for all eventualities !

[helicraze]

Metal gear is no problem id say.

The bit i dont understand is why only a section missing? When ive stripped gears its always happened so quick as soon as part is weakened then the rest shave instantly

[HeliFX]

- Motor in use is a new KDE 4535 ( STOCK ) not rewind for testing !!

- RPM 1980 / YGE 160 HV (GOV store) no external vbar gov

- Mesh being to tight nope the opposite I feel it has too much backlash for this
type of gear cut. Again nothing I can do or change !!

- As the heli being cursed Oh God please no

- vents cut in canopy so in my opinion if it where heat I think I strip more of the gear then just that section. As Gerd mentioned

- the entire gear apart from that section in the photo is perfect not stripped.

- I feel that there was a momentary flex.

- As for my flying style gear stripped during a slow forward flight. my collective management is very good and was do very slow mild 3d in fact first 10 flights low headspeed 1850. Any new machine I take it slow. those initial flights again very slow mild circuits as I had new packs and still working on settings.

- I will provided new photos of entire gear soon

- on all my machine regardless of diabolo I install side frame loose fit and slowly tighten
screw alternating from one side to other side to avoid flexing.
frame is also placed on glass for squareness. gears are preheated to simulate operating temperature during install. zero play on any shafts (shims if needed )

- hoping too hear more solutions if any !!

[HeliFX]

- Gerd any other thoughts or suggestions. I can take a photo of gear alone if it helps
again just that section in the photo is damaged.

- motor temp warm not even hot after each flight enough you can keep your finger on the motor.

- also one important detail. first 10 flights where WITH NO CANOPY

- seeing that gear meshing adjustment is not possible I feel if any gear is removed for maintenance after
use it is important to put gear back exactly as it was.
I usually mark the two gear with a dot and lined them up again.

[HeliFX]

[Wh1teAfr1can]

Can you walk us through what happened when you noticed this? What happened in flight i mean.

The reason i am asking is because typically damage like the can only happen when the blades are stopped which stops the second stage gear, but the motor keeps going. When the gear strips due to improper lash or overheating as posted above 99.9% of the time it will strip all the way around.

The area in the frame where that gear resides is very rigid. Frame flex is not an issue.