Correct assembly of main gear 3DX500

[John Heli]

Hi there,

I am just wondering what is the right way to assemble the main gear on my 3DX500:

- is the gear with the deepening upwards or downwards?
- are the screws inserted from the bottom or the top?
- and where to place the metal washer?

Right now I have it the way it was from the factory: deepening of the gear downwards, metal washer on top and screws inserted from the top. But it makes noises like "tack, tack" when running out and the engine gear is really far down to reach the main gear.

Thanks for any hints!

[ml]

Hi John

check it out

Page 6

[ml]

OOOPS SORRY

HERE: http://www.helifreak.com/showthread.php?t=51501

[John Heli]

Thanks. The Version in the instructions is similar to the version I have, but I have a big washer for all screws holding the main gear.

I have attatched a version I found in an instruction for the 3DX500. There you can see the big washer. There is a report about the HDX500 on www.trextuning.com where they assemble the main gear similar. Isn't this a better solution comming closer to the motor?

[Mikej]

Hi there,

I am just wondering what is the right way to assemble the main gear on my 3DX500:

- is the gear with the deepening upwards or downwards?
- are the screws inserted from the bottom or the top?
- and where to place the metal washer?

Right now I have it the way it was from the factory: deepening of the gear downwards, metal washer on top and screws inserted from the top. But it makes noises like "tack, tack" when running out and the engine gear is really far down to reach the main gear.

Thanks for any hints!

John,

Mine is set up this way ....

- is the gear with the deepening upwards or downwards?
The flat face is up the cut-out is down
- are the screws inserted from the bottom or the top?
From the top
- and where to place the metal washer?
I don't have the washer

The pinion is a long way down the motor shaft. I think that if you had the gear the other way up that it would hit the belt ??

I have about 40 flights on it like this with no problems.

Where did you find the 3DX manual ?

Cheers,
Mike.

[John Heli]

Hi Mike,

here (http://www.maxprohobby.com/Maxpro/ProductDetails.aspx?ID=310) you can find a file containing some pictures of the 3DX500 assembly. This is where I got the file above. I saw some assemblies with the cut-out facing up. I think it will not hit the belt.

Cheers,
John

[John Heli]

In the build report made by trextuning.com (http://www.trextuning.com/hdx500.php) you can see the way the gear was reassembled. And later in the report attatching the motor you can see the cut-out facing up.

[Mikej]

John,

I should have said - mine is the way that it came assembled from the factory.

Thanks for the link.

Cheers,
Mike

[John Heli]

I think it all came assembled like the way we have it besides mine has the big washer and yours not. Maybe I just try flipping the main gear and report the effects.

[Rototerrier]

After ordering and installing a Revco 19t pinion, i felt more comfortable having it sit higher up on the shaft so I flipped the main gear. I have about 1.5-2mm of clearance. It looks like it will hit, but it won't and can't.

So, everyone having any doubt, take it from me...it can go either way, I have run it both ways and am currently running flipped and haven't had any trouble. not a nick on the belt and, what I would consider, plenty of clearance.