1. Check the condition of the Boring tool to be sure it is not damaged or worn.
2. Be sure the correct Boring Bar is mounted and called up by the Program.
3. Check that the correct Tool Offsets are entered and active.
4. If all other features bored by this tool have the same dimensional problem, adjust the Length offset as required.
4. Be sure the Boring Bar is securely mounted in the Tool Holder.
5. If other features bored by this tool are correct, adjust the Z axis coordinate for the hole, if allowed by shop practice.