On 5 Oct, 10:36, wrote:

What's the best way to re-paint them.

Nitromors

A "paint stripper" wheel on an angle grinder. These look like plastic
pan scourers, cost about 7 quid (Toolstation: Aldi's are crap and
Screwfix haven't had stock in 6 months) Be careful with it though, as
they shred very quickly if you catch them on a steel edge.

Then a wire cup brush (twisted wires, good quality, facemask and apron
rather than goggles) on any bits that are really rusty, such that the
galvanising is compromised. You can go other the galvanising too, so
long as you keep a light touch.

Repeat as necessary.

Then apply primer. As you're already galvanised, then I'd use a zinc-
rich primer (expensive but the best) like Davids 182 (car paint
place). This only needs to go over bare steel and where the
galvanising is pockmarked, you don't need to repaint the whole area if
the galvanising is good.

Then repaint. You can go direct to gloss, as weathered zinc is an
excellent base for paint and doesn't need further priming. You might
use an undercoat first if the surface is physically rough and you want
a top-end job.

If you're painting them black and they don't need to be knock-
resistant, then I'd use a bitumen-based paint. Great for gardens and
wall-toppers, but it's soft against wear and doesn't like being
overpainted.