Veneering
It can be done either by hand (
Hand Veneering ) with warm animal glues, made from
bones, fish, meat or hides (rabbit skin glue is generally considerate the best).
Or in a Press (
Press Veneering ) with either warm or cold glue.
The Press can be either
Platten ( for flat work )
Caul ( for Shaped or
Molded work ) or
Vacuum ( for Any Shape work ).
Hand Veneering
Good quality Veneer maybe had at Rocklers
Handveneering or the laying of
veneer
by hand is normally
done with
warm animal glue.
To this purpose the animal,- or hide-glue is warmed up to 75° Celsius or
165° Fahrenheit but the temperature should not rise above this
as else the protein chains start to breakdown and a distinct loss of
"tackiness" is noted especially when the glue is reheated.
The warming of the glue is done either in a Bain Marie type warming
pan or gluepot this restricts the temperature to 100°
Celsius or 212° Fahrenheit, as when water gets warmer than
this, the energy is used to convert water into steam.
In a
waterless gluepot as opposed to a
normal gluepot
no water is used and they are set so, that the temperature doesn't exceed
75° Celsius or 165° Fahrenheit,
this allows the glue to retain a much greater "tackiness" especially,
if the glue is warmed up more than once.
The warm glue is applied with a brush to the timber, if the timber is very porous
or the veneer is not flat, than it is best to apply a layer of
glue, which is very much thinned down, a day before. This penetrates
the timber and seals it, so that the next application of glue doesn't sink
into the timber thus improving the "tackiness".
The fresher the
veneer
is the easier it is to glue.
In an old veneer the fibers seem to "set" and the cellulose, which keeps
the fibers in place, is less readily softened thus making it harder for
the fibers to shift along one another and allowing the veneer to lay easily
flat upon the timber.
If a veneer is not flat than this can be achieved by wetting the leaves
with water, and pressing them overnight between two flat panels, add a
little Oxalic Acid to this water, for light veneers or those containing
iron, to prevent rust stains (blue-black spots ) from appearing.
Rust spots already in the veneer or wood may often beremoved by washing or
wiping with water in which some oxalic acid is dissolved.
Make sure to treat the whole surface as "edging" may appear where you stopped.
WARNING: Wear a appropriate
facemask when sanding.
The first leave is now moistened and laid flat on top of the glue and
partially warmed with an electric Iron, set on woollen, the warm glue
remelts from this and the glue penetrates the wood and veneer, with a
Veneering Hammer
, this is a bronze hammer with a very wide pein, the
excess glue is squeezed out from between the veneer and the wood. The
airpressure helps the veneer to stick to the wood, but should be kept moist
as drying of the surface makes the top shrink and thus causes the veneer to
curl up.
Now the process may be repeated with the area next to it, until the
whole leaf lays nice and flat.
If the surface needs more than one leaf then the first one is to be
glued slightly over the joint line and the second one is glued with the
veneer protruding the same amount over the joint line
(place where you want the join of the leaves to be ), on top of the first
one.
Then they are the both cut at the same time, after which
the joint is rewarmed and the excess veneer may be removed allowing one to
lay the veneer flat again.
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Veneers
