A field engineer’s guide to choosing the right bonding adhesive for accurate, long-lasting strain measurements
A strain gauge is only as accurate as the bond holding it to the structure. I’ve seen perfectly good gauges produce noisy, drifting, or flat-out wrong data simply because the wrong adhesive was used for the substrate, temperature range, or duration of the test. Adhesive selection rarely gets the attention it deserves, yet it’s one of the few installation decisions that can’t be corrected after the fact once a gauge is bonded, you’re committed to whatever that bond line gives you for the life of the test. In this guide, I’ll compare the three adhesive families I get asked about most — cyanoacrylate, epoxy, and polyimide-based systems across cure time, temperature range, substrate compatibility, and long-term stability.
The adhesive layer isn’t just holding the gauge in place it’s transmitting strain from the structure into the gauge grid. Any flexibility, air gap, or creep in that bond line shows up directly as measurement error, hysteresis, or long-term drift. Getting this right matters just as much as choosing the strain gauge itself, and surface preparation plays an equally important role contamination such as oils, mould-release agents, or residue can undermine even the best adhesive, as we’ve covered in more depth in our post on preparing surfaces before strain gaging.
Cyanoacrylate (CN) adhesives the strain gauge world’s equivalent of ‘super glue’ are the fastest and simplest option for general-purpose bonding, and they’re what most engineers reach for first in a lab or workshop setting.
Typically cures in 1–2 minutes under thumb pressure, with usable bond strength developing within the first five minutes. No mixing, no heat, no clamping fixtures required.
Generally limited to roughly -75°C to +65°C (-100°F to +150°F) continuous service. Above this range the bond softens and creep increases significantly, making CN a poor choice for hot process equipment or exhaust-adjacent testing.
Bonds well to most metals, many plastics, and ceramics. Performs less predictably on porous or highly flexible substrates, and is sensitive to humidity during cure high moisture can cause the bond to become brittle.
Good for short-duration static and dynamic tests, but not recommended for long-term monitoring or fatigue testing measured in months or years, where creep and moisture ingress become a real risk.
Best for: quick lab tests, student and R&D work, single-use prototype testing, and situations where fast turnaround matters more than multi-year durability.
Two-part epoxy systems trade some convenience for significantly better durability, temperature resistance, and mechanical performance making them the default choice for most industrial and field installations.
Ranges widely depending on formulation: room-temperature curing epoxies can take 6–24 hours to fully cure, while heat-accelerated systems can cure in as little as 1–2 hours at elevated temperature. This longer working time also makes epoxy easier to apply cleanly on larger or uneven gauge arrays.
Typically serviceable from around -270°C up to +200°C or higher depending on the specific formulation, with some high-temperature epoxies rated well beyond that for specialised industrial use. This is a major advantage over cyanoacrylate for anything operating outside room-temperature conditions.
Excellent gap-filling properties make epoxy well suited to uneven, curved, or slightly porous surfaces — concrete, composites, timber, and rough-cast metals where a thin cyanoacrylate bond line would struggle to make full contact.
Very good. Properly cured epoxy systems exhibit low creep and strong resistance to moisture and chemical exposure, making them suitable for long-term structural monitoring, fatigue testing, and outdoor or embedded installations.
Best for: industrial and field installations, structural health monitoring, long-duration fatigue testing, and any application with elevated temperature or environmental exposure.
Polyimide and other high-temperature specialty adhesives sit at the top end of thermal performance, purpose-built for the most demanding environments think turbine casings, exhaust systems, and high-temperature process equipment.
Generally requires an extended, staged cure schedule at elevated temperature often several hours at progressively increasing temperatures which demands proper curing equipment and cannot realistically be done as a quick field fix.
Rated for continuous service well above +260°C, with some formulations tolerating short-term exposure beyond +300°C. This is the clear differentiator over both cyanoacrylate and standard epoxy systems.
Performs best on clean metallic substrates that can tolerate the required cure temperature. Not suitable for plastics, timber, or heat-sensitive composites, since the curing process itself can damage the substrate.
Excellent thermal and chemical stability once properly cured, with very low creep even under sustained high-temperature exposure provided the cure schedule was followed precisely, since an under-cured polyimide bond can fail well before its rated temperature limit.
Best for: turbines, exhaust and engine testing, furnaces, and other continuous high-temperature industrial environments where standard epoxy would soften or fail.
As a general rule, work backward from your test duration and operating temperature first, then confirm substrate compatibility:
A Note on Getting It Right the First Time
Adhesive selection interacts with gauge type, surface preparation, wiring, and protective coatings, so it’s rarely a decision made in isolation from the rest of the installation.
Suppliers who work with strain gauges every day rather than selling adhesive as an afterthought can match the adhesive and bonding technique to the specific substrate, temperature, and test duration involved, rather than defaulting to whatever is on the shelf.
This kind of applications support is particularly valuable on complex or safety-critical installations, where a bonding failure months into a test program is far more costly than getting expert advice up front.
At Applied Measurement Australia, we don’t just supply strain gauges and bonding adhesives our team also provides hands-on installation and instrumentation services, so the adhesive, surface preparation, and bonding technique are matched to the actual measurement challenge rather than a generic datasheet recommendation. That expertise carries through to the data acquisition systems that read the gauges once they’re installed, so the whole measurement chain from bond line to logged data is set up to hold up over the life of the test. US-based readers will find comparable depth from established strain gauge and instrumentation suppliers offering combined product and applications support.
If you’re planning an installation and want advice on the right adhesive for your substrate and temperature range, get in touch with our team or see how we’ve approached similar challenges in our post comparing weldable strain gauges vs traditional sensors for harsh mining environments, or browse our blog for more field-engineer guides.
It’s not recommended. Cyanoacrylate is prone to creep and moisture-related degradation over time, making it unsuitable for multi-month or multi-year monitoring. Epoxy or polyimide systems are a better fit for long-term or outdoor use.
Not necessarily many epoxy systems cure fully at room temperature, just over a longer period (often 6–24 hours). Heat-accelerated curing simply speeds up the process and can improve final bond properties, but it isn’t mandatory for every formulation.
Drift is often traced back to adhesive creep, incomplete cure, or surface contamination at the time of bonding rather than the gauge itself. Reviewing the adhesive choice and surface preparation is usually the first troubleshooting step.
Generally no the high-temperature cure schedule required for polyimide adhesives can damage plastics, timber, and many composites. These substrates are better matched to room-temperature or moderately heat-cured epoxy systems.
Contact Applied Measurement: Phone: (03) 98745777 Email: sales@appliedmeasurement.com.au Location: 24a/49 Corporate Blvd, Bayswater VIC 3153 Hours: Monday to Thursday 09:00 – 17:00 Friday 09:00 – 16:00
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