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Colouring with water based colour and
brushes/sponges
The most important thing to remember when using any sort
of colour or stain is that it will not hide a poor finish. Any
torn grain will show up as spotty or blotchy darker areas - so it
is worth while spending a little more time sanding.
The technique is fairly straightforward -
Sand the
piece to a smooth (but not highly polished) finish. I sand to
about 600/800 grit (depending on the timber). If you use much
finer grit, you tend to seal the surface and the paint will not
spread smoothly - but on a thin piece it reduces the chance of
paint 'bleeding' through to the other side.
Spray the sanded surface with water (or brush /wipe it on) and
let it dry. The piece will feel 'furry' because the water will
have raised the grain.
Sand it back again.
Apply the water colour. This time the grain will not raise and
spoil the work as you apply the 'water'. It can be applied with a
soft brush or a sponge pad for large areas and colours can be
blended whilst still wet. It can also be painted with fine
brushes so that grain effects can be enhanced (See the Jupiter
platter).

Leave the colour to dry.
Rub back with Webrax.
Apply a coat of sanding sealer (diluted 50/50 with white spirit).
If it is a solid area of colour, this can be applied with a brush
or paper towel - but if areas are being left without colour,
using several light coats of a spray on product can prevent the
colour from running.
I usually use a wax finish over the sanding
sealer.
Enhancing Grain with
Wax
In plain wood like most Ash, the grain can be enhanced
by using a coloured wax.
The technique is very straight forward. I usually do it while the
piece is on the lathe as it cuts down the work needed.
Finish
the piece with sanding sealer.
Rub the coloured wax into the grain. I usually use my fingers to
push the wax into the grain - but if you don't like wax under
your nails, wear a rubber glove!
Leave the wax to dry for at least an hour.
Apply paste wax to the surface and spin the piece on the lathe,
rubbing the softened, coloured wax off the surface of the piece.
If it all does not come off the first time, apply more paste wax
and repeat until the wax is only visible in the grain and the
piece has a good lustre.
Once again,
this technique will show up areas of raised end grain and you
should try to get the best finish you can before waxing. Coloured
wax is available in gold, copper and silver as well as black and
white (liming) and a variety of browns.
To enhance the effect, you can try brushing the grain with a wire
brush before sanding.
Making your own coloured
wax
A greater variety of colours can be obtained if you mix
a pigment into some wax. I have tried it with liming wax as the
base. You can also mix the colour into clear wax. The liming wax
gives soft tints – the clear wax does not change the colour
of the powder. Don’t mix up too much as it dries out quite
quickly.
The pigment needs to be something that does not dissolve and
stays in suspension in the wax. I have found that ‘Earth
pigments’ (available in good art and craft shops) work as
do the fine powders used to gild picture frames, clocks etc in
the past ( a technique known as ‘Ormolu’). Product
details of things that I use are in the products list. Please
note the disclaimer at the top of the list.
Air Brush colouring
The first tip is to invest in the best airbrush you can
afford. It is possible to get cheap air-brushes – but they
can be very frustrating to use!!!!! You get what you pay for in
this life!
My second tip is to get an air-brush with a paint reservoir on
the top rather than one you have to screw a jar underneath. They
take less colour at a time, but they allow a huge amount of
flexibility and you can mix new colours in the reservoir as you
progress through the project. For delicate small jobs (which are
usually what you want on a piece of woodturning) you can use just
a few drops of paint at a time – so the reservoir makes the
air-brush more economical as well.
My third tip is to invest in a purpose built stand/ cleaning kit
for the air-brush. These sturdy containers allow you to spray
excess paint from the reservoir and to pass water or cleaning
medium through it between colours as the tip of the air-brush is
contained within the lid by a rubber gasket. There is a filter on
the lid to trap anything as the air escapes. If you spray a short
burst of air-brush cleaner (something like liquid xylene) into
the container at the start of the job, then the airbrush will not
clog and need stripping down and cleaning if you have to leave it
for a few hours. I have actually left mine for days on a couple
of occasions.
I have tried a number of water based air-brush paints but have
found the best to be a make called ‘Golden’. These
are sold in sets of 12 opaque and 12 transparent colours in small
plastic bottles with ‘dropper’ lids. You need so
little that the cost of the set is very reasonable. The ones I
bought over 5 years ago are still liquid and the right
consistency. It is possible to get larger quantities of the
colours you use most and use the larger pots to fill up the small
ones as you need to. They mix well in the reservoir and so-far
have resisted fading (5 years).
I find I get best results on work that has been sanded and then
coated with a thin coat of sanding sealer – as this stops
the colour from running through the grain by capillary action. I
use a spray finish to seal the colour such as sanding sealer or
one of the lacquer/ melamine finishes.
If you want a very high shine and sand to 1500 grit or more, the
paint will not spread evenly on the surface without sanding
sealer. Putting a few drops of air-brush medium in the paint
helps it to spread without forming droplets. The important thing
to remember is to spray very little at a time and let it dry
before adding another coat.
Always start the air-brush off the work (it will normally
splatter for a moment) and bring it onto the work when the colour
mist is even.
Ebonising
Ebonising (painting it or staining it black) can be a very
effective technique to show up the form of a piece or to add
drama and impact.
Some wood can be very plain and ebonising can add value! Some
reasonably plain wood is enhanced if it is ‘framed’
by an ebonised section – especially, in my mind, if it has
a super, deep, glossy finish – but that is all about
personal taste!
Ebonising spray is easy to use and can be done on smooth or
textured surfaces (but it doesn’t hide a bad surface!!!!).
It is a good idea to protect your lathe and chuck if you spray a
piece while it is turning.
Ebonising is also a splendid background for pushing coloured wax
into the grain (see earlier) and for using interference or
iridescent paints (to follow).
Adding Sparkle
Look out for cross-over from other crafts. Rubber stamps
can be used with glue instead of ink and then fine glitter powder
can be sprinkled onto the glue and the surplus dusted off when it
is dry. Even randomly drawn glue trails over a piece can be most
effective. It helps the longevity of the piece to finish with a
spray lacquer /melamine finish to fix the glitter so it does not
come off with handling.
You can get spray lacquer with tiny pieces of glitter in it. This
is very effective, especially on a textured surface. It comes in
gold, silver and copper (see list).
Adding Iridescence
There are paints on the market called
‘interference paints’ that completely disguise a
blackened surface. This is useful if your piercing tool
carbonises the inside of the cut and you do not want the pierced
pattern to stand out and don’t fancy hours of details,
delicate sanding. A brush ‘lightly’ charged with
interference paint, gently run around the carbonised inside edges
leaves enough paint to disguise the black and leave an iridescent
shimmer in its place.
A company called ‘Jo Sonja’ make a good set of
iridescent colours that you use anywhere on a piece to give a
stunning finish. They work best against a dark background. They
look white as you paint them but dry to their iridescent colour.
(My favourite is the purple on an ebonised
surface).
Crackle effects
I once went to a lecture about paint drying and, I kid
you not, it was fascinating. A huge amount of chemistry is
involved in getting paint to do its job and companies spend huge
amounts researching new products.
One kind of paint that can be used to give very interesting
effects is crackle paint. As it dries, it shrinks and cracks,
giving it an ‘aged’ and very interesting appearance.
It seems that the thicker you use the product, the bigger the
‘crackle’ Less than 1mm thick gives a fine crackle
and 2mm gives big crackles – but they seem less well fixed
to the surface and need a few coats of lacquer to protect them
from flaking when handled. It is a beautiful and attractive
textured surface though and requires very little skill or effort
– always a bonus!
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