If
the finish on an old surface is in poor condition, peeling or alligatoring
etc (see painting section ) it will have to be removed completely
before you apply the new finish. How thorough the stripping must
be depends on the new finish you plan to apply. For example, if
you wish to use a clear finish, all traces of the old surface must
be removed. Surfaces for paint or antiquing need only to be smooth
and sound. When working with materials such as paint remover, always
read directions on the can. Work in a well-ventilated place, preferably
out of doors. Spread plenty of newspaper around to catch the sludgy
mix of remover and paint flakes. Wearing protective gloves is recommended.
To remove the old surface, follow these steps:
1.
Remove any decorative hardware from the furniture to prevent damage.
2.
Try removing some of the paint with a scraper or putty knife. Sometimes
this will work but if not, you will have to dissolve the paint with
a suitable paint stripper or burn it off.
3.
If possible work on the surfaces one at a time with the item in
a horizontal position. Flow on a full even coat of the paint stripper
with an old paintbrush. Avoid too much brushing. Let it stand for
about 10 minutes and test with a scraper. If paint requires more
softening, test again at 10-minute intervals until the finish has
softened down to the wood. The old paint will take on a bubbly texture.
4.
When softening is complete, strip off the paint with the blade of
a putty knife or scraper. If the tool has sharp corners, protect
the surface by blunting them.
5.
For rounded or carved surfaces, use coarse steel wool in place of
the scraper to remove the softened paint. Twisted rag can be used
to get in between grooves etc.
6,
If the finish is not removed completely repeat the process again.
Scraping with a very coarse abrasive and sanding may remove some
stubborn patches of paint.
7.
Wipe down the surface with a rag rinsed out in water or detergent
solution and allow to dry for 24 hours then apply new finish.
Burning
off old paint.
Sometimes
if the old paint has built up very thickly or you must strip the
paint from a large area, burning will do the job but it must be
done with great care to avoid charring the surface. Use a multi-purpose
torch with a fan shaped nozzle. Play the flame over the paint until
it blisters then peel off at once with a scraper. Do not keep the
flame steady on any one spot for very long. Your aim is to burn
only the skin of paint, not the surface underneath.
Bleaching.
Another
way to remove the unwanted colour or lighten dark timber is by bleaching,
using a bleaching solution. First sand the surface with No. 1 paper
then No. 0 paper to remove raised grain. Remove any sanding dust.
Apply a heavy coat of bleaching solution with a cotton pad. Sometimes
two different solutions are needed, so follow manufacturer's instructions
regarding the proper sequence and time to apply. Allow drying for
48 hours before applying new finish. When sanding the bleached surface,
only fine grain sandpaper should be used to avoid penetrating the
surface layer of bleached wood.
Note
that if the timber has been stained with a penetrating stain, bleaching
or stripping will not remove the colour, which has to be taken off
by sanding.
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