Ames-certified test blocks assure accuracy with your Ames portable hardness tester every time.  Even if you are not using your hardness tester regularly, it still needs to be checked for accuracy.  The accuracy of Ames hardness testers is certified when you use Ames test specimens.  All Ames test specimens are traceable to national standards.

If You are Not Sure Which Test Block to Use for Accuracy Testing, Check out the Video Below:

chart of frequently used scales on Ames tester models
chart of frequently used scales on Ames tester models

You can check your tester’s accuracy by running a test on specimens of certified hardness using the following instructions.

How to check your Ames Hardness Tester’s accuracy in 6 Easy Steps:

Step 1:

Select the penetrator and test block.

Soft materials are usually tested in the Rockwell B Scale, using 1/16″ ball penetrator and 100 Kg Major Load. Hardened steel and hard alloys are tested in the Rockwell C Scale, using a diamond penetrator and a 150 Kg Major Load.

*Do not use the ball penetrator with the steel test block or when testing hard steel. Such a procedure will damage the penetrator and result in invalid tests.

Step 2:

Set up the tester.

Secure the penetrator and the appropriate anvil in the tester. Check the position of the indicator hand. It should rest directly on the dot on the indicator dial. If it doesn’t, adjust the dial by turning the bezel to locate the dot under the pointer.

Step 3:

Apply Minor Load.

Slowly turn the hand wheel to bring the indicator hand to the line marked “SET”. This applies minor pressure load to the penetrator.

Step 4:

Set the Barrel Dial.

Rotate the top of the barrel dial toward you until its pin rests against the upper edge of the Lucite magnifier. The upper line of the barrel’s hardness scales should be exactly aligned beneath the hairline on the magnifier. (NOTE: There is no pin on Model 1-4). These must be aligned visually.)

Step 5.

Apply Major Load.

Turn the hand wheel only until the dial pointer rests on the major pressure load indicated by the chart.

*Be careful to bring the indicator hand exactly to the desired graduation on the dial and no farther. (Once penetration goes beyond the major load, a valid reading can no longer be obtained from that penetration. Go back to Step 2. If reading can no longer be obtained from that penetration. Go back to Step 2. If you did not stop at the major load, then go on to Step 6.)

Step 6.

Take the reading!

Turn the hand wheel back to bring the indicator hand back to “SET” and take the reading on the barrel dial through the Lucite magnifier. Each graduation on the barrel dial indicates two points in the Rockwell scale.

Standard Tester:

With the diamond penetrator, read Column C on the barrel dial (black numbers).

With the ball penetrator, read column B (red numbers).

Superficial Tester:

With either the diamond or ball penetrator, take your reading from the black-numbered N-T column on the barrel dial. (The difference n reading is created by the difference in penetrators: N with diamond, T with 1/16″ ball.)

NOTE: The first two or three tests may be low until the penetrator and anvil have become firmly seated.

Remember, we recommend that you have your Ames hardness tester factory re-calibrated once a year to maintain accuracy and ensure a long life for your instrument.

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