Hi team,
I will be making a shaft around 6mm diameter and around 130mm long. To keep the weight down I'm thinking of drilling out the centre but as we all know drills can wander off line. I can attempt to minimise this with a good quality drill, a good headstock~tailstock alignment, good collets and with lots of pecks.
With say a 3 or 4mm drill, how deep do you think I could sensibly go ? I'm not worried about the strength of the shaft, a little about eccentricity but more drill breakage.
Gerry