Espritmodel.com Telemetry Radio
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Old Nov 26, 2012, 05:04 PM
as much as I can
beenflying's Avatar
NZ
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That tail is the latest vWinRC complete TT tail that sells for about $38 (free shipping).

Yes there are bearings on every joint except the pitch coupling links which only has a bush on the fork side (the same as the V2 plastic link).

The bush looks fine. It's not so important with this sort of pitch control. The bush can only move in one plane (fore/aft), due to slop, and that would have little affect on the pitch, if it did.
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Old Nov 28, 2012, 03:25 PM
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United States, CA, Indio
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Understood, reason I asked is that I just got done doing my 2 450 mongrels with the align vs. modded to belt. One of the bushings in the kits was not concentric, ( drove me nuts diagnosing the problem), one spot,( section actually, caming in, then out ), in rotation of the TR shaft had drag, otherwise flawless. The Align bushing for the dual arm setup is longer than the std. one. Just exploring options for parts.... Thanks, Greg
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Old Jan 10, 2013, 09:12 AM
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Does anyone know of a US source to get these ??
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Old Jan 10, 2013, 10:00 AM
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Originally Posted by rz22g View Post
Does anyone know of a US source to get these ??
tarot-rc-heli.
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Old Jan 10, 2013, 10:02 AM
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They only show them as pre-order.
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Old Jan 10, 2013, 10:16 AM
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They only show them as pre-order.
Send them a email about ETA
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Old Jan 10, 2013, 11:22 AM
OlliW
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Quote:
I think we are starting to make to much rotating mass.
Quote:
I think there's a lot of truth in that! With anything that rotates, such as a heli main or tail rotor, there will be gyroscopic precessional forces, and the heavier the rotor the larger those forces will be, gving the gyro more work to do to counter them.
I don't go with this argument. The rotational mass which may significantly be increased here is that which is rotating around the tail spindle. However, the "rotating mass" which is relevant while moving the pitch slider is that along the tail holders, i.e., around an axis along the tail holder. For a perfectly axially symmetric tail holder there would be only an extremely tiny additional force/torque due to an increase weight of the tail holder, and certainly no gyroscopic forces (the chinese weights break the axial symmetry of the tail blade holders, but supposedly in a favorable sense). So, this can't be the effect. Maybe it's the somewhat larger tail rotor circle, because the tail holders are somewhat larger, though I would have considered this positive (on my rex sport I saw a significant improvement with going from the sport tail blades to pro tail blades)
(PS I am not claiming that the plastic couldn't be better, I am just saying that the rotational mass argument isn't the best argument)
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Old Jan 10, 2013, 06:58 PM
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No I was talking about the entire rotating mass on the shaft not the spindle. The more mass spinning around at 10,000 rpm the more one little flat ball in a bearing or tight fitting has to counter. No amount of chinese weights will help that.
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Old Jan 10, 2013, 07:37 PM
OlliW
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with spindle I meant the tail rotor shaft... sorry for using the wrong word...
(and I still don't go with your argument, my argument is that everything on the tail blade holder which is axially symmetric around the tail blade holder's axis is irrelevant, if it weight 10 or 15 g doesn't matter much for how easily you can tilt the blades or not, hence your effects hardly should be due to too large rotating mass)(in contrast to the chinese weights, those effects exactly come from "breaking" the axial symmetry of the tail blade holder!)(I of course assumed that in your comparison you were refereing to two situations with identical tail blades used)
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Old Jan 11, 2013, 07:40 PM
just gotta mess with it!
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but the Chinese weights (or at least the weights incorporated into the 450 Pro grips) are symmetrical about the tail blade axis - and higher tail rotor weight will lead to higher gyroscopic precession forces, so the ideal would be a zero weight tail.
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Old Jan 11, 2013, 08:17 PM
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but the Chinese weights (or at least the weights incorporated into the 450 Pro grips) are symmetrical about the tail blade axis - and higher tail rotor weight will lead to higher gyroscopic precession forces, so the ideal would be a zero weight tail.
That is what I was trying to get at as well! The ideal would be no weight.

If you look at real helicopters a lot of people have confused the chinese weight mod for harmonic vibration elimination on real helis. Now they do use the principles so they don't need to add that much. Instead of adding lots of weight on a blade they found they can add very little on the axis that would look like a chinese weight mod.
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Old Oct 17, 2013, 04:22 PM
Will fly for food.
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United States, TX, Killeen
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I just had to do some maintenance on my 450 with Tarot Thrusted grips. I re-assembeled it with the thrust bearings on the outside, not the inside.

I did it this way, like we did with the Mini Titan where it was found that with the thrust bearing on the outside, it reduced/eleminated the shakes on spooldown...not that the way the bearings were in the tail caused any shakes (doubtful) but I also think that the thrust bearing on the outside takes the load off the radial bearing and therefore increasing bearing life and it was easier to re-assemble that way.

Thoughts?

Jon
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Old Oct 17, 2013, 05:34 PM
Looptastic!
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Enschede, Netherlands
Joined Nov 2009
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Interesting idea!
Im having some vibration trouble with my hurricane, and could try this. Everything else i tried failed so need more ideas

One thing, you need a shim on the OD of the bearing on the side of the thrustbearing to take the load of, instead of the washer on the ID of the bearing like it is now.


I still have a Tarot thrusted tailass ready to mod for use on my mini-protos for when the stock tail develops problems (gripbearings failing common problem it seems)

I wonder how much it improves the tail.
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Old Oct 20, 2013, 10:29 PM
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Everyone tries to reinvent the mouse trap!
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Old Oct 21, 2013, 10:38 AM
Will fly for food.
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Not trying to re-invent the moustrap. To be perfectly honest, I didn't pay attention to the way the bearings came out and when I got to thinking about it when I re-assembed it I thought about the Mini-Titan's bearing order in the head.

Someone else also put up a good argument about the thrust bearing being on the outside (not necessarily on the Tarot tail grips) in another thread within the last couple of years. It makes sense, it all fit together, the tail is smooth and there is no discernable play...so, why not give it a try?

Jon
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