This is a good question. I don't know of anyone who has come up with a methodolgy to calculate machinability yet. I am sure there have been attempts. I would certainly also like to see one.
One problem is that machineability is a response variable that has not been clearly defined. What...
Daewoo makes a very rigid machine for a decent price. Their vertical machine centers come standard with box ways, direct drive spindle and coolant through the spindle. I am not sure of the price for a 50 taper machine, but I know you can get a new 40 taper machine for around $80,000 base price.
I agree that your groove width is a function of your cutting tool. I recommend that you go with a +.002/-.000 slot width. Milling cutters and end mills tend to cut over their nominal size due to runout. Furthermore, according to the Machinery's Handbook, standard keyway tolerances are...
