Kevin is correct, epoxy primer is waterproof once fully cured. Thus the reason the industry recommends it after sandblasting or striping down to bare metal, sealing the metal from the elements.
Other primers such as high build urethane, polyester or lacquer are porous and must be top coated.


Phil
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1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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