Main Gear Mesh

[Greg Jackson]

I have the helicopter finished almost.  Just have to get the esc and bec soldered and then center the servos and put the wheels on and servo arms.  But one issue I'm having.
I don't feel the main gear mesh is how it should be.  I even put in moly Kote and its just a little tight I think. I will not maiden until someone looks at it but is there anything I can do to fix it? I tire the paper, tried Chris' way in the video, just not happening.

[RichL]

I have the helicopter finished almost.  Just have to get the esc and bec soldered and then center the servos and put the wheels on and servo arms.  But one issue I'm having.
I don't feel the main gear mesh is how it should be.  I even put in moly Kote and its just a little tight I think. I will not maiden until someone looks at it but is there anything I can do to fix it? I tire the paper, tried Chris' way in the video, just not happening.

First, does the gear mesh feel tight or does the main shaft feel tight.  Back the motor and pinion away from the main gear and give the main shaft a spin.  A little tightness is expected in the beginning but, if it is overly tight them you may have to lightly sand the delrin shim that sits on top of the auto hub.  Next, how many shims did you add between the Jesus bolt collar and the lower bearing block?   Another potential cause could be that you have over tightened the one or both bolts that go through the lower part of the main shaft.  These bolts require no torque at all on the nut. Over tightening the nut will cause gear mesh problems as well as tightness in the main shaft.  If the main shaft feels ok then, either of the previously described methods of setting the gear mesh should work.  When setting up the gear mesh you want to find the tightest spot between the main gear and pinion and do your mesh adjustment from there.  This may mean the another area on the gear mesh seems a little loose, this is also normal.  A very small amount of gear lash is desirable.

Rich 

[Greg Jackson]

Before I put the motor in I checked the mesh between main gear Nd front transmission.  Very smooth even before I applied the moly Kote.  After I put in the motor I kept checking, ran the piece if paper through and tons of stuff.  I can spin it, it's not "un-spinnable" but it just seems tight.  Put some scorpion motor on the motor also.