What can cause reamers to cut oversize due to built-up edges?

What can cause reamers to cut oversize due to built-up edges?

• A. Too minimal stock allowance
• B. Excessive stock allowance
• C. Incorrect reamer size
• D. Low-speed operation

Answer: (B)

Reamers can cut oversize partly due to built-up edges when there is an excessive stock allowance. When the stock allowance is too high, the reamer is forced to remove more material than it is designed to handle in a single pass. This can lead to overheating, which causes the material to adhere to the cutting edge of the reamer, creating a built-up edge. These edges disrupt the cutting action, causing the reamer to cut oversized holes rather than achieving the precise dimensions intended. In contrast, having minimal stock allowance would typically encourage a tighter tolerance and reduce the chances of built-up edges because the reamer would only need to remove a small amount of material, minimizing heat generation and the possibility of material adhesion. Wrong reamer sizes might lead to inaccuracies but not directly cause built-up edges. Low-speed operation can slow down the process but does not inherently lead to oversized cuts due to built-up edges as effectively as having too much material to remove.

Reamers can cut oversize partly due to built-up edges when there is an excessive stock allowance. When the stock allowance is too high, the reamer is forced to remove more material than it is designed to handle in a single pass. This can lead to overheating, which causes the material to adhere to the cutting edge of the reamer, creating a built-up edge. These edges disrupt the cutting action, causing the reamer to cut oversized holes rather than achieving the precise dimensions intended.

In contrast, having minimal stock allowance would typically encourage a tighter tolerance and reduce the chances of built-up edges because the reamer would only need to remove a small amount of material, minimizing heat generation and the possibility of material adhesion. Wrong reamer sizes might lead to inaccuracies but not directly cause built-up edges. Low-speed operation can slow down the process but does not inherently lead to oversized cuts due to built-up edges as effectively as having too much material to remove.