700 DFC tail issue

[Lee2782]

Originally Posted by bladechopper

I did flew 4 more times with re rails for a total of 6 flights. Hum still gone. I can't see or listen to any vibes... knock on wood. I hope it's gone for good.

Sent from my SM-N900T using Tapatalk

What headspeed are you running?

[-=RAGE=-]

Originally Posted by bladechopper

I did flew 4 more times with re rails for a total of 6 flights. Hum still gone. I can't see or listen to any vibes... knock on wood. I hope it's gone for good.

Sent from my SM-N900T using Tapatalk

Nice to hear!

My 700/rails combo did at least 50+ flights. Never heard this noise again. Love the 700 like no other machine in my hangar.

[bladechopper]

Originally Posted by Lee2782

What headspeed are you running?

I'm doing 1800 2050 and 2250

[bladechopper]

Originally Posted by -=RAGE=-

Nice to hear!

My 700/rails combo did at least 50+ flights. Never heard this noise again. Love the 700 like no other machine in my hangar.

That's nice to hear then. It's a sweet machine. I'm still nervous when flying it. I'm afraid of this big heli. Hopefully that will change in a few more flights

[-=RAGE=-]

You'll get used to the machine, bladechopper.
After many years of heli flying there is (thank god) still a healthy respect to helis of all sizes. That's very important.

[bladechopper]

Hey rage. Thanks. That's true man. Since I'm not that experience pilot with lots of flights due to small free time I do have. I fly only sport. But the sound of the blades of the 700 still makes me feel scared man. But like you said I do respect the helps a lot. I don't do anything stupid and as soon as I see people coming close to the heli just to see it flying I do land pack my stuff and go home and I tell them I'm out of more batteries even though I do have 10 packs waiting to be flown. I don't want to have any issues injuring anybody since I know that will make feel very bad

[Txboy]

I've read a lot so correct me if I'm wrong but the tail buzz was fixed with the rail tail blades. I've just bought the new dominator top and maiden flight was yesterday. I had the buzz at idle 1 about 2000 rpm head speed.

[rando]

Not sure anyone would call it a fix, but you're right that Rails usually resolve the issue, if you have it. Some in this thread reported they had to try other measures as well.

[bladechopper]

The magic rails blades fixed mine at any rpm

[Excalibur3]

It was a surprise when I maidened my new 700ltop and it had a nasty tail hum at 2000,2150,2250 rpm. I put a set of rails and bam no hum. I'm alittle disappointed that Align still hasn't a dressed the issue and to be honest I feel they owe me a set of rails. After all the supercombo is supposed to have everything to fly except rx, lipos,and TX. It didn't say and you need another companies tail blades as well. ?????

Trex700Pro/Trex700LTop/X3/14sgh T$3D

[Txboy]

Well finally got my rails in the mail and that did the trick. No tail hum at any RPM. I have also had correspondence with one of Align's Sr Tech's and he said and I quote "the easiest solution is to try different tail blades". So they are aware of the issue just figured I'd share.

[bendisar]

yeah it's annoying that after so much time the 700 still has the tail hum issue, but even for the added 25-30$ that you pay for the rail tail blades,
it still is a bargain priced 700. that flies very well

[BladeScraper]

Does it still hum with the upgraded tail shaft?

[bendisar]

yep, if its a 700DFC or a later model (with the high tail drive ratio), and you are swinging heavy tail blades at 2000 rpm or above, there is a good chance that the tail will hum, the rail tail blades are light, and with them the tail doesn't hum.

[BladeScraper]

Is there a black gear set that has a lower ratio?

[dchekas]

Yes.

However, it is not a helical style gear, it's a MOD 1.0 straight cut.

You will need P/Ns HN7020BA and HN7043B.

This will lower the gear ratio to 4.33.

You will likey need 115mm Tail blades if you are flying very tail demanding 3D maneuvers with this configuration. For sport/light 3D, it will likely run just fine with 105mm tail blades.

[BladeScraper]

Will Rail 116mm tail blades fit with 700mm mains?

[Excalibur3]

Originally Posted by BladeScraper

Will Rail 116mm tail blades fit with 700mm mains?

No and to be honest it's not necessary the tail holds great as is.

Trex700Pro/Trex700LTop/X3/14sgh T$3D

[BladeScraper]

Originally Posted by Excalibur3

No and to be honest it's not necessary the tail holds great as is.

Trex700Pro/Trex700LTop/X3/14sgh T$3D

Well, I was wondering if I brought the RPM down with the lower ratio to reduce hum, then throw longer blades on... I guess not?

I think I will stick to the ~690mm range on my 700, it's more smack-able at least that's what I hear. I currently have Edge 693SE, will probably pick up a set of Rail 696 when I break them.


Sent from my Gaui X3 using Pulse LiPo

[Volumax]

Originally Posted by BladeScraper

Well, I was wondering if I brought the RPM down with the lower ratio to reduce hum, then throw longer blades on... I guess not?

I think I will stick to the ~690mm range on my 700, it's more smack-able at least that's what I hear. I currently have Edge 693SE, will probably pick up a set of Rail 696 when I break them.


Sent from my Gaui X3 using Pulse LiPo

Do you have a tail hum in your Assault 700?