Girodtast indicators are manufactured in Court, Switzerland by BG Instruments SA, a family-run business founded in 1987, with approximately 40 employees.

Girod (a French word, approximately pronounced "she-row") is distributed by Fred Fowler in the U.S> and offered in a number of big-house catalogs. In Switzerland these are also available under the name SISO-tast. It's a top-of-the-line indicator, still made in Switzerland, structurally similar to the older Test and Bestest indicator. The current models include long range indicators with multiple revolutions, and sturdier crown gears that will resist the bending or breaking of gear teeth.

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To see how Girodtast indicators compare with their other Swiss cousins, refer to our brand comparison page.

Here is a simple way to tell whether you have the old or new model Girodtast.

Your old models will have the same black bearings on both sides of the body. Your new models will have different bearings on either side.

Old models (pre-2008) contact points are held securely in place with a set screw which is inserted from the back end of the pivot. Swivel the point to the side by 90° and you will see it. A very small screwdriver is needed to loosen this set screw by a half turn. This allows you to unscrew the contact point.

The old models had M1.6 threads and these will not fit the new "GL" series. Please continue reading.

Many Girod contact points have a strange burr above the thread. You may find that you can't insert the new point without stoning off this burr. When the new point is screwed in, you'll want to tighten the set screw again. Notice that, if the set screw is too far out, you may not be able to swivel the pivot back into position.

The same set screw is used to shorten or lengthen the contact point so that the indicator calibrates correctly. It's quite a nuisance. You'll have to calibrate the indicator and if the readings are over by one graduation or more, you 'll want to lengthen the point. Do this by screwing it out, by 1/2 turn at a time, and then retightening it before checking calibration again. Repeat until you get it right.

Why did the manufacturer torment us with this "feature"? If the contact point is used at an angle,, you will have to made mathematical adjustments for the cosine error. However, on this dial of indicator you can permanently adjust the length of the point so that readings at particular angles will always s be correct. If you have made such an adjustment, be sure to label the indicator so that you will remember next time. For example: "reads accurately at 30 degrees"

New models (since 2008) of the "series GT" have eliminated this setscrew, making adjustments and mathematical calculations unnecessary. They now operate on the same principle as the Brown & Sharpe Bestest indicators. New model contact points have M1.4 threads and will not fit the older models.

How can you tell whether is it M1.4 or M1.6? Just take your old point and measure it metrically with a calipers or a micrometer. M1.4 threads will measure 1.4 mm in diameter.