Accurate specimen dimensions are critical for getting accurate stress and modulus results, but the typical specimen measurement process can be time consuming and prone to data entry errors.
The basic set up for this process usually involves the operator using some sort of handheld caliper or digital micrometer to take the dimensional measurements of each specimen and then manually inputting that data into the testing software. Depending on the testing standard, you may be required to take multiple readings of each dimension. For example, you might need to measure at three different points on the specimen’s width and thickness.
No matter how good your data entry skills are, everyone is prone to an error here or there – so using this method carries with it a certain level of risk that bad data could enter your data set and affect your test results.
The good news is that if you use Bluehill® Universal, Bluehill 3, Bluehill 2, Partner™, Merlin™, or Series IX™ there is a very simple solution that can speed up this process and remove the risk of data entry errors.
All you would need to do is plug a compatible digital micrometer or caliper that has the automatic data entry interface into your Instron testing system. The testing software will recognize this device and allow you to use it when you need to record your specimen dimensions. With the micrometer connected, you simply measure your specimen dimensions like you normally would and then click a button on the micrometer to send the digital measurement directly to the software – allowing you to skip the manual data entry step entirely. If two devices are required – for instance, one for the width measurement and the other for thickness – an interface box can be included to connect both for simultaneously usage.
These micrometers can also be configured with a footswitch, allowing you to tap the footswitch to the enter the specimen dimension into the software.
In Bluehill you can set the required number of readings. In the example shown above, you can see we have set it to require three readings for both the width and thickness. In addition, the reported results of the readings are configurable to report the average, minimum, maximum, or median.