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    11 Products

    Economy Small-Bore Gauge Sets

    Image of ProductInUse. Front orientation. Contains Inset. Bore Gauges. Economy Small-Bore Gauge Sets.
    Measure the diameter of small holes, grooves, and recesses. These gauges help you find deviations in size or roundness that can cause precision parts, such as engine or valve cylinders, to wear quickly or run poorly. They have a full-ball probe, which has a 360° contact surface that’s easy to center in tight spaces. Compared to gauges with an anvil, spring-loaded contact, or half-ball probe, they’re less likely to tilt inside a bore and skew measurements.
    Insert the probe into a bore and turn the knob on the handle to expand the contacts. Measure the distance across the contacts with a micrometer to find the bore diameter.
    Distance Measured
    Range
    Material
    No. of
    Gauges
    Includes
    Each
    Full-Ball Small Bore
    0.125" to 0.5"Steel4One full-ball gauge with 0.125"-0.200" measuring range and 61/64" max. depth
    One full-ball gauge with 0.200"-0.300" measuring range and 1 3/64" max. depth
    One full-ball gauge with 0.300"-0.400" measuring range and 1 5/32" max. depth
    One full-ball gauge with 0.400"-0.500" measuring range and 1 19/64" max. depth    		6741A47000000
     

    Starrett Small-Bore Gauges

    Image of Product. Full-Ball Gauge. Front orientation. Contains Inset. Bore Gauges. Starrett Small-Bore Gauges, Full-Ball.

    Full-Ball

    Gauge

    Image of Product. Half-Ball Gauge. Front orientation. Contains Inset. Bore Gauges. Starrett Small-Bore Gauges, Half-Ball.

    Half-Ball

    Gauge

    Measure the diameter of small holes, grooves, and recesses. The end of these gauges has a 360° contact surface that’s easier to center in tight spaces than anvils or spring-loaded contacts. Use them to measure slots and bores in precision parts, such as electronics, where small size deviations can cause inefficiencies.
    Insert the probe into a bore and turn the knob on the handle to expand the contacts. To find the bore diameter, use a micrometer to measure the distance across the contacts.
    Full-Ball—Full-ball gauges are best for deep bores. They’re less likely than half-ball gauges to tilt within the bore, which helps to avoid skewed measurements caused by placing the gauge off-center.
    Half-Ball—Half-ball gauges are best for measuring near the bottom of flat, shallow bores.
    Distance Measured
    Range
    Max. Dp.
    Measured
    Material
    Mfr. Model
    No.
    Each
    Full-Ball Small Bore
    0.125" to 0.2"2 1/2"Steel829A2100A1000000
    0.2" to 0.3"2 1/2"Steel829B2100A200000
    0.3" to 0.4"2.7"Steel829C2100A300000
    0.4" to 0.5"3"Steel829D2100A400000
     
    Half-Ball Small Bore
    0.125" to 0.2"2"Steel831A2205A100000
    0.2" to 0.3"3"Steel831B2205A200000
    0.3" to 0.4"3"Steel831C2205A300000
    0.4" to 0.5"3"Steel831D2205A400000
     

    Starrett Small-Bore Gauge Sets

    Image of Product. Full-Ball Gauge Set. Front orientation. Contains Inset. Bore Gauges. Starrett Small-Bore Gauge Sets, Full-Ball.
    Image of Product. Half-Ball Gauge Set. Front orientation. Contains Inset. Bore Gauges. Starrett Small-Bore Gauge Sets, Half-Ball.

    Full-Ball Gauge Set

    Half-Ball Gauge Set

    Check a variety of hole, groove, and slot diameters. Each gauge in these sets has a different measuring range. The end of these gauges has a 360° contact surface that’s easier to center in tight spaces than anvils or spring-loaded contacts. Use them to measure slots and bores in precision parts, such as electronics, where small size deviations can cause inefficiencies.
    Insert the probe into a bore and turn the knob on the handle to expand the contacts. To find the bore diameter, use a micrometer to measure the distance across the contacts.
    Full-Ball—Full-ball gauges are best for deep bores. They’re less likely than half-ball gauges to tilt within the bore, which helps to avoid skewed measurements caused by placing the gauge off-center.
    Half-Ball—Half-ball gauges are best for measuring near the bottom of flat, shallow bores.
    Distance Measured
    Range
    Material
    No. of
    Gauges
    Includes
    Mfr. Model
    No.
    Each
    Full-Ball Small Bore
    0.125" to 0.5"Steel4One full-ball gauge with 0.125"-0.200" measuring range and 2 1/2" max. depth
    One full-ball gauge with 0.200"-0.300" measuring range and 2 1/2" max. depth
    One full-ball gauge with 0.300"-0.400" measuring range and 2.7" max. depth
    One full-ball gauge with 0.400"-0.500" measuring range and 3" max. depth    		S829EZ2100A50000000
     
    Half-Ball Small Bore
    0.125" to 0.5"Steel4One half-ball gauge with 0.125"-0.200" measuring range and 2" max. depth
    One half-ball gauge with 0.200"-0.300" measuring range and 3" max. depth
    One half-ball gauge with 0.300"-0.400" measuring range and 3" max. depth
    One half-ball gauge with 0.400"-0.500" measuring range and 3" max. depth    		S831EZ2205A5000000
     
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