When finishing a hole by reaming, how much material should remain?

When finishing a hole by reaming, how much material should remain?

• A. 0.001-0.005 in
• B. 0.005-0.010 in
• C. 0.010-0.020 in
• D. 0.020-0.030 in

Answer: (B)

Finishing a hole by reaming relies on the reamer removing only a small amount of material to bring the hole to its final size while improving roundness and surface finish. Leave about 0.005–0.010 in of stock in the hole after drilling so the reamer has enough material to cut cleanly without rubbing. If you leave less than about 0.005 in, cutting may be inconsistent and the surface finish can be rough due to rubbing. If you leave more than about 0.010 in, the reamer would have to remove more material, which can increase cycle time and risk deflection or loss of concentricity. So, the best practice is to leave 0.005–0.010 in of stock for the finishing pass.

Finishing a hole by reaming relies on the reamer removing only a small amount of material to bring the hole to its final size while improving roundness and surface finish. Leave about 0.005–0.010 in of stock in the hole after drilling so the reamer has enough material to cut cleanly without rubbing. If you leave less than about 0.005 in, cutting may be inconsistent and the surface finish can be rough due to rubbing. If you leave more than about 0.010 in, the reamer would have to remove more material, which can increase cycle time and risk deflection or loss of concentricity. So, the best practice is to leave 0.005–0.010 in of stock for the finishing pass.