HOW TO DO PAINTING NEW WOODWORK WITH SYNTHETIC ENAMEL PAINT
Woodworks
such as doors and windows can be painted or polished. In this section, we will
examine the painting and in the next section, we will deal with the polishing of
woodworks. Quality painting of new woodwork must be carried out by the following
five preparations:
1. Removal
of knots and preparation of the surface
2. Applying
primer coat
3. Stopping
and filling (filling the hole with putty)
4. Applying
undercoat
5. Applying
topcoats
These steps are described below.
Removal of knots and preparation of the surface. The first function is to
remove the knots and prepare the surface. Trees to be painted, such as doors
and windows, should be well processed and free of discoloured membrane and
adhesive or loose knots. The surface is prepared as follows. It must first be
smoothed with abrasive paper and the projectile fibres removed. Any knots
extending up to about 25 mm (1 inch) beyond the knot area should be applied
thinly around it with business lines or blue subcut pure shellac knot.
If
the area is small and the wood is not highly resinous instead of applying two
coats of knotting, we apply one coat of shellac slightly pigmented with
aluminium powder. The above method of knotting or killing knot is called patent
knotting. (It can also be done by ordinary or size knotting, where we use a
paste of red lead ground in water mixed with strong glue size applied hot on
the knots.
Lime
knotting consists of covering the knot with lime for 24 hours after which it is
treated with ordinary knotting. Another easy method now widely practised is to
fill the knot with Fevicol mixed with fine wood powder scraped from wood.)
Applying primer coat. After knotting, the second operation is to rub down the
surface with sandpaper and apply the wood primer coat or sealer coat to fill
the pores of the wood. This priming coat is generally applied before the woodwork
is placed in position and is to be applied on all portions of the wood.
Stopping and filling.
The third step is stopping and filling. It consists of rubbing down the primed
surface and filling the holes with putty. (For high-class work, we use putty
with one-third white lead and two-thirds ordinary putty). It is then rubbed
down with sandpaper to a smooth surface.
Applying the undercoat and finishing
coats. The fourth operation is
applying the undercoat. After drying of the undercoat, the surface should be
carefully rubbed down with sandpaper and wiped clean before the fifth operation
of applying the finishing coats of paint. Generally, only two coats of paints
(undercoat and finishing coats) are prescribed in ordinary works.
HOW TO DO PAINTING OLD WOODWORK WITH SYNTHETIC ENAMEL PAINT
Repainting of Old WoodWork
If the old paint is cracked
and is in a perished condition, it can be removed by readymade paint removers
available in the market or by traditional mixtures prescribed by PWD
specifications given below. Thick layers are removed by blowlamp or a burning
stove. Then it is painted as described above for new work.
Note: Some of the
traditional prescriptions to remove old paint from painted wood are as follows:
(a) Mix 1 part of soft soap
and 2 parts of potash in boiling water. Add to it 1 part of quick lime and
apply this hot mixture on old paint and leave it for 24 hours. Wash with hot
water to remove the old paint.
(b) Prepare a solution of 1 kg
of sodium hydroxide (caustic soda) in 5 litres of water. Rub this solution with
a rag fixed on a stick (caustic soda attacks human skin). The paint gets
dissolved and can be washed off.
(c) Make a creamy solution
with 2 parts of quicklime and 1 part of washing soda. Apply it on the old paint
and leave for an hour after which the paint can be easily removed.
Must read: Types
of Paint Used in Construction and Its Uses
Must read: Guidelines
of Home Painting
Must read: How
to do whitewashing and colour washing
Must read: How
to Do Painting With Cement Paint
Must read: How
to Do Painting With Dry Distemper
Must read: How
to do painting of plastered walls with plastic emulsion paint
Must read: How to do painting iron and steel with enamel paints?
Must read: How to
do polishing wood which has attractive grains?
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