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Hardness Tester


The hardness tester

The Instron DynaTestor 10 Ultrasonic hardness tester can be used to measure the hardness of steels when heat-treating them or when deciding what tools should be used to work on them. It come with a selection of diamond-tipped probes and calibration blocks to verify proper operation. It's able to measure hardnesses from around 10HRC up to over 65HRC. It's kept in the upstairs cupboard, in an aluminium flight case. It's kept upstairs rather than with the metalworking tools as it's very sensitive to dust and dirt and needs to be kept clean. This tool was a VERY generous donation from a member and needs to be cared for properly.

Current Status[edit]

Date Status Comment
6th July 2020 Functional Working properly

Normal usage instructions

  1. Plug in the power brick and connect it to the unit (use only the supplied power brick, no substitutions)
    1. Do not turn the tester on yet
  2. Pick a probe and connect it using the supplied cable
    1. The 3N probe uses a very light contact force and doesn't mark materials but it's less accurate
    2. The 98N probe is far more precise but needs much more force and leaves a mark.
  3. Prepare your test sample, the metal needs to be clean of scale and rust and with a flat surface
  4. Turn on the meter and let it initialize. It will display on the screen which probe is connected
    1. NEVER change probes while the meter is turned on
  5. Get one of the test blocks and use it to check calibration on the probe
    1. Pick a test block as close to the expected hardness of your test sample as possible
    2. Place the test block flat on the desk
    3. Hold the probe vertically above it and at 90 degrees to the test surface
    4. Slowly lower it down onto the test block and gently increase pressure to the required test force
      1. Do not test within 3mm of a previous test, you'll get a false result
    5. Meter will beep and display result if successful, or an error message if you need to try again.
      1. This may take several tries, the meter is very touchy about being accurately perpendicular and lowered at just the right speed.
    6. If the result is substantially different (+/- more than 5HRC) from the calibration standard then test again
    7. If still different, then that's the calibration error that you'll need to apply to your test results
  6. Repeat with your test sample
    1. The flat or v-block probe tips can be attached to help guide your probe on large, flat surfaces or on round bar respectively
  7. Clean the probe tip if dirty
  8. Turn off the tester
  9. Put everything back into the flight case
  10. Return to the cupboard

Planned Upgrades[edit]

Parts and upgrades that are planned/Budgeted/Purchased for in the near future

  • None possible, no spares available

Hardness Tester Caretakers[edit]

Knowledgeable Users[edit]

These people are skilled at using the hardness tester and are willing to help others.

Name/Contact Notes
David G


These are the people who look after and repair the hardness tester, they're the ones to contact if there's any problems with it

Name Notes

Recent Changes[edit]

If you make any non-trivial changes to the hardness tester or perform maintenance please note it here, delete records older than 1 yr