A reamer is used to finish a previously formed hole to an exact diameter with a smooth finish. It is not used to
significantly enlarge a hole.
Appropriate stock removal for most reaming operations is 2%-3% of the finished hole diameter, e.g. a 1/2" diameter
reamed hole operation would normally remove .010" to .015" of material.
A left-hand spiral is useful for thru-hole applications as the flute design will push the chips ahead of the cut.
A right-hand spiral is best for a blind-hole as the flute design will evacuate the chips by pulling out of the hole.
Both RH and LH spiral flute reamers are useful for bridging interruptions in the hole, such as grooves, crossholes or keyways.
Straight-flute reamers are useful for short-chipping materials like cast iron, bronze, free-cutting brass.
Appropriate feeds and speeds are critical to achieving finished ream-hole dimensions. Always consult the reamer
manufacturer recommended speed/feed chart, or call the MSC Metalworking Tech Team for advice.