Here’s a new tip from the TEC team – when determining how to prime your substrate, you can perform the ASTM “Water Drop Test”. Drop some water on your substrate, then time it for 60 seconds. If the water soaks into the substrate completely in 60 seconds, it is absorptive and needs a primer.
If it does not soak into the substrate, it could be non-porous and should be checked for contaminants, sealers or other bond inhibitors before priming.