Random question.. but someone might have some knowledge...

Having some cast Iron Bench/Seat ends shot blasted to clean off the years of rust and old crap paint.  Should I have them powder coated whilst they're at the shot blasters, (?60 quid for all 8 items), or just go with good old hammerite.

I'm wondering if powder coating will last as long as hammerite, or which is most durable.

Any experience out there?

Powder coating should last longer than Hammerite but there again you can always touch up the Hammerite, I assume they are cast, so could recommend Galvefroid as a preparation to painting with enamel.

First things first, Hammerite is shit, don't use it on anything. You are far better off with Stokes enamel, but use the right undercoat/primer (probably zinc phosphate loaded red oxide in this case - genuine Galvafroid is very good but it's also very expensive and it may not be compatible with your chosen top coat).

Powder coating is fine so long as it remains intact. Once it get holes in or starts to peel then it looks crap and retains moisture so the corrosion gets worse.

If the bits are truly cast iron then they shouldn't need any paint at all - they will get a patina of rust but they won't rot like steel. Of course, you can paint them to make them any colour you like and some may think this looks smarter, but it won't make a lot of odds to how long they last.

If they are actually steel then they will need to be painted or coated.

Personally, if they are cast then I'd leave them uncoated and if they are steel I'd paint them.

Powder coating is crap. One pinhole and the rust gets a foothold and runs through underneath. You can always repaint something over the old coat. You can't do that with plastic.
Powder coating is only suitable for indoor use.

Sam, if you do want to go down the paint route I've got some proper zinc primer left over from my blacksmithing days, a little goes a long way, especially if you spray it. Otherwise, as Nick suggests, let them develop a surface patina of rust then oil them.

Don't agree with some of the above. I had our cast iron garden furniture powder coated four or five years back and it still looks like new.

Worth every penny.