stripped Main gear?

[Foxden]

Originally Posted by Down Low

Are the 90 gears injection molded or machined ?
DL

Injection Molded

[statton1]

so wuts causing the gear stripping? i ask cause now after getting my muffler bolt prob fixed i now have a gear missing 2 teeth ,it happened as i was spooling up ...i heard a chattering sound then i saw the gear stop and then slowly start moving,but i killed the throttle. now im staring at it and can't figure it out

[RotaryBliss]

its appearing to be mildly common.. cause still unknown, The weather hasent cooperated well enough to try out the spares I have now..

[statton1]

i think im gonna just leave this one alone 4 a lil bit ,gear mesh was good flew four 9min flights yesterday without a hitch........................yeah rite ill be swapping gears in a lil bit,but still any ideas why 2 teeth would jump of the gear ?

[statton1]

i cant figure it out ,i kinda dont wanna finish fixing it not knowing wut went wrong .

ive had so many test hops ,full power climb outs ,pitch pumping and to have it strip just b4 taking off ,when i had flown it just b4 this happened............hmmmmmmmm

does it need zero backlash? i compared it to my v50 and the v50 has the sam amount .hm m.... i really dont want to start messing with frame holes........................................

[olafluna]

me too i have around 14 fligths and a ready change 4 main gear the fisrt 8 fligths the first main gear because is mising 2 teeth also de second one i just start the heli and the hole gear got broke so i change it i fluw 4 more fligths and again other main gear i am 2d pilot i dont know whats is te problem and the final gear i fluw the heli i make a half flip and i losse power me heli is crashed i have to better main gears

.monsterdog
atte

[olafluna]

here are the pics will no fligth this machine if i dont get better main gears its not me firts heli but yes the firts one whit this issue


atte:monsterdog

[raptorheli2]

i spoke with charley today about this-i hope he doesn't mind me saying but they know about this and charley is fixing it now as he is at the factory taking care of all the issues people have found.....good to see someone/company that cares.

cheers

[statton1]

that is why i like outrage - and that is why i didnt freak out when it happened .

[kazager]

I'm wondering if it isn't so much a tooth issue as it is a gear flex/support issue. "MOST" of the missing teeth I see are right at the edge of the "open web" for lack of a better description. Maybe it just needs to be more fully supported. Just something I noticed. Since I don't have one, just keeping up on the news here...Is there a set direction of the gear, or can it go in either way?

[RotaryBliss]

its not a set direction. I would attribute it to brittle materials if I were to guess..perhaps just a slight modification on the chemestry, heat, what have you to increase the gears modulus of elasticity. I boiled the gear in water I have in mine now for 4 minutes.. I pounded on it pretty hard this weekend and all seems to be just peachy so far after 5 flights.. compass had an issue with brittle landing gear and this seemed to help somewhat so I thought what the heck Id give it a try.. time will tell..

[statton1]

now that u mention it ,i do remember after flight #6 seeing a wobble in the main gear,which prompted me to switch out the main shaft yes i ignored a sign

[statton1]

are these the fix 4 some of the problem with main gear -i bought new shafts at helidirect ?

[TheDuck]

Yep stripped mine today after doing some fast tic tics.. 3 rd hard flight on the heli....ys3ds was hungry.......
So far..... Stripped gear and broken a few tail guides

[statton1]

has comprado nuevos ejes principales, tal vez podría ayudar a-también intentar doblar la Guía de cola trasero-i tuvo buen vuelo hoy con la mina fue capaz de tratar de dientes inactivos por fuera y no rotos-también ese gy 701 fácil de configurar mañana va a activar la parte de gov del giróscopo.


sorry i meant

have you bought new main shafts ,maybe it might help- also try doubling up the rear tail guide-i had good flight today with mine was able to try idle up out and no broken teeth -also that gy 701 easy to set up tomorrow i will activate the gov part of the gyro.

4got i had translator on -

[statton1]

this is with gy 701 just gyro is active-(gov sensor will be installed later )new main shaft and main gear

[biglahou]

Sorry everyone Ive been out and not involved lately, but this problem with the main gear has had me looking real hard as the reason for it.

I am schooled in the trade I'm in that studies secondary damage and this main gear is based on secondary issues that are not related to a bad main gear.

If you all look at your lower main shaft bolt hole you will see that your main shaft and the 4 mm bolt their is to much play, this bolt should almost twist into the main shaft like it does to the lower drive gear and sleeve as to eliminate back lash.

Now a heli doing heavy ticktock's and load and unload the main shaft it acts like an air hammer on the main gear to pinion gear.

You don't see an immediate breakage of a main gear till after flying it for some time so the teeth are getting worn down to fast from this play from the lower main shaft to 4mm bolt.
Ive talked to many about this and Charley is aware of the issue and Im sure he will let us know what will be done.

As for the fix for now I put green loctite between lower portion of main shaft to one way sleeve, installed main shaft and while pushing up on main shaft forcing the bolt to ride on lower most portion of hole on main shaft and while pushing up I installed a collar on top of top bearing block to hole shaft into place which now utilizes upper bearing block.
I still get -11 deg pitch with blade without hitting collar and that is good for me right now till the fix is finished.
Last I tighten up the lower bolt as tight as possible, and so far not teeth for me have broken.

[DominicD]

I would love to see the mounting method at the bottom changed to the way it is done at the top, the jesus bolt and 2 side bolts.

[tS8103]

My new main shafts came in yesterday. The hole at the bottom was a perfect fit with very minimal slop. I installed it today and it has no vetical play. i will take to to the field tommorrow and beat on it and see if it hold. BTW these new shafts have only the one hole at the bottom drilled to the proper size.
Tone

[Foxden]

Thanks Tone for the update