Von Ohain

<rant>

Why is torque tube supposedly better than belt drive? Who said that?
I'm currently on my 3rd torque tube tail in less than 15 flights, just because the pinions will strip once the tail touch anything but thin air (yes literally).
How can you fly anywhere but on perfect asphalt without touching anything with the tail?
And what makes this an "upgrade" from belt drive?
My old belt drive tail is over a year now, and it has never ever stripped anything, since it actually has alloy pinions!
How can plastic torque tube be better than alloy belt drive?!?!?!?

If you want to waste money on your Trex 500, pay more for less, and get a torque tube!
If you want something that works, reliably, get belt drive.
I can seriously not se any advantages whatsoever to torque tube.
That torque tube supposedly is "better" is just creative marketing.
Its bull****!

</rant>

gi1mo2

I have both, and do like the Torque Tube best. The tail does touch grass from time to time (I can tell because the blades are green instead of white now).

Von Ohain

How do you feel any difference? The blades is identical, the drive ratio is identical, and if you got proper tension on your belt, there is no difference in free play in the transmission of either of them.
The only difference is every time my tail rotor makes a "SKRTSHH" Noise, then the torque tube will make a "UIIIIIIIII" noise, and the tail rotor will stop rotating.
Unlike the belt drive, which will just chop up whatever is in the way...

(To clarify my style of flying, I don't tell that my tail touch anything by discoloration. I tell by all the leafs that fly off trees after I have been into them, flying. Yes, literally.)

Red Baron Gary

My Feedback: (59)

The torque tube is much more efficient and responsive. I updated my 450 from belt to tt, batteris no last longer, remain cooler after a run.
To keep the tail rotor from fiinding the weeds to soon look for a Musono skid on the web. It is 15 mm (just enuf) longer to keep the rotor from the hard stuff.
Gary

Rafael23cc

My Feedback: (6)

Neither is better than the other, they are just two ways of providing power to the tail rotor. And as you found out , both have their good and bad. A properly set up belt can be as good as a torque tube. There must be a reason why the Yamaha engineers put a belt on the RMax.

I suspect that because of your flying style and flying location you will benefit from having a belt drive instead of a torque tube. Don't get involved in the hype of rc helicopter upgrades, you can go broke if you do.


Rafael

Von Ohain

Thanks for input guys. I'm not enough of a pilot to notice any difference, so I will stick with the stuff that works for me.
Less is more, simpler is better.

madmorgan

My Feedback: (2)

the only differance i see is that its easier to work on the tt's when having to remove and reassemble  and personally i think the tt is more weight . when are they going to make some 6061 gears . imho thats what would make tt's nearly bullet proof .

Von Ohain

They can't do that, and thats the downfall of TT.
Notice that the alloy pinion on the motor drives a plastic pinion on the main shaft.
And the alloy pinion drives the nylon belt drive, but the driven pinion on the tail assembly is plastic, even though is both sitting on the same shaft.
Metal never meets metal when it comes to RC copter drivetrains, and the reason for that (at least I heard) is that rubbing metals makes radio noise, and thats bad for weak radio systems.
And that also the downfall for TT as I see it. Small pinions shall never be plastic, its just too weak. But on TT it is plastic. And it shows on durability.

Red Baron Gary

My Feedback: (59)

Good point there, Von Ohain. But more than that, metal to metal makes for various sizes of metal particle dust to whirl about inside the canopy and find its way to crbas and bearings. From a electronic standpoint metal to metal does not make a lot of electrical noise that would be much of a bother at the frequency our radios operate on.
Gary

madmorgan

My Feedback: (2)

im thinking the reason they dont use metal is because there should be a weak point somewhere and better a gear give out rather than the motor etc who knows why but there again a smidgen of grease on metal gears and you would see very little if any metal particals .

Tinkman

Agreed. You need a point of failure to prevent everything from being damaged in a crash. Kind of like a crumple zone to protect the rest of the components. Better a $7.00 main gear than the entire CNC head for instance.

Joaquin

Von Ohain

In my experience with belt drive, this "crumple zone" tends to be the main shaft spurs.
Which firstly can take a lot more abuse than the TT pinions.
And secondly, they are a lot easier to replace than the TT pinions.
So in my opinion TT is still pointless.
I much rather have my main gears fail from a "dead stiff" tail, than having my tail fail from intentional weakspots in the drivetrain.

Plus, if you got a dead stiff tail and your main gears fail, you can still autorotate with a functioning tail.
When your tail fails, you are just doomed.

I still don't get it, Belt is better, and "crumple zones" in the TT makes no sense.

Red Baron Gary

My Feedback: (59)

The "weak" point I have found with both rex 450 and 500 E helis is the bevel gear that drives to the tail seems to shed teeth much more often than the rest of the tail drive system.
Have owned TT 30 and 50 helis, broken belts are rarely a problem, usually end up with a bent tail boom, maybe the tail blades. Have lsot the two red pressure rollers that maintain belt tension on the oustide (the ones inside the frame) of the TT drive belt a couple of times too.
Fwiw, TT now offers a T tube conversion for the new design nitro X-line of helis.
Guess its a matter of choice.
Gary

Rob2160

I havethe TT on 450 size helicopters and have 3 of them on 450 Pro clones (Hobbyking)

They have been extremely reliable and very tolerant to small tail strikes, (IE Long grass) I have one that has over 600 flights with no issues and the outer portion of the tail rotors are green from grass cutting..

I think they are smoother and feel more responsive in flight..

I also have two 550 size Gauis, a 550 Hurricane (belt drive) and an X5 with is TT, the X5 tail is much more crisp and precise (using the same tail servo on both)

With good lubrication the TT mechanism has less friction.. my TT helis will windmill very easily in extremely light winds, but the Belt drive 450s generally don't.

Just my experience, but I like TT much better. (its also more realistic... I used to fly real helis so psychologically i prefer TT drive)

Von Ohain

I see the point of less friction, thats an advantage to TT.
I haven't noticed any difference in the feel of the control, personally. But it might be just me not being enough of a pilot.
And after having ruined 3 tails in so few flight, I'm very convinced that belt drive is a lot more robust, which I never had any failures with.
I generally have tailstrikes all the time. Small stones from the dirt road I fly from, long grass, leaves etc etc.
Sure a real heli don't have to be expected to regularly survive tailstrikes, but a RC heli actually has to, in my opinion.

Rob2160

Yes,I have to agree, if you are having regular tail strikes with solid objects then the belt is far better.. my 450 helis with belt drives are also all very good and reliable..

BarracudaHockey

My Feedback: (11)

I dont think one is more responsive than the other.

About the only physical difference in flight I can plainly see is during autos where the TT less drag. Even that isn't all that much.

TakeshiSkunk

Pretty sure belts are actually significantly more efficient. Regardless, I prefer torque tube. I don't like having to tension the belt and worry about if I have it set just right, the only time my blade 400 went down was due to tail failure in flight because the belt went slack.

I've never touched my tail on anything since my first flight. Everyone made me all paranoid about it reading around the forums but I really don't understand what's supposed to be so hard about keeping the tail off of the ground, especially with that big old fin. You'd have to come down sideways or something...I can't imagine how chopping through a bit of tall grass could possible strip out your torque tube.

BarracudaHockey

My Feedback: (11)

I can assure you of two things.

TT is more efficent.
Stripping gears by dinking the tail is not at all uncommon

TakeshiSkunk

The efficiency issue just seems odd to me because there's so much less contact with a belt. At any rate, I'm sure I'll probably strip my tail out next time I fly just as an act of karma haha

BarracudaHockey

My Feedback: (11)

Power transfer efficency depends largely on setup, too tight and you're dragging down the system and or burning something up. Too loose and of course it can slip in flight.

The efficency difference is easy enough to prove using simple battery run times and autorotation testing. Even a well setup belt isn't as efficent in energy transfer as a torque tube though.

Don't get me wrong, I have both and prefer the belt simply because, on the Trex the gear that strips is never in the tail, you always have to dig the one out of the frames