Prep required before painting new plaster

[shd1970]

Hi all,

I wonder if i could have some guidance on the following please
I had the walls in one of our bedrooms skimmed back in August so obviously, its completely dry now and ready for painting
Just running my hand over the walls, its 99% smooth to the touch but not what i would call polished/shiny
There are a few rough patches mainly in the corners and where the walls meet the ceiling, where it looks like a paint brush was used for some reason

So assuming that the best way to address those rough areas is with some light sanding of the above mentioned, can anyone confirm what grit level i should be using please ?
Is 240 grit too fine ?
Also and probably more importantly, is there any sanding required whatsoever of the majority of the smooth area to form any sort of key, or is it simply get a mist coat applied before a couple of top coats ?

TIA
shd

 

[shd1970]

Hi all,

I wonder if i could have some guidance on the following please
I had the walls in one of our bedrooms skimmed back in August so obviously, its completely dry now and ready for painting
Just running my hand over the walls, its 99% smooth to the touch but not what i would call polished/shiny
There are a few rough patches mainly in the corners and where the walls meet the ceiling, where it looks like a paint brush was used for some reason

So assuming that the best way to address those rough areas is with some light sanding of the above mentioned, can anyone confirm what grit level i should be using please ?
Is 240 grit too fine ?
Also and probably more importantly, is there any sanding required whatsoever of the majority of the smooth area to form any sort of key, or is it simply get a mist coat applied before a couple of top coats ?

TIA
shd

Sorry for the *bump*, but would any kind souls out there be able to advise on the enclosed queries that i have please ?

Thanks in advance