700 DFC tail issue

[Coolice]

Originally Posted by blackout19

The top of the pinion (when viewed as fitted) is where the teeth start, and at first they are shallow, and get deeper as they move down the pinion untill they reach max depth for the rest of the pinion. With the original main gear it wasn't as thick, so didn't reach up far enough to come into contact with the start of the pinion teeth.

The new one is thicker, and now this is a possibility.

Hey buddy.

This pinion isn't the 700E one as the one we use has a turned step on top of the teeth that rests against the motor support bearing.
.

[Chris Wall]

Well, I just ended up leaving the white gears on both ends of the torque tube and using the new black ones until I get extra bearings in... With only one set of bearings I do not want to damage them while pressing on - hopefully it will be fine to fly this weekend like that...

[Coolice]

Here's a photo of my pinion to maingear

[Dino Spadaccini]

No good raise the pinion so its level with the bottom of the main gear that why its tight

[Dino Spadaccini]

i would not do white and black mix as the black is a harder material and you may brake of wear out the white in no time just my thoughts

Dino

[Chris Wall]

Originally Posted by Dino Spadaccini

i would not do white and black mix as the black is a harder material and you may brake of wear out the white in no time just my thoughts

Dino

Thanks for the information Dino, just out of curiosity, how in the heck did you get the umbrella gears on? I bent my PrecisionHeliTools.com mini press trying to get the bearings on! I certainly do not want to deform the bearings or the umbrella gear... I'll take any suggestions, I left the gears in the freezer over night!

[blackout19]

Originally Posted by Coolice

Hey buddy.

This pinion isn't the 700E one as the one we use has a turned step on top of the teeth that rests against the motor support bearing.
.

Changed the image in my original post to the correct one. The point still stands though, you don't want the main gear meshing where the teeth start at the motor end of the pinion.

[stevehof]

If you have to raise the pinion off the motor shaft support bearing in order to ensure the pinion to main gear mesh is correct, aren't you defeating part of the purpose of the motor shaft support bearing? That is, to keep the pinion from 'pulling' down on the motor shaft due to the helical gears. That, of course is very hard on the motor bearings.

[Chris Wall]

Originally Posted by cwall64

Thanks for the information Dino, just out of curiosity, how in the heck did you get the umbrella gears on? I bent my PrecisionHeliTools.com mini press trying to get the bearings on! I certainly do not want to deform the bearings or the umbrella gear... I'll take any suggestions, I left the gears in the freezer over night!

Success - freezer / oven & brute force!

[Dino Spadaccini]

the supports the shaft not the pinion gear, if you feel your bearing i bet its very rough from the gear riding on it and align has posted on there FB to do it this way Dino

[Dino Spadaccini]

http://www.facebook.com/photo.php?fb...type=1&theater

http://www.facebook.com/photo.php?fb...type=1&theater

[rando]

...

[jimmitch]

Is there a new Helical Autorotation Tail Drive Gear to go with the black gears? Mixing the two can't be good.

[Steemo]

Originally Posted by jimmitch

Is there a new Helical Autorotation Tail Drive Gear to go with the black gears? Mixing the two can't be good.

It'd certainly look more uniform too.
I have the black main gear and the white auto gear under it just doesn't look right.
That being said I think you would strip the black umbrella gear before the white auto gear would go. I could be wrong.

[rcflyerheli]

Originally Posted by rando

To Dino's point, it's always been the case that the pinion is NOT supposed to rest on the shaft support bearing.

I think what they're saying is new is that due to the new main gear being slightly thicker, you need to line the pinion and gear up at the bottom edge to make sure it's not meshing with the beveled portion of the pinion. With the original gear, there was an extra mm to play with for vertical alignment.

My manual (V2 version, not DFC V3), page 17 shows an inset drawing with specific instructions to make sure the pinion is in contact with the bearing prior to tightening the grub screws. Is there some change notice that I missed?

[stevehof]

Originally Posted by rcflyerheli

My manual (V2 version, not DFC V3), page 17 shows an inset drawing with specific instructions to make sure the pinion is in contact with the bearing prior to tightening the grub screws. Is there some change notice that I missed?

With my Synergy E7 you are supposed to have pinion just touching the bearing. The reason given is that due to the helical cut gears there is downward pressure on the pinion. If the pinion is free to pull down, that is hard on the motor bearings.

My understanding of the pinion support bearing (when used with helical gears) is that it serves two purposes. One is to keep the motor shaft rigid and remove the possibility of the motor/pinion flexing away from the main gear. Two, is to keep the pinon from pulling down on the motor shaft.

Seems to me Align has probably fixed the gear stripping with the thicker better composition gear but now the setup really needs a new longer pinion so it can be mounted touching the bearing as was the original spec.

[rando]

Originally Posted by rcflyerheli

My manual (V2 version, not DFC V3), page 17 shows an inset drawing with specific instructions to make sure the pinion is in contact with the bearing prior to tightening the grub screws. Is there some change notice that I missed?

I thought the manual said exactly the opposite but maybe it's something I read in the forums somewhere. In any case, I'll retract my comment and updated my original post.

[rcflyerheli]

Originally Posted by rando

I thought the manual said exactly the opposite but maybe it's something I read in the forums somewhere. In any case, I'll retract my comment and updated my original post.

That's why I went back and looked at the manual, as it's been over a year since I built my 700. I haven't looked at the V3 DFC manual to see what it says, maybe it's different.

Nope, I just looked at the DFC manual, and on page 15 it says exactly the same thing.

[Dino Spadaccini]

do not let the pinion gear touch the bearing

[msallua]

Thanks AlignTrexStore,com