THE TRADITIONAL WAY
SELECTED SHOP FORMULAE
John T. Kramer
Traditional Wood Conservator
P.O. BOX 8715
Sugar Creek, Missouri 64054
First serial rights, one time use
International Woodworking magazine
VARNISH, SHELLAC & LACQUER
Within the United States (until after the mid-nineteenth
century) there seems to be little historical difference between
varnish, shellac and lacquer. In the orient lacquer was a
specific formulation of highly toxic ingredients which required
many years of ever increasing exposure for the worker to develop
tolerance. Contemporary usage has most often differentiated
varnish as a oil base finish and shellac as a spirit base finish
but, as always, there are exceptions. Old journals often refer to
shellac as varnish and vice-versa.
The method taught in manual arts classes of public schools during the second & third quarters of this century is sure to get a worker in trouble. Two to four coats of shellac sanded between coats as a filler followed by four to six coats of slow drying varnish rubbed out between coats with a variety of materials is slow, laborious, and fraught with problems. It can be elegant.
Oil varnish is made by dissolving the gums and resins chosen
in heated oils (linseed preferred over sweet) turpentine is
generally used as a thinner. It used to be that it was difficult
to make an oil varnish of the quality one could purchase, now
there is no other option. Fire hazard during manufacture is
Volatile Oil Varnish is made by dissolving gums and resins in,
most often, oil of turpentine.
Spirit varnish is made of shellac, gums or resins dissolved in
spirits of wine. They must be quickly applied as they dry very
fast; when sprayed they dry almost instantly, but, extreme care
must be taken with sprayed spirit finishes as fire can occur from
the spraying equipment or from electric and gas appliances
nearby. Good (dust free) ventilation is required when working
with any surface finish.
Before applying any hard finish lay the dust in the area by
dampening floors with water; after cleaning as well as possible.
When using oil finishes protect from dust while drying.
To maximize results of any hard finish rub down each coat when
dry with felt moistened with water and sprinkled with fine pumice
or rottenstone. Use a clean well worn brush and protect from cold
Shellac is made from the exhudations of insects deposited on
trees in the orient, collected and refined. It comes in several
grades ranging from dark orange to clear, it is available ground
and in button forms. Most traditional lacquer outside the orient
was made from the clearest grades of shellac. Lacquer is now made
from modified nitro-cellulose base; and aside from the fire and
health hazards of application; is the most compatible with wood
of any modern finish.
Varnish is made from natural tree gums and resins the best is
made from Amber, Copal and Damar; mastic, elemi, animi, sanderac,
tragacanth, rosin, balsam, benjamine, and others were also used.
Varnish is now made from alkyd resins, a relative newcomer to
finishing hence long term efficacy is still suspect, is entirely
useless when compounded with plastic resins, but, at least of
short term benefit when compounded with a truly conditioning
primer and base. Enamel is nothing more than heavily pigmented
varnish; if made for exterior application the recipe would
include only the hard and tough resins in good proportion to
prevailing climates of the area; and perhaps a little tung oil as
a weather resister (this is the only known traditional use for
tung oil and the only practical one).
Dissolving hard gums and resins requires several days in a
warm place or in direct sunlight, this occasionally turns some of
the oils a slight yellow color; which is oft desirable. Copal
varnish applied to mahogany will produce a good golden-yellow
color after a short time. If natural oils and waxes are first
applied to the mahogony a rich red color will result; the deep
purplish hue so often seen on old work is usually the result of
cochineal and alkanet root used for pigmentation.
Stains, varnishes and shellac are intended to allow the beauty
of the wood to show through; unlike most paints. Some maintenance
is required to preserve the finish. Polishes, oils and
preservatives all add to or detract from the natural chemical
changes which cause "patina." Modern chemicals do not
aid the permanence of appearance.
Old reciepts call for finishes, stains, oils, glues, putties
&c. to be mixed up fresh. This may mean to use immediately
after long periods of preparation up to a month or more.
Modern varnish, shellac and lacquer available at your paint
store bear no relationship (other than name) to the traditional
product and are primarily synthetic petro-chemicals. Even Spar
varnish is today most often a synthetic. A few hard to find
specialty suppliers do offer a few traditional shellacs and
varnishes pre-mixed, though even these most often have synthetic
oil, thinner and spirit bases.
A STANDARD RECIPE FOR SHELLAC OR VARNISH
1 part gum (resin or shellac)
2 parts alcohol
1 part gum
1/2 to 1 part oil
2 parts turpentine
1 part sanderac
2 parts spirits of wine
Mix cold, shake frequently.
4 drams white rosin melted in a glazed vessel
2 oz. white amber finely powdered
Oil of turpentine to proper consistency
Pour in course linen bag and press out varnish.
BLACK VARNISH ca. 1817
4 oz. gum-lac
1 oz. sandarac
1 oz rosin
4 drams ivory black
sufficient spirits of wine
Melt and mix; strain through linen cloth.
1 part copal
1 part sandarac
1 part rosin
5 parts alcohol
Gum copal with equal parts linseed oil, spirits of turpentine,
1 gal. boiled oil
8 oz. umber
3 oz. asphaltum
3 oz. oil of turpentine
1 gal. rectified spirits of wine
6 oz. gum sandarac
3 oz. gum mastic
1 gill turpentine varnish
Put the whole in a sealed tin can and set in a warm place
twelve days shaking frequently intil disoolved. Strain and keep
1 gal. oil of turpentine
5 lbs. pwdered resin
Put in a tin pan on a stove and let boil one-half hour. Ready
for use when cool.
Ordinary traditional oil paint consists of five things;
1. a base of white lead, zinc white or red lead
2. a binder and vehicle generally linseed oil
3. a thinner generally turpentine
4. usually a drier
5. a pigment in addition to the base
The base, itself a pigment, gives body to the paint and
protects the surface treated; the vehicle allows easy application
of the base and provides further protection; the thinner makes
the paint workable; the drier assists oxidation since drying of
oil base paints does not mean evaporation; and the pigment
Enamel is made from fine ground pigment with varnish as the
vehicle. Shellacs and varnishes were often pigmented to provide
translucent colors; when built up in many thin precise layers on
a surface the popular "faux" finishes were achieved to
make plain wood or plaster resemble fancy grained wood or marble.
2 qt. skim milk
8 oz. fresh slaked lime
6 oz. linseed oil
2 oz. white burgundy pitch
3 lbs. spanish white
Lime is to be slaked in water, exposed to air and 1/4 of the
milk mixed in. The pitch is dissolved in the oil and added a
little at a time, then the rest of the milk and finally the
2 qt. skim milk
2 oz. fresh slaked lime
5 lbs. whiting
Put lime in a stoneware vessel and pour a sufficient quantity
of milk on it to make a mixture resembling cream; then add
remainder of milk. Spread crumbled whiting on surface and mix
well. Any color pigment may be then added to suit the fancy.
2 qt. skim milk
6 oz. slaked lime
4 oz. sweet oil
5 oz. spanish white
For outside use add:
2 oz. slaked lime
2 oz. oil
2 oz. white burgundy pitch
No other instructions were included with this reciept of ca. 1815
Skimmed milk 4 lbs., or 1/2 gal.
Lime (newly slaked), 6 oz.
Neatsfoot oil, 1 gill
Color, 1 1/2 lbs.
For outside painting add:
Oil, 2 oz.
Turps, 2 oz.
Slaked Lime, 2 oz.
WHITEWASH ca. 1830
2 oz. alum
18 lbs. lime
2 1/2 lbs. fine ground wheat
2 gal. milk
9 gal. water
1/2 lb. ground hide glue
10 lbs. whitting
2 lbs. salt
For outdoors add:
1 qt. linseed oil, turpentine mix
10 parts whiting
10 parts lime
1 part hide glue
1/8 part alum
water to consistency
Substitute linseed oil for 1/2 water when used outdoors.
MEDIUM CHEAP WHITEWASH
Mix glue size with whiting and paint on.
DIRT CHEAP WHITEWASH
Dissolve quick lime in cold water, stir till well mixed.
3 parts spanish brown
3/4 part whiting
2 parts linseed oil
2 parts turpentine
1 lb. spanish brown
1/2 lb. whiting
1 qt. linseed oil
1 qt. turpentine
Now known as tempera paint made with milk, cheese or hide glue
as the protein bonding agent. Substitute hide glue size and hot
water for the oil, not as good as oil paint.
Mix to the consistency of dough.
Use only enough oil to moisten all of the whitting. Putty can
be pigmented to match the wood, but to a color sliightly lighter
than the natural color. Putty shrinks as its dries and repeated
applications are required for smooth pleasing results.
Hide glue size(thinned with water)
Mix to the right consistency and force into cracks and holes.
If putty needs thickening small amounts of cornstarch, arrowroot,
fine brick powder, or fine ground clay can be added. Clay and
brick dust will pigment the putty. Mix fresh for every job.
Stopping is of three types. The first is a thick mixture of
paint base layed over primer to level the surface of interior
woodwork. The second is hard & used like putty to fill holes
and damage in finished furniture, it is colored to blend with the
wood and finish. The third is soft stopping also called putty.
Hard stopping is made from a mixture of beeswax, shellac,
resin and coloring to match the surface being repaired or
leveled. It is also known as beaumontage and is usually made up
in sticks of various hues and colors ahead of time. It is melted
into the surface with a hot iron or flexible knife. After cooling
it is leveled with a chisel, scraper or glasspaper.
Stopping is commercially available in a wide array of colors
under the name "shellac sticks" and electric hot knives
are sold for application. A flexible pallet knife heated over an
alcohol burner works as well.