making gears?

[daniel_leavitt2000]

I have very specific gear that I need an experiment. It needs to have 10 teeth, have  diameter of 4.75mm and should mesh with gears from Minitrix. I can not find any online. Does anyone have any ideas?

[mmagliaro]

I assume the outer diameter is 4.75mm.

module x (numTeeth + 2) = outer diam

So it is a mod .395, and that means, I bet, that it really is a module 0.4 gear and that outer diameter
is really 4.80mm. 

An 0.4 module 10 tooth gear is not hard to find. 
An eBay search for  10t 0.4 mod pinion
hit two of them.

What bore do you need for the center hole?

This place has them:
http://www.pojezdy.eu/eshop/107-spur-gears-m04
I've ordered from them.  Got my stuff.  They seem reliable from a quick scan of some R/C car forums.

These guys have spur gears that are 0.4 mod, 10T,
http://www.gizmoszone.com

Northwest Shortline has them as well.   

A general web search of "0.4 mod 10t" will find a lot of sources.  Luckily, 0.4 mod gears are cheap and easy to
find and make.

[mmagliaro]

One more really good source, which I have also ordered from with success:
http://shop.kkpmo.com/product_info.php?info=p604_gearwheel-pinion-m0-4---10teeth.html

You'll see at that link that you can get an 0.4 mod 10 tooth gear with almost any bore from 0.8mm to 2.0mm
any width from 1 to 8mm, in black or white acetal or brass.