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afterburn 549 01-13-2014 08:28 AM

I do appreciate everyone's concern and input..
However if you knew what i was dealing with you would readily see its a NO brainier.
The way its all designed,..It is designed to fail. (and MANY have) serious.
The factory to solve it went from a 30 MM shaft way up to a 35 MM .... BIg DEAL
The shear loads from jack shaft to Main shaft break them at the bearing from the stress
A straight in design would be ideal like R22.
I am NOT the only one that has done this...
just i want to do it a little cleaner to solve the problem
There are people that have converted these to turbine Pwr with no problems, BUT
the did get rid of the crap ( Kiss Aviation )
Its hard to post over on their " Board" as "we" that want to change from the caveman to something better is regarded as outlaws of sorts.
Its a catch 22 not a R22 LOL
Anyway thanx for the help.....

porsche4life 01-13-2014 11:03 AM

Listen to Seahawk, he is a very wise man with more time around birds than the rest of us combined. If he says it won't work, I'm inclined to believe him. ;)

afterburn 549 01-13-2014 11:33 AM

YOO Ok......
It has all ready worked for other people.
OMG you guys .If you were around the wright Bro would have never got off the ground......!
Its kind of interesting you will poo poo what you do not even know what you are being negitive about.
All most too funny

afterburn 549 01-13-2014 12:52 PM

found it
SUBARU REDRIVE
I think something like this then a 90 deg gear box (ring and pinion) to gear down rest of the way .

gordner 01-13-2014 01:42 PM

There is room for innovation and improvement in almost any design...

afterburn 549 01-13-2014 01:54 PM

Yup
Hence the "freeze"
Plus, when there are other agendas aboard......leaves lots a room !

Flieger 01-13-2014 05:15 PM

I wouldn't expect a planetary gear to be any more reliable than a (well designed) intermediate shaft.

afterburn 549 01-13-2014 05:30 PM

The shafts break!!,
Has 6 belts to it, a 20 pound chain on top, plus HUGE sprockets to gear it dwn some more.
Bearing temp stickers on each bearing because they run too HOT . (and BREAK ) ( to monitor after the fact (cause you can not see them in use )
More belts to accessories .....
plus more stuff.
Maybe a "well" designed one would work, but they all are under worrisome watch full eyes .
The key word would be a well -"designed one."-
With as much effort to replace ( and EXPENSE ) it might as well be tossed.
A new one is 3500 bucks , and now back to Sq one to repeat all the above *(if you live through it)*
So, why repeat the same mistakes over and over.
I think thats the definition of stupid ?... or crazy ! ?
I would think a well designed planetary would mean check the oil once in awhile and be done.

Flieger 01-13-2014 05:52 PM

Quote:

Originally Posted by afterburn 549 (Post 7855127)
The shafts break!!,
Has 6 belts to it, a 20 pound chain on top, plus HUGE sprockets to gear it dwn some more.
Bearing temp stickers on each bearing because they run too HOT . (and BREAK ) ( to monitor after the fact (cause you can not see them in use )
More belts to accessories .....
plus more stuff.
Maybe a "well" designed one would work, but they all are under worrisome watch full eyes .
The key word would be a well -"designed one."-
With as much effort to replace ( and EXPENSE ) it might as well be tossed.
A new one is 3500 bucks , and now back to Sq one to repeat all the above *(if you live through it)*
So, why repeat the same mistakes over and over.
I think thats the definition of stupid ?... or crazy ! ?
I would think a well designed planetary would mean check the oil once in awhile and be done.

I mean a shaft which has 2 bearings and 2 gears. A nice large diameter hollow shaft is about as reliable as you can get for power transmission.

A planetary gear set has 3 or so shafts inside it which the planets rotate on. These shafts are smaller and you can't easily inspect them and I am not sure what kind of bearing they might have on them, if any. You hold those shafts stationary and turn the sun and you get a big reduction between the sun and ring gear.

afterburn 549 01-13-2014 10:50 PM

I know you want to steer me in the right direction and i do appreciate that.
The shaft is solid, mounted vertical, a 2 bearing affair with the drive sprocket above top bearing.
It drives a 5 row chain with a master link inserted FROM the BOTTOM so as to keep a eye on the clip be fore use..LOL....the chain i think weighs 20 some odd pounds bathed in oil...above the exhaust
Needless to say......the shaft breaks right there above the loaded bearing .
Right about then you know if you passed autorotation class or not...and even of you do...hope there was a pretty good place to put it dwn.

Seahawk 01-14-2014 06:20 AM

Quote:

Originally Posted by gordner (Post 7854674)
There is room for innovation and improvement in almost any design...

Agree. That is not my issue here at all.

Helicopters are vibration nightmares and many design compromises are made to dampen vibs, which substantially impact the airframe structure in terms of fatigue and stress cracks.

The drive train in a helo must be in harmony with respect to vibration...there are instances where low frequencies harmonics in different flight regimes (harmonics in helicopter change depending of hover, forward flight, etc.) can quickly damage the airframe and drive components.

I can refer to any number of airframe and drive component "improvements" to the H-60 that ended up causing unintended stress on the airframe.

You can also cause what is referred to as "ground resonance" by changing drive components:

<iframe width="560" height="315" src="//www.youtube.com/embed/Cf1N70szHLg" frameborder="0" allowfullscreen></iframe>

The OP can do whatever he wants, not my issues, just don't fly over my house

afterburn 549 01-14-2014 06:30 AM

Mark-18 Helicopter Main Rotor Gearbox.

http://www.glasairproject.com/Marcotte/Page2.html



http://www.epi-eng.com/rotorway_helicopter/rotor_drive_system/drive_system_analysis_contents.htm

afterburn 549 01-14-2014 06:35 AM

Quote:

Originally Posted by Seahawk (Post 7855830)
Agree. That is not my issue here at all.

Helicopters are vibration nightmares and many design compromises are made to dampen vibs, which substantially impact the airframe structure in terms of fatigue and stress cracks.

The drive train in a helo must be in harmony with respect to vibration...there are instances where low frequencies harmonics in different flight regimes (harmonics in helicopter change depending of hover, forward flight, etc.) can quickly damage the airframe and drive components.

I can refer to any number of airframe and drive component "improvements" to the H-60 that ended up causing unintended stress on the airframe.

You can also cause what is referred to as "ground resonance" by changing drive components:

<iframe width="560" height="315" src="//www.youtube.com/embed/Cf1N70szHLg" frameborder="0" allowfullscreen></iframe>

The OP can do whatever he wants, not my issues, just don't fly over my house

Something was lost in rotation there......thats interesting it was flying?
Wonder what came off, or broke?

stomachmonkey 01-14-2014 07:26 AM

Quote:

Originally Posted by afterburn 549 (Post 7855857)
Something was lost in rotation there......thats interesting it was flying?
Wonder what came off, or broke?

<iframe width="853" height="480" src="//www.youtube.com/embed/0FeXjhUEXlc?rel=0" frameborder="0" allowfullscreen></iframe>

gordner 01-14-2014 08:15 AM

Quote:

Originally Posted by afterburn 549 (Post 7855857)
Something was lost in rotation there......thats interesting it was flying?
Wonder what came off, or broke?

Nothing broke, that is the result of ground resonance. Often occurs on wheel mounted choppers when a strut is underinflated, but can occur on any chopper when the vibrations come into tune and build on each other creating a destructive standing wave.

Tim Hancock 01-14-2014 08:56 AM

[QUOTE=Seahawk;7855830

Helicopters are vibration nightmares and many design compromises are made to dampen vibs, which substantially impact the airframe structure in terms of fatigue and stress cracks.

The drive train in a helo must be in harmony with respect to vibration...there are instances where low frequencies harmonics in different flight regimes (harmonics in helicopter change depending of hover, forward flight, etc.) can quickly damage the airframe and drive components.

I can refer to any number of airframe and drive component "improvements" to the H-60 that ended up causing unintended stress on the airframe.

You can also cause what is referred to as "ground resonance" by changing drive components:
[/QUOTE]

I have scratch built and flown my own airplanes... That said, helis scare the crap out of me. As a mechanical guy, I can't get past the small fittings/ linkages/bearings that are involved keeping the whirring blades under control. While I have ridden in quite a few over the years, I view it as playing Russian roulette. :)

afterburn 549 01-14-2014 09:00 AM

After Hueys in nam ...I cant get anymore scared so it dont matter

Seahawk 01-14-2014 09:12 AM

Quote:

Originally Posted by Tim Hancock (Post 7856172)
I have scratch built and flown my own airplanes... That said, helis scare the crap out of me. As a mechanical guy, I can't get past the small fittings/ linkages/bearings that are involved keeping the whirring blades under control. While I have ridden in quite a few over the years, I view it as playing Russian roulette. :)

I have flown over 15 different type/model/series of helicopters, mostly military. There were a few times, especially flying the Kaman H-2F Sea Sprite, when it did get a little Deer Hunter-ish :D

H-60's? Not a care in the world, really...I was going to do something stupid before the 60 would, guaranteed.

To the OP: Your earlier posts on the kits available is really the only alternative in my mind, although this bothered me, from the link:

Note that the airframe-attachment points are not shown in these pictures. They are awaiting final design, and will be completed after we finish the accurate 3D-CAD model of the airframe.

PROJECT STATUS

STATUS: The design of this product is essentially complete, with 3D-CAD components and assemblies, complete analysis calculations, engineering drawings, and some components already manufactured. This product (and the Mark-17 as well) has been acquired by a client company to provide the powerplant basis for a new helicopter product currently in development.


Get the ground run test data and flight test data before you pull the trigger.

I have to ask, do you own a Rotorway?

afterburn 549 01-14-2014 09:24 AM

who is the question directed to?
I have owned a couple R.W.
this one is going to be like Monty Python, now for something completely different
*************************( Or as it SHOULD have been )*************************
I am not doing it their way anymore.!
Is stupid.


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