http://www.youtube.com/watch?v=xxl5G14uUv8 This happend today
The heli was new counting about 22 flights
I cant understand the reason the main shaft pin gone away ( or broke ?)
The resault is a bad damage of the heli , BUT the frame is undamaged!!
That shows the quality of the heli...
when i was going to find it i was thinking that probably nothing left undamaged
is it a good idea to replace the pin with a Socket head cap screw with a Nylon insert Locknut ?
I don't know for sure why your mainshaft pin would come out, but a possibility is that you didn't tighten the main shaft set screw enough. As a hint for the rebuild, when installing the pin again, put blue locktite on the pin before inserting. Just spread it around the pin and insert it. This will ensure that in the event your set screw is not tight enough or it loosens, the locktite will hold the pin in.If you want to use solely a screw and lock nut, you need to drill out the mainshaft and auto hub to 4mm.Thomas.Thomas Moore Team Avant Team Edge
Ive seen this happen twice to the team pilots, once they realized the manual called for loctite on the pin itself, they have had many flights afterwards with no issues what so ever. You need to not only loctite the set screw that holds the pin in, but the pin its self.AMain.com Mikado "V Team" Xnova Motors Optipower USA RCProPlus
Aaaaauuuutchhhhh. I feel sorry for you man.I have tried to break the pin once after an Auto.
Luckily it was the last one, so I discovered when carrying it back to the table.I think you overtightened the set screw and the pin broke in the end (Maybe after some of your hard autos )Avant recommends NOT to use anything but the original pin????Good luck with the rebuild - It doesn't look that bad.
- But a shame with that nice canopy.
the truth is that i didnt use loctite directly to the pin but only to the screw that holds the pin...
But i didnt overtight the screw because i took the main shaft out before a couple of days to clean the main shaft oneway and i saw the pin it was ok.
anyway i will loctite everythink this time.
Also i want to say that this was the 1st time that the rotor was running at 1950 rpm at idle up 2 (i usualy fly at 1850 rpm idle up 1)As for the canopy its the last think that i m worried about because i paint them
Thank you very much for your advices
i d like to ask somethink
is there any posibility that the pin broke when i canceled some autos
with governor on so full power was imediatelly?
could this brake the pin?
I was going to mention the autos - doing power recovery autos with a 90 is a bit risky. The engines have so much power it is a lot of stress on the sprague bearing, especially on the Aurora which has had so many issues with the sprague slipping.John Benario
I use to grind a flat spot on the middle of the pin to have the screw engage. That way loctite on the screw is enough and also ensures that you only need to snug the screw w/o stressing the pin. Loctite on that pin can make it a real pain to get it back out in cases of maintenance Used that method on all pins used in that heli.Dan
ouch..always happens at the worst times huh?I understand Daniel about it being a pain to remove but if this was me I would take all possible measures to ensure it doesnt happen again..includeing drilling and tapping for more setscrews
I posted the video to Avant forums trying to get some answers from the pro but they didnt allow the post and untill now no answer...
Very good customer service!!!
and i m wondering why they didnt allow the post?
I totally understand where you are coming from. Glad you cam get an answer from both forums.Here is an excerpt from the manual stating that the pin needs to have locktite applied on the pin itself before installation.Thomas Moore Team Avant Team Edge