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Optical Comparators

Optical comparators also referred to as optical projectors or contour projectors project the shadow of the work piece onto a glass screen.  They offer the capability to measure difficult and special configurations.

The optical comparator is typically used with a chart overlay that has detailed cross hairs so that the movement of the part can be measured from one edge to another. Other overlays offer radius lines and thread angles.

Many optical comparators are equipped with a range of magnifying lenses so that images can be projected at 10 to 50 or more times the size of the original object.

The optical comparator plays a vital role in quality inspection.


Optical Comparators


Gagemaker Ball Pitch Diameter Gages

Thread Check offers a wide range of pitch diameter gages manufactured by Gagemaker. These types of gages are commonly known as ball PD gages as they accurately measure pitch diameter which is one of the most important characteristics of a thread. Pitch diameter represent the widest spectrum of potential defects on a screw thread. Improperly sizes pitch diameters compromise the load capacity of your threaded components.

Gagemaker uses contact point (or contact ball) gages to inspect lead, taper, height, and pitch diameter on nearly any type of thread. Generally, these gages require two contact
points. Our points are inter-changeable; one set of points often can be used on different types of inspection gages. For best results, we still recommend one set of points for each gage.
Gagemaker offers spherical points and truncated points to measure pitch diameters. Truncated points as illustrated ensure contact on the flanks of the thread pitch line and eliminate the possibility of bottoming out on the root or minor diameter of the thread.

truncated points are used to measure pitch diameters of certain straight threads, primarily Acme, Stub Acme, and the modified Stub Acme threads.

Spherical points are commonly used for *UN Series, Metric, 7x45 Buttress, and nearly all tapered threads (tubing & casing and rotary shouldered connections).

Note: Remember when setting a gage with truncated points set on the truncated surface of the point. Gagemaker will provide set-to-flat value to compensate for the truncation.

Gagemaker Ball Pitch Diameter Gages

Gagemaker Ball Pitch Diameter GagesGagemaker Thread Gages


Accurately Inspecting Rotary Shouldered Connections without plug and ring gages

Gagemaker’s new Joint Strength System – JSS is fast, versatile and effective at certifying RSC connections. The JSS System allows the inspector to measure and have greater control over all the attributes that affect performance of the connection.

This gauging system will inspect any API thread and verify the accuracy to API specification tolerances.

Inspecting Rotary Shouldered ConnectionsInspecting Rotary Shouldered ConnectionsInspecting Rotary Shouldered Connections without plug and ring gagesInspecting Rotary Shouldered Connections without plug and ring gages


Functional Size Thread Inspection

Functional size thread inspection is fast, easy to use, affordable, and versatile for inspecting threads. The Gagemaker PG-6000 and RG-7000 functional gages use two precision ground thread rolls that seat into the thread form and contact the thread at the pitch line. The gages are zeroed at a preset calculated thread size. Deviations from nominal size are read on the indicator. Thread rolls are able to determine variations in form, lead, taper, and height all simultaneously just as the thread plug and ring gages do. The PG-6000 and RG-7000 are set using gage blocks, micrometers, or Gagemaker’s MIC TRAC measurement center. Thread ring and setplug masters are not required.

The PG-6000 Series gages inspect diameters of internal threads. The RG-7000 Series gages measure diameters of external threads.

Common pitches ranging from 4 TPI to 20 TPI of the UN Series, ACME, and Stub ACME, and 1.5mm to 4 mm of the ISO Metric thread rolls are in stock. Whitworth and 7° X 45° Buttress thread rolls are available with short lead time.

With the PG-6000 and RG-7000, thread diameters up to 24 inches can be easily and accurately measured.

Functional Size Thread InspectionFunctional Size Thread InspectionThread Inspection

Thread Inspection