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Menu Buttons |
Provide quick access to helpful features including: |
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Reset |
Clears all data and resets form to initial state. WARNING: all data previously entered will be lost. |
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Save |
Saves the current worksheet. |
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Print |
Prints the report to the default printer. |
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Set Defaults |
Users can set the template to open with a default Manufacturer, Testing Lab, Method and Device to save time on future Reports. |
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Links to the online help file for the Calculator |
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Print Blank Worksheet |
A blank worksheet can be printed by clicking the “Print Blank Worksheet” button. This worksheet can be used by operators to record data during testing. |
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Entering Test Data |
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Enter Sample Information |
Enter sample information required by Section 6 of ANSI/ISEA 105-2011 including Manufacturer, Product Name, Product Type, Test Date, Test Lab (see Set Defaults) as well as optional values for test temperature, humidity, and operator (C2:K6). |
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Select Method and Device |
The Calculator is compatible with both ASTM F 1790-97 (CPPT device) and ASTM F 1790-05 (CPPT, mCPPT, or TDM-100 devices). The proper method and device can be selected using the drop-down boxes (Q5:6). The Calculator automatically changes the calibration load and reference distance to the correct values for the selected methods. |
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Enter Calibration Distance Data |
A calibration cut should be performed before and after each sample test using the indicated load (D13, D29). The blade sharpness correction factor is then calculated for the device being used. |
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Enter Sample Load and Distance Data |
The load and distance values for the 15 sample cuts should be entered in grams-force (gf) and millimeters (mm) respectively (C14:D28). Distance values below 5 mm and above 50 mm are not recommended by the ASTM method but can be entered into the Calculator. The Normalized distance value for each data point is calculated automatically based on the blade sharpness correction factor determined by the calibration cuts. |
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Selecting No Cuts |
If a sample fails to cut within 50 mm of blade travel, that data point is to be excluded according to the ASTM method (cr. ASTM Method). However, the Calculator is capable of analyzing these “No Cuts” using censored regression (see Analyzing No Cuts) to reach a better estimate for the Rating Force of the sample. To include a “No Cut” in the analysis, simply click the cell to the right of the normalized cut through distance (I14:28) for that cut. When clicked, the recorded distance will be changed to 50 mm and the value will be treated as a censored value in the regression. Some devices are capable of the recording distances above 50 mm, in which case the maximum recorded cut through distance can be used. |
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Including Multiple Samples |
The Calculator can be used to test up to three samples of the same product and reporting an average Rating Force and corresponding Performance Level. To include Sample 2 or 3 in the average, simply check the box labeled “Include” (L8, S8) next to the respective Sample name. |
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Interpreting Results |
The Calculator uses inverse regression (see Inverse Regression Procedure) to calculate the Rating Force estimate for each sample test. In addition to the Rating Force and R-Squared results, the Calculator also shows the 95% Confidence Interval, Standard Deviation, and Correction Factor for the estimate. The additional results are useful for
gauging product or test consistency but are not factored into the Performance Level of the product, which is based only on the average of the three sample rating forces. |
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Optional Sample Properties |
Additional sample properties such as thickness and basis weight (E37,E38) can be included on the Report. Two blank cells are provided for other properties and custom calculations (E39, E40). |
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Recommended Testing Procedures |
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Three representative samples of the product or lot should be tested in succession.
A calibration cut should be performed before and after each sample test. If the samples are tested in succession, the calibration cut after the previous sample can be used as the first calibration distance for the next sample.
3 equally spaced loads (for example, 100,200,300 and not 100,150,300) should be chosen that will likely produce cut through distances in the 3 ranges specified by the ASTM methods (cr. Section 10.4.12): (1) 5-20 mm, (2) 20-33 mm, and (3) 33-50 mm.
5 cuts at each load should be randomly performed on each sample for a total of 15 cuts per sample.
Distances less than 5 mm should be included in the analysis, and values greater than 50 mm should be indicated as No Cuts. It is not necessary for each distance range to contain exactly 5 cuts at the same load as long as the three loads are equally spaced, produce no more than 3 No Cuts, and are randomly assigned to the testing sequence. If a particular load produces more than 3 No Cuts it is recommended to restart the test with a higher load. |
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