Pulley Specification

Hello,

I'm buying my pulleys rather than making them using the printed parts.
First off, is this a good idea?

I need to know the specifications of the x, y, and, z pulley. So far I know the x and y have the same Outer Diameter (20 mm?), but have different internal diameters (6 and 8mm respectively?).

Can someone please list the specifications.
Also, any suggestions on what kind to be, and what things to look out for?

Sorry if this is a really common question. But, your comments will be MUCH appreciated.

Thanks,
UTRA

5mm internal I think for X and Y - whatever matches your motors. remember, Z motor needs a pulley too, so 3 with 5mm ID and 2 with 8mm ID. The pitch is 5mm, and remember to get a belt with a tooth profile that's ok with tight radii

hello,
i need to know about all the details of pully design. A, B, C, types, effective diameter, etc.. and also how to select a pully according to my requirment (gear ratio, max/min dia, motor shaft dia.. etc)
pls let me know ASAP
regards

sahan