Trying to make a gear pump

[Futterama]

Okay then. Lots of views but no replies.

I have changed tactics. I'm going to get a gear cutter and cut my own gear so the axle and gear is made from one piece. I have a few questions regarding gear pumps and I'll see if someone here can answer.

How does the following parameters affect the pump characteristics?

1. Number of gear teeth.
2. Gear width.
3. Teeth size (e.g. module 1 vs. module 2).

My idea of the parameters above are:

1. Low number of teeth: Low flow, high pressure. High number of teeth: Higher flow, lower pressure due to the increased load on the motor driving the pump.

2. Narrow gears: Low flow. Wide gears: Higher flow, increased motor load.

3. Small teeth: Low flow, high speed motor. Bigger teeth: Higher flow, lower speed motor.

The gear pumps I have seen around the internet, always have few teeth, around 10, which is AFAIK the smallest gear in the module system, and the gear width is somewhere around the same as the gear diameter.
Any particular reason for this?

If I was to make a hydraulic gear motor, would bigger gears be an advantage to get more torque or does the bigger gears have a negative impact on performance due to the changed angle at which the gears mesh?