True Precision Corporation
Indianapolis, IN  USA

Exclusive Manufacturer of :
Multi-Ball Thread Gage Logo

Multi-Ball Micrometer
Internal Thread Micrometer

The Multi-Ball internal thread micrometer is a new instrument for measuring the size of an internal thread.  It is very small and light weight making it easy to use even where space limitations restrict the use of other instruments. It is completely self contained so that the purchase dial indicators and other accessories is not necessary. It never requires any set-up or assembly so it is always ready for immediate use.

The Multi-Ball micrometer patented design utilizes 3 balls as contact elements.  By turning the friction thimble the balls are rolled into contact with the work piece.  Since they are free floating they will never develop flats or wear unevenly.  Unlike other types of gages the Multi-Ball micrometer contact elements can be positioned anywhere along the thread. The most common locations are at 180 and 120.  Calibration is performed in a matter of seconds by adjusting the calibration sleeve on the micrometer to correspond with the size of a solid setting-ring.

Multi-Ball Location Gage
Internal Thread Location Gage

The Multi-Ball internal thread location gage is a new type of gage used to measure the location and orientation of an internal thread axis.  It works by aligning itself with the theoretical pitch cylinder axis of the screw thread.  When in position the Multi-Ball gage provides a precision cylindrical surface that can be accurately measured by coordinate measuring machines (CMM), dial indicators, and other inspection equipment.

Unlike other types of location gages the Multi-Ball location gage is mechanically engaged.  It has 2 patterns of 3 balls spaced 120 apart located at each end of the threaded portion of the sleeve.  After positioning the gage in the threaded hole, the pin is turned causing the balls to roll into contact with the work piece thread flanks.  The pin centers itself inside the pattern of 6 balls aligning the pin axis with the thread pitch cylinder axis.  The balls in the Multi-Ball gage are the only parts that contact the work piece thread flanks.  This makes the Multi-Ball gage totally independent of all work piece features except for the pitch cylinder axis.  Accurate location and orientation of the thread axis can be determined even when the adjacent part surfaces are not square with the thread.  The gage is easily removed without any resistance by turning the pin counterclockwise.

See the Frequently Asked Questions page for more information.


        Telephone: 317-899-0899
                   Fax: 317-899-5374

Postal Address: True Precision Corporation
                            831 South Post Road
                            Indianapolis, IN  46239

Electronic mail: General Information/Sales:  

Copyright 2001-2004 True Precision Corporation ALL RIGHTS RESERVED
Last modified: November 09, 2004

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