We are going to learn how to select the correct Elmendorf pendulum for fabric tear testing, compare the 16N, 32N, 64N, 128N, and 300N ranges, identify out-of-range results, follow the preliminary testing steps, and recognise unsuitable materials and invalid tears to ensure reliable and repeatable lab measurements.
How Do You Select the Correct Elmendorf Pendulum?
You should select the Elmendorf pendulum range based on the expected tearing force of the test material and the tester’s valid measurement limits. First, perform a preliminary test, then choose the appropriate load capacity, such as 16 N, 32 N, 64 N, 128 N, or 300 N, depending on the tester. If the result exceeds the selected range, move to the next higher capacity; if it is too low, use a suitable lower range.
Elmendorf Pendulum Selection Table
| Ranges of Elmendorf Pendulum | When to consider these ranges | If the result exceeds or is outside the valid range |
| 16 N | Materials expected to require relatively low tearing force | Move to a higher range if the result exceeds the permitted limit |
| 32 N | Materials requiring more capacity than the 16 N range | Move up or down according to the result |
| 64 N | Materials with moderate expected tearing force | Select another range if the result is too high or too low |
| 128 N | Materials requiring greater capacity than the 64 N range | Move to 300 N if supported by the tester and required |
| 300 N | Higher-force materials, using the YG(B)033T | If still out of range, investigate suitability and instrument limitations |
Darong YG(B)033E offers 16 N, 32 N, 64 N and 128 N ranges while the YG(B)033T adds a 300 N range.
How to Select the Range Before Testing
The correct range should be based on the preliminary results, and there is no simple formula, nor is it simply the fabric name or weight.
- First, identify the material and the required test method
- Prepare the representative testing specimens according to the applicable testing standard
- Perform a preliminary test using a suitable range
- Observe whether the results fall within the instrument’s allowed measurement interval
- If the results of the preliminary test are outside that interval, select another range and repeat the test using a suitable testing specimen
- Record the selected range and follow the methods reporting requirements
Do not choose the largest available testing range automatically, and a lower suitable range may provide more useful readings for low-force materials.
Preliminary Test Procedure
- Prepare the test specimen and condition it in the specified test-method atmosphere. For ISO 13937-1, follow the testing conditions as per ISO 139 and prepare the testing specimen as per required fabric directions and obtain the number of valid results required by the testing standard.
Properly Prepared Testing Specimen- Check the specimen’s dimensions and verify its configuration against the method being used. If you are using the Darong YG(B)033E and YG(B)033T, the dimensions of the testing specimen should be 100 X 63 mm.
- Select the initial range and choose the range based on the previous lab data, material knowledge or initial trial and ensure that the Elmendorf pendulum or range setting matches the configuration of the instrument.
- Clamp the specimen and initiate the tear. Secure the specimen correctly, make the prescribed incision, and operate the tester as per the provided manual.
Properly Clamped Testing Specimen- Evaluate the readings and confirm that the test results fall within the valid measurement interval and that the test follows the required path.
- Select the final range and if necessary, change the range and repeat the test with a suitable, unused specimen. Complete the number of required replicates and report the result according to the selected test method.
What Should You Do If the Results Are Too High or Too Low?
Please note that results above the permitted range mean that the configuration of the instrument is not suitable for that measurement; move to the next higher supported range, if available, and repeat the test. For your understanding, a result exceeding the valid interval of the 64 N range may require the 128 N range load. If the 128 N range is not sufficient, use the YG(B)033T, which offers the 300 N range.
If the results are too low, move to a lower range. For example, a specimen tested on the 64 N range can be better evaluated on the 32 N or 16 N range. If the results remain in the lowest suitable range, do not report it as supposed numerical results without qualification.
Can you Simply Change the Range After Testing?
No. Repeat the measurement under the most appropriate configuration using a fresh specimen by following the standard’s requirements, and do not mix readings which are obtained under different configurations without considering the method’s reporting rules.
Which Materials Are Unsuitable for the Elmendorf Method
ISO 13937-1 usually applies to woven fabrics, and it may also apply to certain nonwoven fabrics which are subject to limitations. The method is generally not applicable to knitted fabrics or woven elastic fibres such as spandex, and it is also unsuitable for highly anisotropic or loose fabrics where the tear changes direction during testing. Coated fabrics and other textile material categories may require different methods, which depend on their construction and the applicable testing standards.
Recognition of an Invalid Tear
- Slipping of the testing specimen or improperly clamped
- The incision is not correctly positioned or outside the permitted dimensions
- Tearing does not follow the required path or changes its directions
- The testing specimen is damaged or unrepresentative
- The test results fall outside the instrument’s valid measurement intervals
Conclusion
Selection of the Elmendorf pendulum is a measurement decision, not just a choice between instrument models; use the preliminary results to identify the most suitable range, move upward when the force is too high and move downward when the reading is too low. Always confirm the suitability of the material, specimen preparation and tear validity before reporting test results. For labs testing across a broad range of materials, the YG(B)033E provides capacities up to 128 N, and the YG(B) adds a 300 N range.
Related Resources
How to Identify and Fix Inaccurate Tear Strength Test Results?