Missing some steps when bonding a strain gage ?

The importance of attention to detail, and precise adherence to instructions, cannot be overstressed in surface preparation for strain gage bonding.
Strain gages can be satisfactorily bonded to almost any solid material if the material surface is properly prepared.
While a properly prepared surface can be achieved in more than one way, the specific procedures and techniques from Micro-Measurements offer a number of advantages.
To begin with, they constitute a carefully developed and thoroughly proven system; and, when the instructions aren’t being followed precisely (along with those for gage and adhesive handling), the consistent result will be as shown in the video.
Fundamental to the Micro-Measurements system of surface preparation is an understanding of cleanliness and contamination. All open surfaces not thoroughly and freshly cleaned must be
considered contaminated, and require cleaning immediately prior to gage bonding. Similarly, it is imperative that the materials used in the surface preparation be fresh, clean,
and uncontaminated. It is worth noting that strain gages as received from Micro-Measurements are chemically clean, and specially treated on the underside to promote adhesion. Simply touching the gages with the fingers
(which are always contaminated) can be detrimental to bond quality. The Micro-Measurements system of surface preparation includes five basic operations. These are, in the usual order of execution:
1. Solvent degreasing
2. Abrading (dry and wet)
3. Application of gage layout lines
4. Conditioning
5. Neutralizing

[miguelbravo]

El no haber usado los materiales adecuados de preparación de superficie y pegado al momento de instalar bandas extensométricas, o no haber considerado las condiciones ambientales durante el ensayo o la duración del mismo, puede ocasionar el rápido deterioro de la instalación y por tanto el fallo de la misma.
En Micro-Measurements ofrecemos todos los materiales necesarios para instalaciones duraderas, en función de las diferentes aplicaciones que se puedan presentar. De igual manera desde nuestra oficina de España (Vishay Precision España, s.l.), ofrecemos todo el soporte que precise para asegurar el éxito de sus ensayos extensométricos.
Por favor no dude en contactarnos y estaremos encantados de poderle ser de ayuda.