cast iron keel treatments

[paulwitney]

Any suggestions on treating/preparing a cast iron keel prior to antifouling.
Have tried rust converter and PA 10 and International primer with some success. Also the odd bit of filling those soft mushy rust spots after treatment as above.
Perhaps should just accept the golf ball dimple effect!!!! Boat still goes!

 

[fibz99]

Jotamastic worked for me.

 

[markbloomfield]

I used Primocon on the keels of my Hunter Horizon 30 after wire brushing to remove loose rust. Initially the keels had quite a few rust patches, but the regular application each year seemed to reduce the amount of work after a couple of seasons.

 

[mbay]

I used epoxy paste, the stuff they use on ships rusty hull's where they have pitted.
I cleaned off old paint and rust as best i could, then treated with rust kill followed by a run over the bad bits with the epoxy paste then i painted with primacon.
I know i'll never stop it completely but when I lifted out for the winter there was hardly any rust coming back through.

 

[jleaworthy]

I found nothing worked satisfactorily until I fitted a large button anode to each of my twin cast iron keels ( drilled and tapped a blind hole for a 10mm bolt in each). Corrosion much reduced and antifouling stays in place. Anodes last about 18 months.