Very hard paint/enamel!

[Alex.]

Hi
A friend of mine is having trouble painting his house guttering, it's a former council house and the gutters are cast iron. They seem to be painted in some kind of super-tough enamel and he's having trouble getting new paint to stick. Sandpaper doesn't make any impression on the old coating, and Hammerite just falls off! Can anyone suggest a way of keying this surface? I suggested a blowlamp, but there might be lead primer under there?
Thanks
Alex.

 

[danelectro]

I think I'd go with replacement plastic guttering, and weigh in the cast iron!!!!
AND you'd be saving on the paint and hard work.

 

[Shedendman]

IMHO,i'd rip it down and replace it with plastic,costly depending on how much there is of it,but TBH it'll be much easier that trying to prep the old stuff,which if i remember had 2 lead based top coats on top of lead primer,so sanding it health wise is not a good idea,not only that you wont get to all the underside,ie close up to the facial board.
You can now get zinc based primer and overcoat that with alkybased oil paints,but its expensive.
Are you double sure its cast iron,done alot of work on old council houses before and have come across gutters and downpipes that were asbestos with a blackish glaze on it or the old bitminous paint

 

[Alex.]

Thanks lads, I'll pass the advice on.