Tech Tip #108 - Reamer Hand of Cut and Flute Selections
Reamer flute choices vary from straight flutes to flutes with a right-hand spiral (RHS) or left-hand spiral (LHS) orientation. In general, they are all right-hand cut (RHC) regardless of flute spiral direction.
Consider these guidelines for when straight, RHS, or LHS flutes are appropriate.
- Straight-fluted RHC reamers are for general-purpose use in a wide range of materials. They are best used for through holes less than 2x diameter deep.
- RHS/RHC reamers are used for blind holes or deep holes because they carry cut chips out of the hole. They are free cutting and normally produce a better finish. RHS reamers are particularly well suited for cutting aluminum alloys, copper, and other free-cutting non-ferrous material.
- LHS/RHC reamers are an advantage in through holes because they push chips ahead of the tool. They are most often used in steels and irons. They consume more torque to operate, but can reduce chatter in less than ideal setups.