Painted surfaces are more quickly rubbed down using a wet technique. The cutting power is governed by the material used to manufacture the sandpaper.
Wrap the wet or dry paper around a rubber block, dip in a bucket of water and sand in the normal way. While working, regularly rinse the paper and always keep it wet.
The water acts like a lubricant, enabling the paper to travel over the surface easily. It also holds the paper firmly in contact with the surface.
With a little practice, this type of sanding produces high quality results.
On broad areas, a slight overlapping circular motion can be used.
Narrower areas and mouldings should be sanded lengthways.
Recesses in mouldings can be sanded using a small folded piece of sandpaper, which can be pushed up and down along the groove. Alternatively, for extra control, fold the paper over the end of a scraper.
The surface should be rinsed afterwards using clean water and a sponge. Allow to dry before repainting.
Cut standard size paper widthways in half for cork blocks, and into quarters for rubber blocks.
Always wear a mask to protect against dust. Check that the mask you buy gives protection against the type of dust being produced.