In many of our product data sheets, you may notice this or a similar statement under the Compatible Surfaces or Substrates section:

“May be applied over properly prepared and treated bare metal”.   But what does this mean?

This means that your bare metal substrate must be properly sanded and treated with an appropriate direct-to-metal product such as an SX metal treatment, etch primer, or epoxy primer prior to applying anything else. These coatings insure adhesion for subsequent layers over the bare metal as well as provide additional corrosion protection.

This step is especially important when using urethane primers or sealers. Their chemistry typically does not provide adhesion to bare metal – they must only be used over treated bare metal to insure optimum adhesion. So if you happen to sand through to metal, apply a bit of etch primer to insure it sticks!