James,
How much material in hanging out of the chuck? You should chuck the material up close, with a minimum sticking out.
Is you tail stock in line with your spindle?
118 deg should be just fine for drilling.
A 120 degree spot drill would be best. A center bit (drill) is not really made to start hole, it's made to center the work on a center.(hence the name)
To reduce chatter, increase feed rate or reduce surface speed or increase rigidity. or all three.
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(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management) |