What Is Shellac?
Lac is a natural substance that is the secretion
of the Lac insect "Laccifer lacca",
is found on certain tress principally in the provinces
of India and Thailand. The lac insect, in the
larval stage, is about 0.5mm in length and sufficiently
mobile to crawl along the branches of the trees
to find fresh succulent twigs. When it has fixed
its position it secretes a protective coating
consisting of a deep-red scale and a yellow to
reddish resin called Lac. Its life cycle is about
6 months with most of the resin being secreted
by the female insects.
The substance is collected from the trees, cleaned
and harvested into bags. The bags of harvested
lac are heated over an open fire and as the lac
melts, the bags are squeezed so that the lac is
forced to the outside surface of the bag. This
process forms sheets of shellac which are then
crushed into flakes for storage and despatch.
The dissolving of shellac flakes in alcohol
is the most widely known use of shellac and forms the
basis of French Polish. No resin has yet been found
which so enhances the natural beauty of the grain of
The technique of applying shellac by rubbing
it onto the furniture with a "rubber" is widely
regarded to have begun in France in the early 1800's,
hence the description French Polish.
Shellac is not only used to produce French
polish, it has had a distinguished history of coating
many different products.
Gramophone Records Paper Coating (e.g.
playing cards) Electrical and Insulation
Hats (stiffening agent) Leather Dressings Adhesives
Confectionery Glaze Pills Glaze Dental Compositions
Making a Polishing Rubber
- Polishing Cotton 100% (lint free)
- Cotton Wadding or Cotton Wool
- French Polish (any type)
- Linseed Oil or Mineral Oil (optional)
- Tear off a 6-9
inch square of cotton wadding and fold
it in half, fold the corners of the rectangle
- Fold the outer corners of the triangle to make a
pad with a smooth sole
- Cut out a 9-12 square inch piece of Polishing Cotton
and diagonally place
the pad of wadding across the centre of the cotton
- Proceed by wrapping,
in turn, all the triangular corners of the cloth over
- Gripping the wrapped pad in one hand, twist
the loose fabric together to make a firm rubber
the twisted ends of the cloth over the pad to fashion
a handgrip, leaving a smooth, crease-free sole.
The polish is applied by opening the pad
and charging the cotton wadding with approximately 4
tablespoons of polish. Ensure that you avoid dipping
the rubber directly into the polish and do not pour
it onto the sole of the pad. Close the rubber and squeeze
out any surplus. Putting pressure onto the rubber allows
the polish to seep through onto the surface. Raw linseed
oil can be smeared onto the sole of the pad so that
the rubber runs smoothly.
The rubber should be recharged when necessary
and the entire process repeated until the grain is filled.
This is what is termed as 'bodying up'.
Using the Polishing Rubber
- Begin by sweeping the rubber smoothly on and off
the surface using parallel strokes
- After a few applications using the parallel method,
coat the surface by alternating circles and figures
of eight. This combination of different strokes will
distribute the French polish evenly
- To rub out any blemishes leave the polish to dry
overnight then lightly sand out any dust particles
that have become embedded in the surface. Using very
fine sandpaper rub along the grain and wipe of the
dust with a clean duster
- Ensure that you work to the edges of the panel and
don't stop moving the rubber or you will leave a mark
- This sequence should be repeated until a satisfactory
build has been achieved, depending on the substrate
this can be in excess of 20 coats
- After the final application, let the piece dry for
several days before proceeding with the spiriting
In most cases this will be the final stage,
which is designed to burnish the polish to a high gloss.
Use thinned down polish to a ratio of three parts 2½lb
polish to 1 part Methylated Spirit.
Charge the rubber with the thinned polish
and using very light pressure, apply the polish in straight
very slightly overlapping strokes along the length of
The stroke must be very straight or you
will produce an arcing pattern to the finish. When all
the pieces have been treated in this way, wait a few
minutes and then repeat the sequence. This time you
should feel a very definite pull as the surface film
is partially dissolved and pulled flat by the rubber.
The resistance to the rubber's movement may tempt you
to speed up; this must be avoided as the surface will
be 'burned'. For the best results slowly pull the rubber
over the surface. If you have any problems wait for
a time before starting again.
Stop when you have achieved a high, even
gloss. There may be some blemishes, such as minor rubber
marks. These will normally disappear as the surface
hardens. If not, repeat the spiriting process after
a few hours.
Brushing French Polish
French Polish can also be brushed onto
the surface and it is recommended that a good quality
polishing mop is used (either an S&R squirrel or
- Load the mop with French polish and apply to the
surface, wait for about 20 minutes, then rub down
with S&R sandpaper
- Repeat the process twice more
- Rubbing with S&R OOOO steelwool apply SUPERWAX
polish to the now hardened polish. Rub fairly gently
along the grain, making sure you cover the whole surface
- Finish with a soft S&R duster by rubbing the
polish to a shine