In Gage Threadcheck's Official Blog

Go to Threadcheck

New Thread Check Catalog

Thread Check Inc., is proud to announce the release of our 2016 Precision Gage Solutions catalog with over 180 pages of precision gages, measuring instruments and technical information. Our new catalog is available for download or in an electronic book format for easy use. The new catalog has links to where our customers can shop on line, request quotes and view hundreds of technical articles. Use the table of contents to quickly turn to the product selection of your choice. Use electronic book marks for the pages you visit frequently. The new electronic catalog works across all platforms including tables and smart phones.

Thread Check Catalog 2016 Cover




Alternate Size Thread Measuring Wires

It is possible to use standard 60 degree thread measuring wires to calibrate 55 degree British thread plug gages and external product. Thread Check often receives inquiries for special thread measuring wires to calibrate Whitworth/British 55 degree threads. Although Thread Check Inc. can certainly supply these special thread measuring wires, the cost is higher and the lead time to manufacture is typically 4 weeks or more. The best solution is to select a standard 60 degree thread measuring wire which is close to the 55 degree thread measuring wire diameter and simply adjust the constant value. This alternative set of thread measuring wires with an adjusted constant for the 55 degree thread angle will achieve the same exact results. The same method can be applied to 29 degree Acme and 45/7 degree buttress threads.

All “Best Size” thread measuring wires have a maximum and minimum wire diameter that may be used to measure pitch diameter. Maximum and minimum thread measuring wires should be used which are safely within the limiting dimensions given by the formulas below.


Include Thread Angle Max. Best Min.
60° 1.010362p .57735p .505182p
55° .82573p .563692p .50568p
29° Acme .650013p .51645p .487263p

P=pitch  n=TPI   P=1/n

The wide range of standard wire diameters in stock found within the 60 degree inch and metric sizes and the 29 degree acme sizes makes it possible to find a wire diameter very close to a required British or special size. The measurement of pitch diameter is least effected by an error in the included angle of the thread by a wire diameter which is closest to the calculated best size wire.

Related topics regarding thread measuring wires:

Thread Check’s expert sales engineers can assist our customers with selecting the correct wire size and calculating the new constant value to ensure accurate measurements.

Thread Check Inc
900 Marconi Ave
Ronkonkoma, New York 11779
Tel: 800 767 7633



Gear Measuring Wires

Thread Check's gear measuring wires are used to check the tooth thickness of gears at the pitch diameter. The gear wire method is more accurate than using tooth verniers to measure the tooth thickness. A measurement over the wires using a micrometer is compared with a perfect gear which is obtainable from the Van Keuren Handbook No 37. The Van Keuren Gear Measurement Tables are accurate to .0001" for 1 diametral pitch gears. A value based on the selection of pressure angle, number of teeth, and wire size is divided by the diametral pitch of the gear being measured. If the actual measurement is larger than the table value then the teeth are thick. If the value is smaller then the teeth are considered thin. A copy of the Van Keuren Handbook can be purchased on line at

Thread Check's gear measuring wires are supplied in sets of 2 identical wires. Thread Check's gear measuring wires meet or exceed Federal Specification GGG-W-366B for Grade AMGW. Wires are lapped  to RMS micro inch finish or less. Contact Thread Check Inc for modified gear wires, carbide gear wires, flatted gear wires.
Thread Check offers Gear measuring holders for both 2 and 3 wire gear applications. Please provide measuring instrument and spindle diameter when ordering.