Do stripped back railings need both undercoat and overcoat?

[boilerfrustration]

I've stripped back some railings right back to the dark metal. I want to paint them black using an oil based paint. But do I need to paint on an undercoat first or is okay to put the finishing coat straight on?

 

[RMS]

If you've stripped them right back as you say then an under coat will be required.

 

[misterhelpful]

I would generally use Zinc Phosphate primer rather than an undercoat for most stripped back railings, followed by a good quality one coat gloss system.

 

[boilerfrustration]

Does the need to apply a primer apply to both indoor and outdoor metal railings?

 

[elrobbo82]

i would always recommend priming metal work. for railings i tend to use red oxide primer. this gives good adhesion properties, protects against corrosion and gives a good surface to apply undercoat. make sure you get rid of all rust with a wire brush before priming.

depends on what finish your after though. if glossing i would prime, undercoat and gloss.
another option is prime with red oxide and then apply black hammerite straight over the top.

 

[TheDec]

Does the need to apply a primer apply to both indoor and outdoor metal railings?

What exactly do you mean when you say indoor railings????

Dec

 

[boilerfrustration]

metal balustrades

 

[misterhelpful]

metal balustrades

Ah, I just presumed you meant exterior railings.
If they are dark then it is probably likely that they are some form of ferrous metal and therefore I would still use some kind of metal primer. It doesn't have to be the zinc phosphate or red oxide as a universal metal primer will be fine indoors.
You may well 'get away' with just the oil based finish coat but, personally, I would use a primer to be sure of longevity.