Strain Gauge Testing on a Desert Island

Strain gauge sensor testing need not be left in the hands of “outside consultants;” it is easily accomplished with some training and a properly equipped lab (or work space). Micro-Measurements frequently trains engineers and technicians on the art and science of gauge installation and is then asked:

“What is the basic set of products needed to set up a lab space in my facility to begin strain gage testing myself rather than hiring outside help?”

Bringing this capability in-house may be accomplished with a few tools, accessories, and instruments, all available from Micro-Measurements.

 

Here is a suggested list of equipment:

 

Strain Gage Installation Checklist, available from Micro-Measurements. We all need checklists to keep track of what needs to be done to get an accurate strain measurement – especially when working with large projects and several team members. Link: https://www.strainblog.com/search/node/checklist

 

The initial step in preparing for any strain gauge installation is the selection of the appropriate gage for the task. It might at first appear that gage selection is a simple exercise, of no great consequence to the stress analyst; but quite the opposite is true. Careful, rational selection of gage characteristics and parameters can be very important in: optimizing the gage performance for specified environmental and operating conditions, obtaining accurate and reliable strain measurements, contributing to the ease of installation, and minimizing the total cost of the gage installation. The installation and operating characteristics of a strain gage are affected by the following parameters, which are selectable in varying degrees:

Strain-sensitive alloy, backing material (carrier), grid resistance, gage pattern, self-temperature compensation number, gage length, options (https://docs.micro-measurements.com/?id=2406).

 

A clean work area or table in a lab, which will vary greatly with the size and shape of test specimens. In our workshops, we do hands-on projects on a desktop with some legal-sized white paper as a blotter and a small glass plate to place gages when removing them from packaging prior to installation.

 

A quality soldering station with accurate temperature control.

 

Degreaser (CSM-3) or isopropyl alcohol (GC-6) for cleaning specimen surfaces to initialize the surface preparation for gage bonding.

 

A set of application tools for handling strain gages, trimming bondable terminals, and preparing lead wires. We recommend the ATS-2 Gage Application Tool Kit containing surgical shears, dental probes, tweezers, and a scalpel: http://docs.micro-measurements.com/?id=6228

 

Surface preparation accessories — conditioner (MCA-2) and neutralizer (MN5A-2), abrasive papers (multiple grits) (SCP-1, SCP-2, SCP-3), cotton tip applicators (CSP-1), and gauze sponges (GSP-1): http://docs.micro-measurements.com/?id=2368. Each item can be obtained separately or packaged in Gage Application Kits based on different adhesive types: http://docs.micro-measurements.com/?id=2397

 

Paper drafting tape (PDT-3)and gage installation tape (PCT-3MD), used for moving a gage into place and masking off gage portions for protection during soldering steps: http://docs.micro-measurements.com/?id=6228

 

Solder, gage adhesive, protective coatings, and rosin solvent. These materials will vary by application and are also included in the Gage Application Kit. https://micro-measurements.com/accessories

 

Appropriate lead wire to connect the strain gage to test instrumentation. Connectors are generally needed at the instrument end of lead wires: http://docs.micro-measurements.com/?id=2383

 

Appropriate signal conditioning amplification or data acquisition instrumentation for receiving and processing data from the strain gage. Micro-Measurements offers a variety of static and dynamic test instruments for each application: https://micro-measurements.com/instruments

 

With this short list of equipment — plus training — you can easily become a strain gage testing master, saving your company the substantial cost of out-sourcing this widely used capability. 

Training Program Schedule: https://micro-measurements.com/training

 

yhernik's picture

Yuval Hernik

StrainBlog Editor in Chief