Experienced strain gage users are aware that certain types of silicones can wreak havoc in strain gage bonding. Silicone grease, aerosol spray containing silicones, hand creams containing silicone, and silicone machining oils all have the potential for contaminating surfaces with a film that is very difficult to remove and will prevent good bond strength with strain gage adhesives. Rather than deal with the difficulty of removing any film a preferred approach is to keep all silicone based materials away from the gage bonding area. Also, any tools used in the gage bonding area should not be “loaned out” to areas that might contain silicones since this material is readily transferred from tools to hands and work surfaces.
Note that these precautions don’t involve silicone rubber used for gage bonding pads as this material does not contain free silicones.
For more Information on Silicone Contamination, please check page 4 of Instruction Bulletin B-129-8.