understanding datasheets

[darkloaf]

Hey,

I am just about to start cad-ing my robot, and I'm having some troubles understanding my motors datasheet.
http://www.active-robots.com/products/motorsandwheels/stepper-motors/datasheets/103h546-0440.pdf

What unit are these measurements in? For example the motor bore is listed as ø5-0.013. What the devil does that mean?

Cheers,

Nick Deboar

[Ro-Bot-X]

The units are milimetres. ø5-0.013 means the diameter is 5 milimetres and the -0.013 is the tollerance of machining, so the axle is 13 micrometres less of the nominal value, so it will mount with little effort to a ø5 gear.

[darkloaf]

Great, cheers!