super secret thrusted+2 bearing(3 no fit) chinese weight mod

[kahn10]

bench test model mark one......

http://www.helifreak.com/attachment.php?attachmentid=53119&stc=1&d=1214687336

http://www.helifreak.com/attachment.php?attachmentid=53120&stc=1&d=1214687336

http://www.helifreak.com/attachment.php?attachmentid=53121&stc=1&d=1214687336

http://www.helifreak.com/attachment.php?attachmentid=53122&stc=1&d=1214687336

http://www.helifreak.com/attachment.php?attachmentid=53127&stc=1&d=1214687690

ok spun it up with no main blades after balancing parts individually with 0.00 scales.
all good with tracking etc no sign of vibration start pushing up throttle till top rpm still
all good not even a hint of vibration humming along sweetly give her a little tail input
to see how it feels and HOLY CRAP
instant and i mean instant 180 thumb off the stick and instant stop.......
un-****ing-believably fast and responsive

[Drew816]

LIES!!! Chinese Propaganda!!! ;) :YeaBaby: ;) :YeaBaby: ;)

So the 'intent' of this modification is to make the tail rotors more responsive, more quick acting all the way around? I never understood what this mod was all about over in T-Rex land so...

Looks pretty easy, throw on two sets of T-Rex flybar weights, a longer screw and nut and you're all set; that about sum it up?

[mjdee14]

Kahn...

Did you try it before and after as far as how much it took to move the tail blades?

Or did you just do the mod and fly?

Also....what are you using for wieghts....wheel collars...and how are they stacked....?

Longer screw through the outside one, still use the nut to tighten down, another colllar on the back...?


take one apart and post pics of what you used....if possible.

Please.....:noteworthy

[kahn10]

two ticks mike and i'll strip one and take some pics.haven't flown it yet just spun her up without main blades on.when i've done that before i've got maybe 20 or thirty degrees rotation with a little bit of tail input.this time - scarily fast 180 that stopped instantly when i stopped the input.i might need to figure out how to slow it down.....

[kahn10]

right......first drew - the theory.....or why this shit works

when your tail rotors spinning round at a billion miles an hour it creates a force that radiates
out from the point of rotation directly outwards in line with the tailblades called centripetal force as in the first picture.if you turned it around to look at it sideways it radiates equally
from the point of rotation (end of tail shaft) outwards all the way round,but in a single plane as seen from the rear of your chopper (and my crappy picture).
when you apply tail input you are forcing the blades against this centripetal force.the amount your input twists the blades is the angle of deflection.when you look at your tail rotor when its still this is a twist but if you fold your blades while they are twisted it will look like picture B.when your trying to do the sick bastard equations to work out the forces at work here the force to twist the blade against the centri(lets call it c force) is the same as the force required to push the blade sideways against it(if your hub would let it bend that way.don't go there)this force is shown by the big red arrow.lets call it the big red arrow force......wait......na the voices reckon its the deflection force(wish they'd shut up and go away)
http://www.helifreak.com/attachment.php?attachmentid=53189&stc=1&d=1214737322
what your trying to do with the chinese weight mod is make the forces created by the tail rotor to be more like a ball as in even crappier picture number 3.the picture would have to be 3d to make sense so visualize....... if a ball was rotating around the tip of your tail shaft in the same direction as your tail rotor it doesn't matter if you twist it left or right the forces acting on it are all equal.so you still have the centripetal force and the deflection angle but no deflection force......
http://www.helifreak.com/attachment.php?attachmentid=53190&stc=1&d=1214737487
both the centripetal force and the deflection(this may or may not be a really shit name never listen to the voices)force are far greater than the thrust which is just a byproduct of all this happening in atmosphere.if they weren't your blades would fold up instead of creating thrust.so by removing the deflection force you have taken most of the load off your tail servo and gyro.and after the floor test today possibly increased thrust cause **** it piro'd quick.hang on the voices just told me to go and have a smoke.....back in a tick

mike one picture

http://www.helifreak.com/attachment.php?attachmentid=53188&stc=1&d=1214734438

first of all to do this mod the way i have you have to crash a trex 450 lots.and i mean put some effort into it.lawn darts,piro landing and airborne mechanical failure are all acceptable valid ways to gain the necessary parts.the grips i used are stock plastic t rex grips.metal ones would probably be even better.cause they only have a bearing retainer at the hub end of the grip you can fit a thrust bearing plus two standard bearings.(3 was just being greedy) the bearings(and all other thrust set ups it turns out) should from hub to grip go thrust washer large hole,thrust bearing cage,thrust washer small hole,bearing,bearing.this allows the grip to float outwards on the retainer bolt untill the inner bearing retainer surface of the grip captures itself on the thrust washer with the large hole which is also floating.then the thrust bearing can do its thrusty thing while letting the 2 other bearings do their thing with minimal lateral load.hopefully stopping binding.rather than use a bolt for the blade retainers i cut trex main grip spindles to length.i then ca'd and grub screwed a trex flybar weight to the side without the little bolt hole.you have to drill the flybar weights holes to 3 mm.on the other side i enlarged the flybar weight hole so the little standard spindle cap screwhead fits inside it.then screwed it together with cap screw controlling the amount of clamp applieg to the blade.when i was happy with that i locked it off with the grub screw.......and dada.........chinese weight mod.note i just made a lot of this up it may well be bullshit.but its shiny.......

marco

[xodarap1]

i might need to figure out how to slow it down.....
uhm.. remove Chinese weights :confused: :D :)

[Drew816]

Yeah, too much weight so half the amount and see how that affects the setup?

Fly it first, CAREFULLY and record your results. Keep us up to date and thanks for the detailed explanation!

Happy Flying!

[kahn10]

taking her out for as test flight now i'll let ya know how it goes........the slow it down thing was kind of a joke the gyro was actually still is set up for the pre mod tail.the gain in hh was turned right down to speed it up.a bit of electronic tweaking and all should be good.....:smokin:

[kahn10]

quick footnote on why i used spindles on the grips to hold the tailblades.have you ever put the capbolt thru the hole in the blade root by itself.they wobble like drunken bastards.i've got good quality carbon tailblades with brass inserts and their still wobbly as.slide them on to a trex etc feathering spindle and they glide round them with zilch zero nada wobble.....:dontknow

[kahn10]

quick update......half my ****ing homes packed in a ****ing container at the front ****ing door when i went to have a test flight the ****ing batteries in my 8uaps were flat and some helpful ****ing ****ers packed my ****ing charger........don't think i'm taking losing my home very well.death to lawyers and ex's.**** :mad:

[JaggedEdge]

I'm sorry. That ****ing sucks.
I hope things are ****ing brighter for you tomorrow.


quick update......half my ****ing homes packed in a ****ing container at the front ****ing door when i went to have a test flight the ****ing batteries in my 8uaps were flat and some helpful ****ing ****ers packed my ****ing charger........don't think i'm taking losing my home very well.death to lawyers and ex's.**** :mad:

[mysticmead]

Just remember, things will get ****ing better... cause they can't get much ****ing worse... now, tell the ex to go **** herself and then go have a ****ing beer or 6..

[mjdee14]

Call the Mafia....they need the work ? :thumbup:

[kahn10]

well i took her for a hurl and it rocked......had to drop the gain down 5 and i'm going to dial in some expo cause my test pilot took it for a little spin and at the moment i've possibly got the worlds fastest piroing hurricane.might have to rename it the tornado :shock:.......going to try something else as well which might be a goodie for anyone using the upgade plastic thrusted tail grips.you know how their one bearing plus the thrust and kind of sloppy as a retired hooker.........i was playing round with mine and found that the (for lack of technical description) weenie bearing that lives closest to the head block on trex main grips fits perfectly in the recess that the capbolt head goes into just out from the bearing recess.its only about 2 1/4 mm wide so there's still plenty of clearance between the end of the bolt and the tailblade root. think i'll try weenie bearing shim main bearing shim thrust bearing.it gets rid of all that slop :smokin: oh yeah the chinese weight thing......its a go :thumbup:

standard upgrade thrusted slop bucket grip

http://www.helifreak.com/attachment.php?attachmentid=54073&stc=1&d=1215436467

the weenie mark 1

http://www.helifreak.com/attachment.php?attachmentid=54074&stc=1&d=1215436467

[kahn10]

looking over it there's no need for the shim between the weenie bearing and the main radial bearing

[Jungle Bob]

Excellent mental attitude mate! Your life seems to be falling to bits around you and you are concentrating on your Hurri ****ing respect dude, you da MAN.

[mjdee14]

Excellent mental attitude mate! Your life seems to be falling to bits around you and you are concentrating on your Hurri ****ing respect dude, you da MAN.

If most of us don't watch out....with the helicrack addiction, he may just be One step ahead of us in the downward spiral......:badair:

[kahn10]

woohoo....inverted :tongue

[mjdee14]

woohoo....inverted :tongue


inverted what?

:Pics

[kahn10]

One step ahead of us in the downward spiral......:badair:
:lolol

[Milde Shag]

How do I post your Video Kahn ??