What module/pitch are the Gaui Pinions?

[Zoobie]

I want to buy a smaller pinion for my 1100 Kv, but I was wondering what module/pitch the pinions are?

I see the revco ones are 0.6 module and the Quick ones are 32 pitch which is 0.793 module, is this a problem. I am a little nervous about abusing the Guai gears after all the problems they had.

thanks.

[hommer75]

A little search could have told you that you can calculate the Module of a gear with the equation: OD/(z+2). Here the OD is the Outer Diameter of the gear in mm and z is the number of teeth on the gear.
The 14T gear I have here has an outer diameter of 12.5mm, diveded by 14+2 gives a Module of 0.78.

[Zoobie]

Sorry, but I dont really understand the theory of modules / pitch. Are you saying that it varies depending on the number of teeth? I see it is a ratio, but I dont really want to make a mistake here.

That also does not answer then why readyheli are selling 0.6 module pinions as upgrade? How critical is the module?

thanks.

[hommer75]

The module is a ratio of teeth vs. gear diameter; the 14T gear is 12.5mm filling that in the equation: 12.5/(14+2) = 0.78 module.
I also have a 42T Gaui gear here which has a diameter of 35.4mm => 35.4/(42+2) = 0.8 module.
Reversing that; a 0.6 module 14T gear will have an outer diameter of: OD/(14+2) = 0.6 => OD = 0.6*(14+2) = 9.6mm

So comparing two 14T gears, a 0.6 vs a 0.8 module gear. The 0.8 gear is larger than the 0.6 module gear. So to acomplish a bigger diameter with the same amount of teeth the gap between the teeth and the theeth themselfs on the 0.8 module gear will have to be bigger then on the 0.6 module gear.

Basically, mixing 0.8 and 0.6 module gears is a bad idea since the teeth will not mesh correctly and you get touble transferring power which may even result in the gears failing (loosing teeth).

Hope that clears it up.

[Zoobie]

Thanks for that. Now that I understand how it works I can make educated choices.