Wiring: Restoring/Preserving Cannon (Amphenol) Plugs

Cannon plug missing anodizing and with corrosion

Most of the cannon plugs (also referred to as Amphenol plugs) had most of their protective anodizing missing. The internal contacts were good and clean. Rather than spend an incredible amount of time and expense of moving the connectors into new fittings, we opted to preserve the exterior of the plug. We use a two-step process of etching primer followed by a lustreless olive drab marketed by Rapco Parts.

The first step is to use a small stainless steel to remove all corrosion from the outside of the plug. The second step is to apply the etching primer and let it fully dry.

Although the etching primer produces a color that is acceptably close to the original anodizing, primer does not make a good final coat.

The final coat of lusterless olive drab (FS 34086) is very close to the original color of the plug, and having a paint coating on the aluminum housing will extend the service life of the connector and assist in preserving the integrity of the electrical connections.

As a note, we applied the silicone grease to the threads and connections to prevent corrosion of the threads and to provide a slight amount of additional waterproofing to the contacts in the event the cannon plug seal fails.