How does someone go about doing this, what gets justified as a tight tolerance and a loose tolerance.
If per say you had 3 different parts 1/3/12" ID hole to be turned in a 24" long part 1.5" wall thickness with the following unilateral ID cylindrocity and ID dimensional tolerance for the sake of discussion lets say these parts are 4140 @ 80 ksi heat treat or 6061 T6
0.0001
0.0005
0.001
0.005
0.010
My experience says that the 0.0001 is very difficult to achieve on 4140 I would have the part roughed, heat treated and final ground to size, even then the cylindrocity would be very difficult without a knowledgable grind shop.
I am not asking for pricing, but is there some sort of rules of thumb, or is this all experience based?
If per say you had 3 different parts 1/3/12" ID hole to be turned in a 24" long part 1.5" wall thickness with the following unilateral ID cylindrocity and ID dimensional tolerance for the sake of discussion lets say these parts are 4140 @ 80 ksi heat treat or 6061 T6
0.0001
0.0005
0.001
0.005
0.010
My experience says that the 0.0001 is very difficult to achieve on 4140 I would have the part roughed, heat treated and final ground to size, even then the cylindrocity would be very difficult without a knowledgable grind shop.
I am not asking for pricing, but is there some sort of rules of thumb, or is this all experience based?