Sanding before painting walls
Not much sanding is typically needed unless you have dings, nail pops, or a hole. If you do, you’ll need to do some patching and then sanding prior to painting.
You might want to do a light sand with fine abrasives to remove any small imperfections and to ensure better paint adhesion.
If you do a light sand, choose an abrasive sheet that attaches easily to a hand or pole sander. If you’re spot-sanding dry mud or patching compounds, consider an abrasives sponge that resists loading. And be sure to tack off any sanding dust using a tack cloth.
Trim/moulding/cabinets/furniture
If it’s new, there won’t be much sanding required. You might want to do a light sand with fine abrasives to remove any imperfections.
If you do a light sand, be sure to tack off any sanding dust using a tack cloth.
If it’s been in place a while, you’ll need to sand out any scratches. Fill any holes with wood fillers. Then, you’ll want to sand that to smooth out the surface.(Staining wood
)
Strip off any old stain.Sand down – with the grain – and rough up the entire surface to absorb new stain.
Sand – again, with the grain – between coats of polyurethane.
Always work through a sequence of abrasives grits, from coarse to very fine, skipping no more than one grit between stages.