Large Fasteners & Formed Components
Concentricity and runout inspection of larger fasteners, cold-formed specials, and cylindrical hardware within the B-40 size range.
Universal Punch Concentricity Gaging System · Model B-40
B-40 Concentricity Gage
Precision concentricity and runout inspection for larger cylindrical parts.
3/4–4 in (20–102 mm) diameter · Up to 8 in (203 mm) part length
3/4–4 in
Part diameter
Up to 8 in
Part length
14.5 in
Gage length
B-40 Concentricity Gage
Precision runout inspection for larger cylindrical parts.
The Universal Punch B-40 is the large-capacity B-series concentricity gage for roller-supported rotational inspection of cylindrical components. The workpiece is supported on precision rollers and rotated while an indicator monitors variation at the selected measurement location for concentricity and runout inspection.
The B-40 is specified for parts from 3/4 in to 4 in (20–102 mm) in diameter and up to 8 in (203 mm) long. Universal Punch has more than 30 years of experience with its Concentricity Gaging System, including model selection, roller options, indicators, accessories, application engineering, and calibration support.
When to choose B-40
Choose the B-40 when your part requires up to 4 in of diameter capacity or up to 8 in of
part length. If the part also fits a smaller model, Universal Punch can review the support
surfaces, roller geometry, and indicator access to determine the best configuration.
01
Larger Part Capacity
3/4–4 in diameter
Up to 8 in part length
Up to 8 in part length
02
Controlled Part Rotation
Manual timing-belt drive
Smooth inspection cycle
Smooth inspection cycle
03
Adjustable Indicator Positioning
Fine carrier positioning
Multiple measurement locations
Multiple measurement locations
04
Application Engineering
Roller-family selection
Configure from the actual print
Configure from the actual print
B-40 Technical Specifications
B-40 capacity and physical dimensions.
These specifications define the standard B-40 size range and gage dimensions. Final application fit also depends on the part's support surfaces, roller selection, indicator access, measurement location, and inspection objective.
Part Diameter
3/4–4 in
20–102 mm
Part Length
Up to 8 in
203 mm
Gage Length
14.5 in
368 mm
Gage Width
6 in
152 mm
Shipping Weight
11.2 lb
5.1 kg
How the B-40 Concentricity Gage Works
Support the part. Position the indicator. Rotate smoothly. Read variation.
The B-40 combines precision roller support, an adjustable top-arm yoke, fine indicator positioning, and smooth manual rotation so a quality technician can inspect radial variation through a controlled, repeatable setup.
01
Precision Roller Support
Roller geometry supports the part at the surfaces selected for inspection.
02
Adjustable Top-Arm Yoke
Stabilizes the workpiece during rotation while preserving indicator access.
03
Indicator Carrier
Fine adjustment positions and zeros the indicator probe at the inspection feature.
04
Timing-Belt Drive
Provides smooth manual part rotation while indicator variation is observed.
01
Precision Roller Support
Configure support around the part.
02
Adjustable Top-Arm Yoke
Stabilize the workpiece.
03
Indicator Carrier
Position the probe precisely.
04
Timing-Belt Drive
Rotate the part smoothly.
01
Precision Roller Support
The part is supported on the roller geometry selected for its diameter, support surfaces, and required measurement access.
02
Adjustable Top-Arm Yoke
The multi-position top-arm yoke stabilizes the workpiece during rotation while preserving access to the feature being inspected.
03
Fine-Adjustment Indicator Carrier
The carrier positions the indicator probe at the required measurement location and provides fine adjustment for setup and zeroing.
04
Manual Timing-Belt Drive
The standard timing-belt pulley system provides smooth, controlled manual rotation so indicator variation can be observed through the inspection cycle.
B-40 Application Engineering
Configure the gage around your part—not the other way around.
Send Universal Punch the part print and inspection requirement. Application engineering can review the part size, support surfaces, feature being inspected, datum relationship, roller geometry, indicator access, and carrier position to help configure the B-40 for the job.
01
Part Size & Support Surfaces
Provide the part diameter, overall length, and the cylindrical surfaces available to support the component on the rollers.
02
Feature Being Inspected
Identify the diameter or feature being checked, its datum relationship, and where the indicator probe must contact the part.
03
Roller Configuration
Match Full Plain, Half Plain, Quarter Plain, or special main rollers to the support land, adjacent shoulders, and required clearance.
04
Indicator & Carrier Position
Confirm the indicator type, probe access, measurement location, and carrier position needed for the inspection workflow.
B-40 Main Roller Options
Choose the roller geometry that supports the part correctly.
Universal Punch offers 140-size Full Plain, Half Plain, and Quarter Plain main rollers for the B-40, plus special main rollers made to order. Roller selection determines where the part is supported, the clearance available around adjacent features, and access to the measurement location.
140FP
Full Plain Rollers
Full-width plain roller support for cylindrical surfaces when broad support contact is appropriate.
140HP
Half Plain Rollers
Reduced-width roller support that can provide additional clearance near shoulders or adjacent part features.
140QP
Quarter Plain Rollers
Narrower roller support for applications requiring localized contact or additional measurement access.
SPECIAL
Special Main Rollers
Made-to-order roller geometry for parts that cannot be properly supported with a standard main-roller configuration.
Not sure which roller style fits the application? Send the part print. Universal Punch can review
support lands, shoulders, interrupted surfaces, required clearance, and indicator location before the roller configuration is specified.
B-40 Concentricity & Runout Applications
Built for repeatable inspection of larger cylindrical components.
The B-40 is used where a larger cylindrical part must be supported on rollers, rotated smoothly, and checked with an indicator for concentricity or runout-related variation. Common users include quality departments, inspection labs, toolrooms, and production teams.
Machined Shafts & Sleeves
Rotational inspection of turned shafts, sleeves, and other machined cylindrical components where radial variation must be evaluated.
Ground Cylindrical Components
Inspection of ground diameters using controlled rotation and indicator contact at the required measurement location.
Incoming Quality Inspection
Evaluate supplier parts and incoming lots with a repeatable roller-supported rotational inspection setup.
In-Process & Final Inspection
Support setup verification, in-process checks, final inspection, and quality documentation workflows.
Custom Inspection Setups
Configure roller support, indicator access, and carrier position around the actual part print and inspection requirement.
B-40 Service & Replacement Parts
Designed for long-term service and support.
The B-40 is built from identifiable mechanical assemblies and service components. Universal Punch can use the gage model, assembly identifiers, and application details to support replacement-part, service, and configuration requests.
B-20 vs. B-40 Concentricity Gages
B-20 or B-40? Start with part diameter and length.
The B-20 is specified for parts from 3/8 in to 2 in in diameter and up to 6 in long. The B-40 covers 3/4 in to 4 in in diameter and up to 8 in long. If a part fits both models, support geometry, indicator access, and the preferred inspection setup should also be considered.
Medium-diameter B-series
B-20
3/8–2 in
Diameter
Up to 6 in
Part length
Large-diameter B-series
B-40
3/4–4 in
Diameter
Up to 8 in
Part length
Model-selection guidance: choose B-40 when the part exceeds the B-20's 2 in diameter or 6 in length capacity. For parts within the overlap between the two models, Universal Punch can review the print and recommend the more appropriate support and inspection configuration.
B-40 FAQ
B-40 selection, setup, and application questions.
These answers cover the questions engineers, quality teams, and buyers most often need resolved before selecting a B-40. For a final configuration, send Universal Punch the part print and inspection requirement.
What is the B-40 Concentricity Gage used for?
The Universal Punch B-40 is a roller-supported rotational inspection gage for larger cylindrical parts. The part is supported and rotated while an indicator monitors variation at the selected measurement location for concentricity and runout inspection.
What size parts can the B-40 inspect?
The B-40 is specified for parts from 3/4 in to 4 in (20 mm to 102 mm) in diameter and part lengths up to 8 in (203 mm).
What are the B-40 gage dimensions?
The B-40 has a published gage length of 14.5 in (368 mm), a gage width of 6 in (152 mm), and a shipping weight of 11.2 lb (5.1 kg).
How does the B-40 Concentricity Gage work?
The workpiece is supported on precision rollers, stabilized by the adjustable top-arm yoke, and rotated with the manual timing-belt drive. The fine-adjustment indicator carrier positions the probe at the inspection feature so variation can be observed during rotation.
What is the difference between the B-20 and B-40?
The B-20 is specified for 3/8 in to 2 in diameter parts up to 6 in long. The B-40 increases the range to 3/4 in to 4 in diameter and up to 8 in long. When a part fits both models, roller support, feature access, and the preferred inspection setup should also be considered.
What main roller options are available for the B-40?
The B-40 uses Universal Punch 140-size main-roller families, including 140FP Full Plain, 140HP Half Plain, and 140QP Quarter Plain rollers. Special main rollers can also be supplied for application-specific support requirements.
How do I know which B-40 roller configuration I need?
Send Universal Punch the part print with the diameter, length, support surfaces, feature being inspected, datum relationship, and indicator location. Application engineering can review the part and help determine the appropriate roller and indicator configuration.
B-40 Application Review
Send your part print. Universal Punch will help configure the B-40.
Include the part diameter, overall length, support surfaces, feature being inspected, datum relationship, measurement location, and any tolerance or reporting requirement. Universal Punch can review model fit, roller geometry, indicator access, and carrier position before the B-40 configuration is quoted.