There are several factors to weigh
when considering polishes and waxes for use on furniture and other wooden objects. One
critical fact is that commercial polishes and cleaning products are proprietary, and the
constituents are rarely fully disclosed. These ingredients may be harmless or harmful to
the furniture finishes and to you, and you would have no way of knowing until after the
damage was done. The ingredients could be, and frequently are, changed without warning or
notification. Through these changes, a product which was previously harmless to furniture
could become less so. In beginning any discussion of cleaning or polishing furniture, it
is important to present a strict warning. Before making any attempt to clean, polish or
wax a surface, make sure that the surface is sound. In other words, make sure that the
varnish or other coating (if there is one) or veneer is stable and not flaking off.
Polishing requires contact with the surface for both application and buffing, which could
knock off portions of an unstable surface
Polishing products are available in three forms;
aerosol (spray), liquid and semi solid. Here is a quick look at their benefits and
drawbacks.
Aerosols
The main attribute of aerosols is
their convenience. However, they may have the serious drawback of damaging the surface and
finish of the object. In general, the best you can hope for with aerosol polishes and
cleaners is that they do no harm to the furniture.
Areosols have been among the worst offenders in
introducing silicone oils and other contaminants onto furniture. In addition, aerosols may
contain a wide variety of solvents which attack varnishes and lacquers. While some of the
"dusting" aerosols appear to be benign when applied to a cloth and not the
surface of the object, the result is not really any better than using a damp, clean
dustcloth.
Liquids
Like aerosols, liquid
polishes are easy to use. There are two primary forms of commercial liquid products for
"furniture care"; emulsion cleaner/polishes and "oil type" polishes.
Emulsion polishes are water-based products whereby waxes, oils, detergents, organic
solvents, and who knows what are suspended in a water solution for ease of application.
These products can be extremely powerful cleaners which leave a desirable sheen on the
surface. However, the visual effect is usually short-lived, diminishing as the liquid
dries. In addition, in the past some emulsions contained abrasives to "aid" the
cleaning and polishing process. The concern over introducing contaminants onto the
furniture with emulsions is similar to aerosols, with the difference that liquids place a
lot more material on the surface. 0il polishes are more troublesome. Much like emulsion
polishes, oil polishes can be a complex blend of ingredients including oils, waxes,
perfumes, colorants, "cleaners", and organic solvents and other materials. They
can render extremely pleasing surfaces and are used frequently as final finishes by
themselves.
However, the potential difficulty from using oils
as polishes or cleaners is enormous. There are two basic types of oils with which we are
concerned; drying oils and non-drying oils. The predicament you face is that regardless of
which oil you have, there are serious problems. Non-drying oils tend to be the more
benign, but there is the issue of an oil remaining liquid on (or in) the surface of any
object. Dust and other airborne contaminants readily stick to wet surfaces, especially
oils. At least these oils (paraffin, mineral, "lemon oil", which is usually
mineral oil with colorants and perfumes added, etc.) don't really undergo chemical
reactions or directly damage the furniture.
Drying oils, such as linseed, tung, or walnut oil,
are a different matter altogether. These materials solidify, or "dry" through a
process of chemical reaction with the air called oxidation. The drying process polymerizes
the oil, making it increasingly intractable with time and more difficult to remove with
cleaners or solvents. This is fine if oil is employed as the finish, but not good if it is
used as a polish. By itself, having a polish which is difficult to remove would be
irritating but not insurmountable. Unforunately, this is not the whole story. As drying
oils age, they tend to become yellow or brown. Also, drying oils are chromogenic (they
become colored) in the presence of acids. In this instance the oil adopts the dark, muddy
brown/black opaque appearance so prevalent in antique furniture. Traditionally,
cleaning/polishing concoctions were comprised of linseed oil, turpentine, beeswax, and
vinegar (acetic acid). This cleaning/polishing method, used widely even in the museum
field until recently, was and is a disaster waiting to happen. The results of this
approach are readily apparent to even the casual observer; a thick incrustation of
chocolate colored goo which is neither hard enough to be durable nor soft enough to wipe
off easily. Thus, due to the polymerization of the oil as it dries and the reaction of the
oil with acetic acid, the furniture is left with an unsightly coating which is very
difficult to remove without damaging the surface of the object.
Semi-Solids
By virtually any measure
semi-solid polishes are the most beneficial to wooden objects. Frequently referred to as
"paste waxes" these products are actually a very concentrated solution of waxes
in an organic solvent or aqueous emulsion (Butcher's, Behlen Blue Diamond, Renaissance,
Johnson's, and many more). Provided the ingredients do not include silicone or other
undesirable contaminants, paste waxes are an excellent material to apply to most finished
surfaces of wooden objects. Because waxes are known to be among the most stable of
materials, and don't encounter the severe deterioration problems inherent in the
previously mentioned polishes, they are the polishing material of choice for furniture
conservators and other caretakers of furniture and wooden objects. That is not to imply
that paste waxes are without their faults, too.
Now for the bad news (followed by more good news).
Unfortunately, wax polishes require the most active contact with the surface of the
furniture, and also need the most physical labor to apply properly. Buffing out a wax
polish can be very hard work, and as you might expect, the better the wax, the harder the
buffing. However, I believe the results and benefits to the furniture are worth the extra
effort.
Fortunately, as the most durable and stable
polishing material, paste wax need to be applied much less often than aerosols or liquids.
Ideally, wax polishing should be conducted infrequently, ranging from perhaps twice a year
for areas of extremely heavy wear (desk tops, chair arms, etc.) to once every three or
four years for table and chair legs, cabinets, etc. The need for new application of wax
can be determined easily. If an surface can no longer be buffed to the sheen appropriate
for a waxed surface, it is safe to assume that the wax has worn off and is no longer
present. In that case, apply another light coat of wax to the affected area in accordance
with the product instructions. If wax is applied too frequently or improperly, there will
be an unnecessary build-up of material, which can be unsightly in itself and also cause
particulates to adhere to the surface of the object. If used correctly, the solvent
content of the new wax will "clean off' any previous wax remaining on the surface,
and will simply integrate the old into the new.
Testing
There is a simple method to
determine whether your polish may adversely effect the object. It will not tell you what
is in the cleaner or polish exactly, but it will indicate how the materials behave. While
this is certainly not a purely scientific approach, you should be able to draw some
conclusions nevertheless. The test is this: apply a generous portion of the polish,
whether aerosol, liquid or semi-solid, to a plate or piece of glass. By
"generous" I mean enough to form a pool or clump on the plate. Leave the plate
out on a counter, windowsill, or other place which is representative of the environment
containing the furniture. Watch what happens and observe what remains (this may take
minutes or months, depending on the material).
For example, if you apply enough aerosol
"dusting agent" to the plate so that there is a pool of liquid from the aerosol,
one of two things is likely to occur. If the material simply evaporates leaving behind no
residue, it is possible that the use of this product may not harm the furniture. But
still, there are a couple of things to consider. If it all evaporates, what are you paying
for? The areosol "dusting agent" provides no function in cleaning or dusting
furniture that cannot be accomplished by judicious use of a damp cloth. What if the
aerosol is comprised of volatile organic solvents which quickly evaporate (a very likely
possibility)? Even in that case, where no residue is left behind, the solvents may damage
the finish on the object, even if the solvents are relatively benign. A mild organic
solvent like mineral spirits (Stoddard's solvent, paint thinner, petroleum benzene) can
remove wax coatings, which were used in past decades and centuries.
But what about the second instance where the
polishing product applied to the plate does not quickly or completely evaporate? Now the
problem is more complicated. What remains could be oils or other contaminants which adhere
dirt and grime to the surface or attack the varnish. Or, the oils could polymerize and
form an intractable coating which may degrade over time or react with other polishing
materials in a deleterious manner. Remember the problems with polishing oils which were
listed above.
While the amount of material put in the
plate may exceed the normal application in polishing an object, the phenomenon observed in
the plate is different only in degree, not in kind. As you watch polishes become gooey,
yellow, rubbery, filthy, or whatever, consider the furniture. What is happening in the
plate is merely an exaggeration of what is happening on the furniture. Over time,
continued use of the product, even if used sparingly, can lead to the same effect becoming
manifest on the furniture.
