Spur gear selection for parallel shafts

[novato]

Hi,

I have a DC motor with 4mm diameter shaft, flat tip.

How can I attach a 12 teeth pinion to this drive shaft?. I have been loking for pinions and gears on the web but they don't specify how are they attached to a shaft, as there are round shafts and flat tip shafts. Do I have to ask for gears with hub and set screw?

Any help would be very appreciated.

Novato

 

[Mech_Engineer]

There are many ways to do it, one of the simplest would be a set screw in the gear's hub, like on this W.M.Berg gear:

http://www.wmberg.com/catalog/photos/B05B065.jpg
http://www.wmberg.com/catalog/productsearch.aspx?url=http://wmberg.smartcats.com/sc_app/default.asp

 

[novato]

The set screw is a good option but, is there any stainless steel gear that matches a flat tip shaft like this?

 

[FredGarvin]

Your question doesn't make a whole lot of sense. The flat is made for the set screw. Who/what are stanley steel gears?

 

[novato]

Your question doesn't make a whole lot of sense. The flat is made for the set screw. Who/what are stanley steel gears?

Thank you. I have seen some gears that have an opposite shape for flat tip shafts.
PD: I'm sorry about the bad spelling.