Hi all,
have some galvanised steel railings which were badly painted a few
years ago (e.g. looks like they weren't primed and the gloss paint is
now flaking off)

What's the best way to re-paint them.
Should I just go over them with a sander and put Hammerite on them?
Do you need to be careful how 'deep' the sanding is to protect the
surface layer?

TIA PJ