Zinc based primers are ok, they are conductive and burn off completley (spell checker Ron please [img]/ubbthreads/images/graemlins/grin.gif[/img]) try here
http://www.frost.co.uk/item_Detail.asp?productID=8830
"Zinc Rich Primer.
HIGH ZINC CONTENT
PROVIDING HIGH CORROSION
RESISTANCE AND EXCELLENT
WELD THROUGH PROPERTIES
Directions.
Spray from 25 to 30cm onto the surface to be coated using a series of light coats to build up the thickness required. Allow to dry completely (2-4 hours) before futher painting.
Uses.
GALVANISING SPRAY is for use in production, maintenance and construction industries to provide a protective coating of Zinc over metal surfaces which protects against rust and corrosion. It can be used as a coating on pipes and steel fabrications to reduce corrosion and as an exceptionally good primer coat. It protects welds on both bare metal or previosly galvanised surfaces and as a touch up for marred, hot galvanished surfaces. It protects iron, piping, ducts, water tanks, automotive and marine parts. Test spray area before applying.
Contains 99.9% Pure Zinc."