TESA of Renens, Switzerland, was the manufacturer of Compac indicators as well as Bestest, Tesatast and Interapid indicators.
For replacement models, please check our model equivalent pages.
The following tables of Compac metric models are taken from an antiquated TESA catalog and is being preserved here for reference purposes.
Compac models are designed to permit a true reading when the angle between the stylus and the reference surface is 0° (ie., they are parallel).
Since the dial test indicator is used as a comparator, the angle can usually be set to remain at 0° for all comparisons. However, when the indicator is run through its range while attempting direct readings or for calibration, this angle will of necessity change, introducing the cosine error.
In the rare cases when measurement is required with the stylus at an angle other than 0° with respect to the reference surface the readings should be corrected. Refer to calibration instructions for details.
While Compac test indicators are accurate ± 1 graduation when used as a comparator, they have total allowable deviations over their entire range as follows:
Who would buy a Rolls Royce if repairs weren't possible? Not to worry, Compac spare parts are available, in stock, and with our experience since 1959, repairs can effectively be made on any of these Compac indicators.
Additionally, we have now printed a Compac repair manual. Warning! It isn't easy.
It is imperative that the correct length of contact point be used with dial test indicators. Test indicators rely on leverage ratios to amplify the readings. Changing the length of the contact point will alter the ratio and result in incorrect readings. The common problem of incremental errors (ie, the readings gradually get worse from one revolution to the next) is most likely due to the installation of the wrong length point.
Most manufacturers specify the proper point length in their catalogs. It is not always clear, however, how the over-all length of the point is measured.
Compac contact points should be measured from the center of the carbide ball to the far end of the threads.
Some end-users purposely install extra-long contact points because their application requires it. If the contact point is exactly twice the length, then the readings on the dial will be doubled. Most 0,002 mm Compac indicators can be fitted with a long point which will make the graduations read 0,004 mm
Most manufacturers make indicators designed for use with long contact points. Compac test indicators have the letter designation "L" as a component of their model numbers.
Contact points can have a variety of ball diameters typically ranging from 1 mm to 3 mm and are available in carbide or ruby (special order). It is highly recommended that contact points fitted with carbide balls be used, especially for 0,002 mm indicators. The size of the ball diameter has no effect on the indicator's accuracy.
To find the ordering number for contact points refer to our contact points list
Q: I am interested in your metric Compac 213G dial test indicator. Would you please answer these questions about it? Is the crystal (glass) made of mineral glass or plastic? Is the bezel made of metal or plastic? What country are parts made in and where did the final assembly take place?
For answers to many other questions, please refer to our new publications shown below.
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