Sanding before painting

[hopeishere]

I'm contemplating painting some doors and skirting boards. How "rough" should it feel after sanding and before painting. I'm going to get a small hand sander but will need to do the fiddly bits by hand. Does it just need to feel a bit rough so just the absolute smoothness taken off it?

Is it gloss you’re painting over? You just need to lightly sand until the sheen is taken off a bit as you’re just proving a key for the paint to adhere to. I usually prime when I’m painting over oil based gloss with acrylic egg shell/gloss.

It's eggshell not gloss paint. Does that make a difference. Will be painting it with eggshell again.

What matters is whether the existing paint is oil or acrylic based and if you’re painting over in oil or acrylic as they can react with each other. You can use a primer (I like Zinsser 123) to avoid a reaction between different paint surfaces but either way, you just need to lightly sand the old paint to key the surface before painting. You could do a small test area to check how it coats.

If the existing paint is acrylic you don't have to sand at all, unless it's chipped. Just clean it well and let it dry. If it's oil based you can use a special primer meant for painting water based over oil. If the paint is badly chipped you will probably have to scrape it, then sand it until it is smooth.