600e Pro Tail Blow Outs

[Smoggie]

Originally Posted by watdazit

I presume when you say shim the gears you mean the gear that the torque tube slots into so it pushes the gear harder against its mate?

Yes, that's exactly right. You add 12x15x0.1mm (or 0.2mm) shim washers between the shoulder just and the bearing to push the bevel gear forward. I put four 0.1mm shims in mine to remove the slop.

[Heli.Maniac]

How come I never had a problem with mine. My flying style is pretty hard with lots of tail-stressing maneuvers like piro tic tocs and I have never stripped a single set of the blacks which now are probably 300 flights old. Also running 2350 headspeed with 105s on the tail and 14 degrees of pitch.
What I did on my very first flight on these gears was to put some synthetic grease, run it and then clean up the excessive. That is probably why mine have held up so well.
Only time I have stripped gears in flight was once with the white ones that had worn out almost completely and second time with black gears that my stop gain was wayyyy too high. Guess I am very lucky until now.

Sent from my C6603 using Tapatalk

[mike d1]

Originally Posted by anmatheextreme

How come I never had a problem with mine. My flying style is pretty hard with lots of tail-stressing maneuvers like piro tic tocs and I have never stripped a single set of the blacks which now are probably 300 flights old. Also running 2350 headspeed with 105s on the tail and 14 degrees of pitch.
What I did on my very first flight on these gears was to put some synthetic grease, run it and then clean up the excessive. That is probably why mine have held up so well.
Only time I have stripped gears in flight was once with the white ones that had worn out almost completely and second time with black gears that my stop gain was wayyyy too high. Guess I am very lucky until now.

Sent from my C6603 using Tapatalk

I've had zero issues with my older 600 efl too. Sometimes it makes me wonder if they changed something in the manufacturing tolerances on the new 600 dfc's that has caused these stripping issues.

What motor are you running on yours?

The reason I ask is because I run the stock 600mx motor and maybe that's why I've had no issues. I do think sending the 750mx motor out with the newer kits is a mistake. Its a 700 class motor and IMO tis too much for the pro airframe without mods like going back to a belted tail. Belted tails provide a natural rubber buffer for the huge loads transferred on them. With a gear driven tail there is no buffer and the weakest part in the gear train will blow given to much stress via to much motor, to high gov gains, etc. I'm no heli designer, but I think its why you see belts on most of the larger helis over the torque tube design and why you see some having issues with stripped gears here.



Mike

[Heli.Maniac]

Also have the 600MX but on the other hand I am also stressing the tail with 105mm tail blades and high headspeed. I am thinking that Align stepped the quality of the parts further down or as you already mentioned, the 750mx is too much.
There are also guys that run way more pitch than is needed. On the 600mx, you can go up to 14degrees without issues but same pitch on the 750mx is going to stress parts.
How come people with the KDE motor (which is a powerhouse really) never had problems in the past?
I am so glad I got a belted 700 and that my only TT heli is my 600. Way more reliable and quiet and doesnt complain when I have my gains a touch higher or slightly touch the tail on a bad auto.

[mike d1]

Oh for sure if I was to buy something different I would go belted all the way. IMO the torque tube, like DFC, was bad hype, there just is no upside over a belt that I can see.

I bought my EFL cause I stole it, I paid a guy 500 bucks for a truly ready to fly heli. If my tail gears ever do start stripping swapping back to the old 600e tail belt is very easy, and quite honestly I don't know why more guys that are having problems with stripping don't make the switch??

Mike

[OnTheSnap]

Originally Posted by mike d1

Oh for sure if I was to buy something different I would go belted all the way. IMO the torque tube, like DFC, was bad hype, there just is no upside over a belt that I can see.

I bought my EFL cause I stole it, I paid a guy 500 bucks for a truly ready to fly heli. If my tail gears ever do start stripping swapping back to the old 600e tail belt is very easy, and quite honestly I don't know why more guys that are having problems with stripping don't make the switch??

Mike

I tried the belt and it was a major fail. Of course it depends on the pilot's style/skill. It's an ANCIENT belt design that dates back to pre-electric days. It's not strong enough to handle the demands of modern electrics in all out stick banging 3D. Now if your requirements are modest, it can work ok.

Another factor less discussed is tail setup. All systems are a little different, but if you can soften the tail stops as much as possible it really helps mitigate tail gear failures. Stops can be very stressful.

Also if you're hard on the machine, you need to proactively replace TT gears on any model between 50 and 100 flights. On my TT models I constantly check for wear and tend to replace them every 70 flights or so depending on the particular model. You can't go 200 flights flying hard, get a strip and then complain the gears are crap. These are wear items just like belts and require that you check and replace them often.

[mike d1]

Originally Posted by OnTheSnap

I tried the belt and it was a major fail. Of course it depends on the pilot's style/skill. It's an ANCIENT belt design that dates back to pre-electric days. It's not strong enough to handle the demands of modern electrics in all out stick banging 3D. Now if your requirements are modest, it can work ok.

Another factor less discussed is tail setup. All systems are a little different, but if you can soften the tail stops as much as possible it really helps mitigate tail gear failures. Stops can be very stressful.

Also if you're hard on the machine, you need to proactively replace TT gears on any model between 50 and 100 flights. On my TT models I constantly check for wear and tend to replace them every 70 flights or so depending on the particular model. You can't go 200 flights flying hard, get a strip and then complain the gears are crap. These are wear items just like belts and require that you check and replace them often.

Solid advice.

I had wondered about how tough the old belt design was. It was designed for 6s setups correct? Like I said before I have done nothing to mine. But I also have my gov and stop gains turned way down on the vbar and run the stock motor.

Mike

[Smoggie]

Originally Posted by mike d1

Oh for sure if I was to buy something different I would go belted all the way. IMO the torque tube, like DFC, was bad hype, there just is no upside over a belt that I can see.

The belt drive still uses the very same tail drive auto and transfer gears as the TT set up, and it's the transfer gear that often fails. Plus the belt drive gears are, as far as I know, only available in M0.6 material rather than the stronger M0.8 that the TT gears come in. So not safe to assume that putting a belt on will improve anything, it could make it worse!
Designs like Compass do away with the complexity of transfer gears and shafts altogether and simply run the belt off a pulley directly mounted to the main shaft.

Anyway, I've got a dozen flights or more on mine since stripping the gears on mine and it seems to be ok now, at least at the level I fly at.

[mike d1]

Originally Posted by Grumpy_Old_Man

The belt drive still uses the very same tail drive auto and transfer gears as the TT set up, and it's the transfer gear that often fails. Plus the belt drive gears are, as far as I know, only available in M0.6 material rather than the stronger M0.8 that the TT gears come in. So not safe to assume that putting a belt on will improve anything, it could make it worse!
Designs like Compass do away with the complexity of transfer gears and shafts altogether and simply run the belt off a pulley directly mounted to the main shaft.

Anyway, I've got a dozen flights or more on mine since stripping the gears on mine and it seems to be ok now, at least at the level I fly at.

There are people that have been using the belt successfully on the pro for a long time now. This is not my idea, its been on the forums longer then I have. Dont poo poo it unless you try it, didnt work for On the Snap, I myself have not tried it as my heli does not blow gears, but if it did I would try it.

Mike

[Smoggie]

I didnt 'poo poo' it, I just pointed out some facts regarding the 'weak link' components in the belt drive that are shared with the TT drive and said that it wasn't a safe assumption to think it would automatically improve the situation.

Seems like others in this thread have tried it and had problems, Some I'm sure have tried it without problem but there again many use the TT drive without problem too.

End of the day we are both discussing this with no experience of the belt drive on the trex 600.

[satgod]

Man this post is still going

2350 headspeed stock gears (I did replace the front TT gears with metal ones a little over a year ago just because of eveyone complaining about stripping the stock ones)
and to this day i've never had my tail blow out
I do run a slightly larger tail blade, 97mm If I remember correctly
+/- 14 degrees pitch and its rock solid even in extreme punch outs

[OnTheSnap]

Originally Posted by satgod

Man this post is still going

2350 headspeed stock gears (I did replace the front TT gears with metal ones a little over a year ago just because of eveyone complaining about stripping the stock ones)
and to this day i've never had my tail blow out
I do run a slightly larger tail blade, 97mm If I remember correctly
+/- 14 degrees pitch and its rock solid even in extreme punch outs

Cool! FYI - Punch outs aren't a good test of tail hold. It just verifies pre-comp really.

What I do is really 2 maneuvers. The first for me is a full collective backwards inverted hurricane, and then dropping the tail at full speed so that the heli has to hold against the airflow at speed. The other is really aggressive sideways (nose in) loops. These give me a good idea of where the tail performance stands.

[satgod]

well let me rephrase this

when I do funnels, hurricanes, tic-tocs and inverted reverse flight it doesnt move unless I move it and my gears are still there.

i've heard people say in a punch out they have stripped gears and I will at some point in almost everyflight do at least 2 or 3 punch outs, this is why I said that.

but you are correct it does verify your pre-comp really well

[rc_corner]

At 2400 RPMs the there is significant tail delay against the torque with the 95mm tail blades.

With the 750MX and full negative pitch (-12 Degrees) with a full Right Pirouette against the torque, the Front Torque Tube and Crown gears destruct every time. Please view my video above, which demonstrations the gears giving out and crashing the helicopter. In two months, I have crashed and rebuilt this helicopter over a dozen times due to this problem. I have also spoken with Align USA numerous times and they are uninterested in trying to obtain a solution.

Only viable solution is to port the electronics to a new Air Frame such as:

http://www.mdhelicoptersusa.com/inde...product_id=306

Helicopter is once again completely rebuilt and in new condition, but I have learned my lesson and will not fly this terrible helicopter again. For those who have success with this helicopter, please make me an offer on the airframe.

[OnTheSnap]

What makes you think the grass is any greener with a md 600? The 700 had several strips during flights in Vegas FF. Not saying its chronic, but unless you have first hand data not sure why you recommend it as a cure?

There are super robust TT models like the E5s, or great belt options with 6hvu, Logo or Goblin.

[rc_corner]

Yes I agree that more data is necessary before switching to the MD6 but after the experience I have had with this 600 and the nonsupport from align I am certainly that anything would be an improvement.

[OnTheSnap]

Originally Posted by rc_corner

Yes I agree that more data is necessary before switching to the MD6 but after the experience I have had with this 600 and the nonsupport from align I am certainly that anything would be an improvement.

I wouldn't make that assumption. There are LOTS of worse nightmares out there waiting. Trust me on that one. (-:

[ReadyToCrash]

sorry for my stupid question. why specifically the md6? aren't plenty of options out there?

[rc_corner]

I assume they are like the MD7 with a large metal front torque tube gear and massive drive gears. They were also offering replacement gears if they strip in flight. Not sure if this is still the case.

[jmtyndall]

Figured this is a good place to ask. With all this talk of 105mm tails possibly hitting the mains, and 95s not being enough authority at 2200rpm, is 100mm the answer? Found these while shopping for 105s and being concerned about main/tail strikes
http://www.helidirect.com/sab-red-bl...gn-p-18661.hdx