Red oxide paint

[XLD]

Is it necessary to scuff the first coat of red oxide down before applying a second coat if it’s a week old (rain stopped me from putting the second coat on after a couple of days) Crown Trade Red Oxide Primer.

[beerbeerbeerbeerbeer]

2 hours ago, XLD said:

Is it necessary to scuff the first coat of red oxide down before applying a second coat if it’s a week old (rain stopped me from putting the second coat on after a couple of days) Crown Trade Red Oxide Primer.

Snap, same here. Painting the top.

Im going to scratch the red down a bit before adding anymore paint. 
Mainly to get rid of the bits that settled in the paint. I was by trees on a windy day.

It won’t do any harm to know you’ve keyed the surface again, it’s easy enough.

It’s surprising how quick you can work over a large surface with a block of wood wrapped in sandpaper

[dmr]

As its a red oxide primer (not a red oxide coloured topcoat 😀) then its fine as it already a matt surface. Its really the gloss paints that need keying. Some/most primers are quite soft so you might go right through in places if you sand too hard.  Some/most primers are not 100% waterproof so as its rained make sure its really dry before you put more coats on.....wait for a sunny day

 

[Tracy D'arth]

Scotpad will abrade the surface without risking going through.

[Stroudwater1]

Snap, but ours is Raddler red topcoat applied 6 years ago, its got horribly oxidised over the last year so kneeling on it gives red knees. Scrubbed x3 and its better though not brilliant. There is no rust other than the odd bubble in a few places. Theres not much non slip surface left relatively either 

 

It doesnt need stripping off really though appreciate its perfection if it were. Would sugar soap then keying thoroughly do, then another topcoat some years after the last, or would an undercoat first be better? 

 

 

[dmr]

I have overcoated raddle without problems, I wash first but do not bother to sand...but do use the rough side of a kitchen washing up sponge for the cleaning.

[Opener]

I've said the same elsewhere recently - be aware that all red oxide paints are not the same in terms of performance.

I ran out of RO half way along the roof a few years ago. Bought and applied a second brand. Within a year patches of the second area started to, what I can only describe as 'drop off', while the original remained secure.

[Tracy D'arth]

How about Bondaprimer instead? It has a resin base and is supposed to be impervious.

[dmr]

1 hour ago, Tracy D'arth said:

How about Bondaprimer instead? It has a resin base and is supposed to be impervious.

 

As the forum knows, I love BondaPrimer and have used it for almost all of my adult life. Like all paints its not quite what it used to be and tends to go lumpy if not used for a while. This can be partly but not totally fixed with a bit of cellulose thinners and a good stir. Otherwise its still good stuff. A few times I've needed to sand off some Bonda and it almost leaves a red stain on the steel so it must be sinking in 😀

[Feeby100]

I steer clear of red oxide as not a great key hold in my opinion