Post by SimonHas anyone tried this on metal outdoors? I have some iron railings I want
to paint and the Hammerite paint I use keeps lifting with rust every 12
months so I thought I might give this a go. If anyone has tried it what is
the finish like?
Thanks.
The first question is, why is the hammerite is failing? Rust loves a
supply of air, water & metal(!). Assuming you're completely cleaning
down the surface first, then you should prevent rust with hammerite -
providing that the surface is completely covered. This includes
corners and edges, which tend to be weak points which can be tricky to
cover with paint. You may need to put down multiple coats to ensure
complete cover. Also, if you dealing with a tricky surface, try
applying Hammerite No1 Rust Beater before applying the topcoat.
Bitument paint may work, as it provides a good barier to water.
However, you could end up with the same issues as you have with the
hammerite unless you prepare the surface properly and coat the metal
completely. You may also need to apply a zinc-phosphate primer before
application of the bitumen paint. The zinc in the primer works in the
same way as galvanising. It can prevent rust creeping along the
surface, should rust get started in a particular point due to a film
defect.
good luck
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