Dimensional tolerance of drilling holes on iron and
Normal drilling machines can meet the
diameter tolerance of 0.1 to 0.2mm, after reaming, the tolerance
could be met to 0.05mm. As for higher tolerance of 0.01 to 0.02mm,
the digital controlled drillers will be needed.
There is no big difference for dimensional tolerance of drilling
holes on cast iron and cast steel parts, but steel castings can
reach higher surface finish quality.