Coat of Many Colors

When faced with bonding a foil strain gage sensor to an anodized aluminum part, should the anodized coating be removed?

To remove or not to remove…that is the question. Fortunately, the answer is pretty clear (pun intended).

It depends on the color.

A clear anodized coat doesn’t interfere with the transmission of strain between the aluminum part and the bonded strain sensor. Clear anodized coatings can stay.

If, however, the aluminum part is tinted with ANY color, then it needs to go! Tinted anodized coats do not adequately transmit the strain from the aluminum part to the strain sensor.

And, if there’s any doubt about removing an anodized coating, then the best practice is to remove the coating. Here are suggestions on techniques to remove the coating.