Tape Measure Calibration Procedure

You will not be able to fix a tape measure that was not accurate to begin with. For this reason we recommend using a Lixer to check accuracy before purchasing a new tape measure. Lixer Tools now offers tape measures which have been carefully selected using the following procedures. We have found different brands have their own range of accuracy and precision. We have tested many brands and sizes. When I have purchased tape measures using a Lixer, I typically reject 5 out of 6 tape measures that I check. 

No matter which brand of tape measure we have tested, we find that accurate end hook placement is a challenge to the manufactures. The end hook movement is also inconsistent from tape measure to tape measure. A new tape measure should be checked for accuracy before you buy it. We have seen many new tape measures that were off by more than 1/32”. A few tape measures have been off more than 1/16”. The manufactures original placement of the end hook must be accurate. 

We have also noticed that some tape measure end hooks are attached at a slight angle by the manufacturer.  This may explain the difference in accuracy between the top edge of the tape measures blade and the bottom edge of the blade.  This is most apparent on tape measures with both standard and metric scales.

Quick Links

Instructions for calibrating tape measures.
If your tape measure is not accurate.
NIST/ISO
Explanation of Equivalents.

Instructions for calibrating tape measures using the Lixer

Checking 6" pull measurement

Checking the 10cm push measurement

• Check the push and pull measurements of your tape measure against the lines lasered or milled into your Lixer tape measure calibration or inspection tool. (These lines are located at 10 cm and at 6"). If your tape measure is accurate to your standards you are done.

If your tape measure is not accurate, you must decide how to correct or identify the problem. The following problems are commonly found.

• If the pull measurement is short, but the push measurement is okay, check to see if the end hook is bent. If it is bent, use the end hook adjustment slot at the end of the Lixer to adjust the end hook. Check with the Lixer again. If needed adjust end hook until it is accurate.
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• Use the slot in the end of your Lixer Tape Measure Calibration tool to adjust the end hook.

• If the end hook is not bent, check the inside of the hook to see if there is a burr left from manufacturing. If there is a burr, use a diamond hone to file it down and check the tape measure with the Lixer again.

• If the push measurement is long and the pull measurement is okay, check for glue on the end of the end hook. Remove glue and recheck calibration.

• If the marks on the tape measure are short on the push and long on the pull measurements, the rivets may be too loose. You can try to adjust this using a drift punch and a hammer to tighten the rivets. You should then recheck calibration.

• Replace tape measures that do not meet your accuracy requirements. The rivets or end hook may be damaged or worn beyond repair.

We also recommend you keep a log indicating when your tape measures were checked. A free .pdf log can be downloaded below by clicking on the image then clicking on "(sample)" or you can contact us at info@lixertools.com to get a .pdf file or an excel file of the log.

Measuring in 1/32 and 1/64 of an inch:

Narrowing the range of accuracy will help to improve the quality of your work. Different jobs require different levels of accuracy. For example: a framer may insist on measurements and cuts that are within 1/8 of an inch. A machinist's customer may require accuracy within thousandths of an inch. We find in our cabinet business, that we often work in 32nd's and 64th's of an inch. The 1/16th inch marks are really the reference point from which we work. We approximate measurements that are in between the 1/16th inch marks by visually dividing the 1/16" increment into thirds. We would then apply the +/- to any measurement in the middle third and use an F or S (F=fat and S=shy) to indicate measurements that are in the other two thirds. We would then reference a close fraction and note a larger or smaller measurement with the following marks.

Examples of +/- = 1/32
21/32 = 5/8+
13/32 =7/16-
Examples of F/S= 1/64
41/64 = 5/8F
27/64 = 7/16S

Trying to measure in 1/32 or 1/64 of an inch without verifying your tape measures accuracy with a Lixer would be pointless.

A trusted, accurate tape measure will be your best friend. It will save you time and money by eliminating common measuring errors. A Lixer tape measure calibrator is essential to assess and maintain a tape measure’s accuracy.

Quick Links

Instructions for calibrating tape measures.
NIST/ISO