A coat of wood primer seals the surface and acts as a “key” for the subsequent coats of paint. e If the abrasive paper clogs, clear it by drawing the uncoated side to and fro over the edge of a table or your work bench. o Fill any cracks or dents in the wood with cellulose filler if you intend to paint it. Use matching wood stopper prior to varnishing. o When the primer is dry, apply a layer of undercoat. Wait until this is dry and finish with a top coat. Woodwork Timber doors and windows, and their frames, are subject to pene- trating or rising damp – inside as well as outside. If you find areas of paintwork where there are hollows in the wood surface, or paint has flaked away, push into it with a sharp knife blade. If it sinks in with little resistance, the wood is rotten and there is no point redecorating until you have repaired it. The first step is to lift out all the rotten material using a narrow chisel, cutting back to sound wood.
If the gap left is large, cut and shape a new piece to fill. However, before you fit this, make sure the area is dry. If it feels damp, speed up the drying process with the aid of a hot air gun or blowlamp. Hardening and filling When the area is dry, apply a proprietary wood hardener to all the wood in the area of the repair. Be generous – allow it to soak right into the wood fibres and dab it in with a brush. For extra protection you can drill a number of holes, about 4mm C …• in) in diameter, in the nearby wood and tip hardener into them. It will take about six hours to set, and will strengthen any soft fibres and prevent the ingress of more damp. Next, use a two-part wood repair paste to fill the hole.
Check the instructions for the ratio of catalyst in one tube to repair paste in the other. Mix them together well, until they take on a uniform colour, then fill the hole using a small trowel or filling knife. Leave the filler just proud of the surface and, when it is hard fin about 20 minutes at normal room temperature), smooth it flush with glass- paper. Always work in the direction of the grain of the wood to avoid ugly surface scratches. Drying time of filler is about halved if you are working outdoors in hot weather. If you plan to paint the wood afterwards, then any two-part woodfiller will do the job.
If, however, you intend to stain it and finish off with a seal or varnish, then make sure you choose a filler that will take stain. Some fillers will not, and you will end up with ugly blotches where the stain has been repelled. o To protect wood around doors and windows, drill holes in the timber wide enough for wood-preserving tablets. If the wood subsequently becomes damp, the tablets release a fungicide that inhibits rot. e Fill the holes with an exterior-grade wood filler. Push the filler well into the holes, and clean up with a scraper or filling knife. Leave the filler just proud of the surface and sand it flush once it has hardened.