How to Use a Dial Bore Gauge for Bore Size and Roundness
Zero the gauge against a micrometer or setting ring, then rock it in the bore to find the true minimum reading.
A small measuring mistake can reject a good part or release a bad one. Start with How to Use a Dial Bore Gauge for Bore Size and Roundness, then check zero, contact point, hand force, and reading method before deciding whether the part passes.
What to Check
- a dial bore gauge is useful for checking bore size, roundness, and taper
- it must be zeroed against an outside micrometer or setting ring before the real measurement
- inside the bore, rock the gauge to find the minimum reading instead of holding it still and guessing
How to Apply It on the Shop Floor
On the shop floor, measure with a fixed sequence. Do not pick up the tool and trust the first number. Clean, zero, choose the correct feature from the drawing, then repeat the reading. If the value moves too much, find the cause before averaging it away.
Important Cautions
This article is a practical use and checking guide. It does not replace your work instruction, calibration procedure, or quality system. For tight tolerances or critical customers, compare against a master and follow the required calibration schedule.