Cast Iron Keel

[Gardenshed]

Planning to strip back antifouling and older filler/coatings on my cast iron keel, to clean off some of the rust and then to fill/fair and antifoul
I'm not planning to get a full sand blasting, but will use an angle grinder and abrasive wheel to clean off the existing layers in the worst areas. Questions:
1. what would you coat/treat the exposed cast iron with? ( I understand that it has to be treated very quickly after being stripped)
2. what filler would you recommend for a job like this?

lots of posts and opinions on the inter web and each supplier manufacturer promotes their own solution.
why current thoughts are:
its a cast iron keel so will always have some rust bursting through so be prepared to do some work every time the boat is out of the water
clean back the affected areas, use isopropyl alcohol to dry/clean the surface
paint on VC tax, or a moisture curing epoxy paint, or primocon or deluxe metal shield zinc phosphate primer
not sure which filler to use: west + microballoons or a international/hempel 2-part
then antifoul undercoat and antifouling

and repeat...

[stevepick]

We had a cast iron keel blasted. Once the keel was done we double coated with Primacon the same day it was blasted, then VC tar, then I think we did primacon again as a tie coat and antifoul. In the 6 years we owned the boat after this there were no significant rust bubbles appearing.

Sorry can't help with a filler recommendation.

[Gardenshed]

thanks Steve