RunRyder RC
WATCH
 1 page 1989 views POST REPLY
Home✈️Aircraft🚁Helicoptere-Elec-Helicopters New or Limited ActivityAvant › Avant Aurora maiden that could have been total loss
12-28-2014 06:23 PM  5 years ago
Topic Vote0Post 1
AgentOrange

rrVeteran

Jacksonville, Florida

MyPosts All Forum Topic
Avant Aurora maiden that could have been total loss
Well today was the day that I was going to maiden my Avant for the first time after about two months of total tear down and rebuild. A little history of it I got it used and when I got it she was in pieces. So I loaded the manuel and started cleaning and building. The build went kinda smooth as this heli is a lot harder to build and labor involved then any other helis I have had. Well after about three weeks I pur together the main gear assembly. I thought the use of a pressure pin instead of a bolt and nut was a little odd but thats is what it called for. Now on to the maiden that was going ok as I needed to tune the motor a little and fine tune the flight controls in the air. I did a few circuts and brought it back checking different things as I put in the air agian and started to do more circuts and piros to check my piro rate I heard a slight clicking noise. As I started to bring the heli back it got louder. I landed it by me and when I brought the collective to full down the tail stopped spinning the main gear stopped spinning but the head continued to spin. I shut the motor off and looked it over and found that the main gear pin that connects to the main gear and main shaft was almost completely fallen out. If that had happened in flight it would have been a total loss and a very sad day for me. I am now going to put a bolt and nut in there so this does not happen again. Have any of you Avant Aurora 90 nitro owners had this happen to you.
Trying not to put them in the dirt.
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-28-2014 07:15 PM  5 years ago
Ladymagic

rrKey Veteran

South Korea

MyPosts All Forum Topic
Oh wow, that was a close call. Glad you caught it in time.

I can't say that I've had that happen to me, but I know that was one of main the things I thought about when I was building the Aurora.

Frankly, I don't like that concept at all. It really adds no benificial value to the design and makes removing the main shaft a real pain after the heli is built. It also has a higher potential to fail if the set screw comes loose like what happened to you. Personally I think it was one of those things that was designed just for the sake of being different where a jesus bolt works just fine.

But, like I said, I was worried about it when I put it together so I used a little extra loctite on the big set screw and I used a little blue loctite on the pin itself.
Mellisa
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-28-2014 07:32 PM  5 years ago
TMoore

rrMaster

Cookeville, TN

MyPosts All Forum Topic
Did the pin have a flat ground on it for the setscrew to lock up?Part 107.
The only ZERO flight hour certificate in the world.
It's like getting a driver's license without the driver's test.
SHARE  PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
12-28-2014 08:00 PM  5 years ago
AgentOrange

rrVeteran

Jacksonville, Florida

MyPosts All Forum Topic
No with the Avants its a pin with no set screw.Trying not to put them in the dirt.
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-28-2014 08:16 PM  5 years ago
dkshema

rrMaster

Cedar Rapids, IA

MyPosts All Forum Topic
Copy of assembly manual page from the Avant Aurora Ultimate 90:

It seems to go to very great lengths to make sure you not only install the pin, but suggests red or blue loctite AS WELL as the M6 set screw that installs into the bottom of the mainshaft, to hold the pin in place.

Seems to be the same thing on the e-Aurora...

-----
Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-28-2014 08:22 PM  5 years ago
AgentOrange

rrVeteran

Jacksonville, Florida

MyPosts All Forum Topic
Well hell I guess I missed that during the build. Dont I look like an dummy.lol. Well I guess I saved my self from my own stupidity. Thanks for that.Trying not to put them in the dirt.
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-28-2014 08:25 PM  5 years ago
dkshema

rrMaster

Cedar Rapids, IA

MyPosts All Forum Topic
Perhaps you used up one of your Christmas miracles. Happy to hear that a missing 10 cent part didn't cost you hundreds of dollars in repairs!-----
Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-28-2014 08:33 PM  5 years ago
Einzelganger

rrKey Veteran

Campbell, Texas

MyPosts All Forum Topic
Concept looks good, just like a tail rotor shaft.
I would rather see a Jesus bolt though.
That really will be a pain to disassemble.

Glad you caught it in time!

Wayne
I love the smell of nitro in the morning.
RIP Roman
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-28-2014 08:48 PM  5 years ago
Blax1

rrVeteran

Sydney Australia

MyPosts All Forum Topic
Been there done all of that, AgentOrange use a bolt and nyloc nut!
Because the main shaft is hollow, this allows the grub screw to actually bend the pin, regardless of tension and using the ground flat method (which probably weakens the pin anyway) in time fatigue sets in, the pin cracks, then centrifugal force takes over and the pin parts company, it's a down hill slide from there on, mine did exactly the same at three feet off the deck in a hover, then drilled itself it the ground because the main shaft pulled up about 3/4" thus applying God only knows how much negative pitch!
One side frame, a skid and a set of mains went south that day!
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-28-2014 09:09 PM  5 years ago
AgentOrange

rrVeteran

Jacksonville, Florida

MyPosts All Forum Topic
Ya I was just out looking at and it looks impossible to remove the main gear and pin if heli is fully assembled. So like some of you had suggested I installed a bolt and nut and have applied a liberal amount of lock tight and am ready to try and get if off the ground again.Trying not to put them in the dirt.
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-29-2014 03:02 AM  5 years ago
Clarence Creer

rrVeteran

Fort Worth, Texas

MyPosts All Forum Topic
It is not impossible. You need to use an L shaped Allen Wrench.Team Kontronik Team minicopter/PeakAircraft
VTeam EvoPowerBattery
SHARE  PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
12-29-2014 01:25 PM  5 years ago
icanfly

rrElite Veteran

ontario

MyPosts All Forum Topic
interesting way to secure a pin rather than having a bolt and nylock nut. You want to remember how much upward force the shaft is exerting while in the air doing 3d, the jerking up and down on the pin would be shortening the life of it compared to a bolt where side pressure is clamping the sides of the main shaft slightly. The pin might have been an idea used to prevent distortion of that part of the gear and owb. Personally I would substitute the pin for a bolt AND use the little set screw to add that little bit of extra security while not wrenching the bolt very hard.

good luck
btw, I made my own retaining bolt out of metal rod I threaded on either end to the very outside of my main gear and used a nylock nut on each side, for the heli in the avatar.

We haven't heard much about Avant lately, I like the product line.
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-29-2014 02:14 PM  5 years ago
rudyy

rrElite Veteran

E. Amherst, NY

MyPosts All Forum Topic
I am surprised to see the pin to be used in this application. The M4 shoulder head screw/jesus bolt is a lot more secure.
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-29-2014 05:03 PM  5 years ago
dkshema

rrMaster

Cedar Rapids, IA

MyPosts All Forum Topic
A bolt and nut here do little with respect to "clamping" anything. Try picking up an eight pound cylinder by pinching it between your thumb and forefinger. Also try to accelerate/decelerate it (spin) using the same approach.

A hardened steel pin will easily take the rotational load from the power train as well as the G loads from flying around. Improperly tightened, the bolt/nut combo can interfere with proper operation of the autorotation bits and pieces by deforming the cylindrical parts.

A small flat ground on the pin for the set screw and the proper application of torque and thread locker should be more than sufficient here.
-----
Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-29-2014 05:56 PM  5 years ago
tonyd12

rrApprentice

hamlin,PA

MyPosts All Forum Topic
pin
That was a common occurance with my raptor 60/90.
SHARE  PM  EMAIL  Attn:RR  Quote
12-29-2014 10:01 PM  5 years ago
RappyTappy

rrProfessor

Encinitas, CA

MyPosts All Forum Topic
If you use a bolt and nut instead of the pin, make sure you are using a shanked/shouldered bolt where that the shoulder at least goes all the way through the main shaft and most of the auto hub. Just using a regular all threaded bolt can break under loads because the threads are not designed for side loads like that and that can cause a crash as well. I like the designs that use a hardened rolled pin and on each side a set screw holds it in place, MA and Century had that design that I can remember, very secure and those pins are ridiculously strong.Still buyin' and flyin' then crashing and cryin'
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
12-30-2014 02:02 AM  5 years ago
HeimD

rrVeteran

the great southwest

MyPosts All Forum Topic
Learn how to auto and things like that don't have to be a "total loss".
SHARE  PM  EMAIL  Attn:RR  Quote
12-30-2014 02:33 AM  5 years ago
RappyTappy

rrProfessor

Encinitas, CA

MyPosts All Forum Topic
Gonna be hard to auto a loss of that lower pin/bolt when the entire rotorhead with main shaft depart company with the airframe, lol. Saw it happen to a Raptor once at the field, head goes flying off like a top and airframe becomes a plummiting lawn dart. Sickening and fun to watch all at the same time, lol.Still buyin' and flyin' then crashing and cryin'
SHARE  PM  EMAIL  GALLERY  Attn:RR  Quote
WATCH
 1 page 1989 views POST REPLY
Home✈️Aircraft🚁Helicoptere-Elec-Helicopters New or Limited ActivityAvant › Avant Aurora maiden that could have been total loss
 Print TOPIC  Make Suggestion 

 9  Topic Subscribe

Sunday, April 5 - 1:46 am - Copyright © 2000-2020 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online