Small Hole Gages
These small hole gages are well balanced tools that are ideal for accurately measuring small holes, slots, grooves, and recesses in all kinds of work. They all feature:
Hardened-ball measuring surface with two-point contact
Radius on each gage is less than the minimum diameter to be measured, which provides the two-point contact necessary for maximum accuracy
Smooth, sensitive adjustment for better feel, giving more accurate measurements
The adjustment of the gage beyond their range is restricted by a safety stop that prevents breakage
Accurate measurements are obtained by slightly “rocking” these gages in the hole to be measured. This will guarantee contact at the true diameter. The final size is then
obtained by measuring over the ball contacts with a micrometer.
These gages are exactly the same as the No. 831 Series except that all gages are
only 2 (50mm) long, making them convenient to use in close quarters.
Part Number S830FX