Help! Brush marks in undercoat!

[DIYBeth33]

Hi!

I've been undercoating my stairs (the triangle sides) to hopefully satin finish sometime next week. However, I seem to have terrible brushmarks in the dried undercoat. I paint stripped the original dodgy paint job off and sanded it all down, so it was nice and smooth, before applying 2 coats of undercoat (sanding between coats) and now want to topcoat.

But I find myself sanding it back again to smooth out the brush marks, so will then need to undercoat again as it looks patchy! Aaaggghhhh I feel like I am living Groundhog Day with this, it is beyond frustrating!

Can anyone tell me where I'm going wrong? Any tips? I am just a diy-er, so have no clue where I am going wrong with this!

Any help would be much appreciated! Thanks!

 

[joe-90]

You need to thin the paint by about 5% - 10%, then apply the paint with the grain. Then when you brush is nearly dry, lightly drag it across you paint then leave it alone.

 

[DIYBeth33]

Thanks for the reply! Sorry if I'm being thick, but what would I thin the paint with? Is it ok to thin undercoat?

Sort of wish I'd never started this project! Seems I'm covered in paint/dust all the time and going round in circles! :/

 

[Bosswhite]

If its an oil based undercoat,White Spirit,
If its water based undercoat, Water

 

[DIYBeth33]

Ok! Thanks for the help!

 

[phatboy]

And resist the temptation to go back and retouch a bit you did any more than 3 minutes ago, it will drag the paint off the surface and cause endless amounts of swearing

 

[DIYBeth33]

And resist the temptation to go back and retouch a bit you did any more than 3 minutes ago, it will drag the paint off the surface and cause endless amounts of swearing

Lol! Ok, I will try not to re-brush bit's I've already done, have been following joe's advice of brush it, then leave it alone. Seems to be working!