PAINTING TIPS: USING ABRASIVES

PAINTING : USING ABRASIVES

During the process of preparing surfaces for painting it is often necessary to use abrasives in order to sand down rough edges. There are many types of abrasive on the market, each designed to use on a particular surface or in a specific situation. See the chart below for a breakdown of abrasives you might need when doing DIY decoration.

TYPES OF ABRASIVES : Glass paper/sandpaper

DESCRIPTION : Fine particles of glass or sand held on pliable thick card backing. Supplied in sheets of fine to course grades.

USES : General-purpose abrasive used when preparing surfaces, or for sanding down between coats of paint.

TYPES OF ABRASIVES :  Aluminium oxide grit abrasive paper

DESCRIPTION :  A very robust and hard-wearing material supplied in rolls or pieces cut from a roll.

USES :  General-purpose abrasive, as above.

TYPES OF ABRASIVES :  Wet-and-dry abrasive

DESCRIPTION :  A strong flexible black sheet material that can be used as a dry abrasive or used with water.

USES :  Very useful for 'flatting down’ between coats of paint. Also useful where a surface needs to be cleaned as well as sanded.

TYPES OF ABRASIVES :  Soda block

DESCRIPTION :  Known as caustic soda blocks because of their alkaline nature. Used with water on the surface to be prepared (not dipped in water as it tends to dissolve).
Note: Thorough rinsing of the flatted surface is necessary.

USES :  Helpful when a painted surface needs 'taking down’ - when a defective paint layer removed.
Also useful for helping remove stubborn grease.

TYPES OF ABRASIVES :  Steel wool

DESCRIPTION :  Supplied in bundles, which vary in coarseness. Can be used dry or wet.

USES :  Useful when rubbing down intricate surfaces such as stair spindles. Can be used in conjunction with paint or varnish remover.
Gloves are recommended.

TYPES OF ABRASIVES :  Plastic scouring pads

DESCRIPTION :  Small pads of plastic fibre. Can be used wet or dry.

USES :  As above.

TYPES OF ABRASIVES :  Wire brush

DESCRIPTION :  Wire filaments set into a wooden handle; vary in length and width.

USES :  Used mainly on metal surfaces for cleaning off rust. Safety note: Always wear protective goggles or safety glasses. Can also be used to 'scuff' (remove the top surface of) washable wallpaper before stripping.

TYPES OF ABRASIVES :   Liquid abrasive

DESCRIPTION :   A solution of abrasive particles, which is applied to painted surfaces, rubbed with a wet cloth, then rinsed off

USES :   Useful for 'flatting down' gloss paint.


TOOLS TO USE WITH ABRASIVES
In addition to sanding by hand, there are a number of electrical mechanical tools to help make the job easier.
Safety note: In addition to wearing a dust mask, eyes should be protected by safety glasses or goggles, especially when using electric sanders.

Electric belt sander Takes a continuous length of abrasive. Useful when large areas of surface need to be heavily sanded and smoothed off.

Disc sander (electric) Uses various grades of sanding disc. Useful for general preparation of surfaces. Note: Tends to leave concentric sanding rings on the surface, if care is not taken.

Finishing sander (electric) Uses small sheets of various grades of abrasive that fit onto an oscillating pad. Used for light sanding jobs.

Flap wheel Small flaps or strips of abrasive held onto a central spindle This fits into a ‘chuck’ of an electric drill. Useful for sanding contoured areas.

Triangular (detail) sander Uses special triangular-shaped sections of abrasive (fine grade to course). Handy for sanding small areas, particularly getting in to the edges of surfaces such as window sections.

Note: It is possible to get multi-purpose all-in-one sanders.