I didn't machine the shafts because of the level of accuracy that they needed to be; I was busy making other components of the robot/transmision.
Everything on our robot is built in Tunkhannock High School by students with the help of mentors.
The only thing we had to "outsource" for these transmissions from the school was the shafts and gears to get heat-treated, since our school does not have this capability.
They were made in the school and then taken to some company for the heat treating.
Shifting Question:
Our transmission really does not take that much strength to change gears. The main thing they need to shift is accuracy. We used two small pneumatic cylinders to shift.
On cylinder moved the transmissions to either first gear or third gear; the other cylinder was used to wedge the shifting forks into second gear. This required the cylinder that shifts the gears from first to third to become pressureless.
Here is the best pic I can find at the moment:
http://www.tigertrons.com/2004/2004bot3.JPG
Also more pictures can be found here:
http://www.tigertrons.com/pictures.htm